Why are linear PSUs so expensive?

[Stubies]

I wonder about this. Most are 100 GBP and up

The transformer and other parts are not so expensive, are they?

Could someone help me with this?

For example, here is one for 24V that i could put into a box. Would this be ok for a Phono Stage? Or just dont?

http://www.ebay.co.uk/itm/310724666920

this seems like such a nubie question...

[Rare Bird]

I never follow trends.

[walpurgis]

never follow trends.

Yup, I agree!

Never listen to hype and try not to be guided by other people's opinions. Trust your ears!

[The Grand Wazoo]

......and try not to be guided by other people's opinions.

Is that your opinion Geoff?
If so, then what the hell are we supposed to do?!

[Oldpinkman]

Depends on the kit you use it with and whether that further regulates or smooths the supply. Cheap ones often go pop. Most audio would ideally like to see ruler flat dc but I have used a £5 supply for my tt and a £25 unit for ky headphone amp. I tried batteries instead, and apart from frying the input smoothing cap on the amp there was no effect on sound (but when I have finished the mods I will repeat the experiment -with a higher rated capacitor! )

[MartinT]

Remember that any manufactured item is likely to have an uplift from cost of 3 times in order to set a retail price. That's just market forces at work and the need for the manufacturer and retailer to feed their children.

Linear power supplies are also more expensive than SMPS because they use larger transformers with more iron and are generally more bulky. Whether the regulation is better is entirely down to the circuit topology and component quality. Remember that you can get very good SMPS and very poor linear PSUs!

[Oldpinkman]

Remember that any manufactured item is likely to have an uplift from cost of 3 times in order to set a retail price. That's just market forces at work and the need for the manufacturer and retailer to feed their children.

Linear power supplies are also more expensive than SMPS because they use larger transformers with more iron and are generally more bulky. Whether the regulation is better is entirely down to the circuit topology and component quality. Remember that you can get very good SMPS and very poor linear PSUs!

Why is there no "like" button on this forum?

If you could just remind Steadman of that. I realised in the bath why his 100% mark-up at his shop was equivalent - vis no further retail cost. 100% markup at factory gate is about right, but then a retailer is going to add a further 40% to that (which is why the web is destroying high street shops and their service). So production cost ends up about 1/3 final retail as a rule of thumb (as an accountant I should be advocating more sophisticated demand curve variable incremental pricing models - but bollocks to that - everyone just uses 1/3 1/3 1/3 (production, manufacturer overheads, retail margin). If you export there is also about 20% uplift from factory gate for duty, shipping, and importer margin, to which the importers dealers then add 40% (plus local sales tax).

But it's why, if you have the skills and knowledge, DIY will always represent unbeatable value. To expect retail from a reputable supplier to be production cost is seriously naieve and frustratingly common. :)

[Ali Tait]

Add it up for yourself - look at all the parts that go into making one - transformer, smoothing caps, bridge rectifier, regulator, cable to wire it up with, solder, soldering iron, IEC inlet, switch, feet, not to mention an enclosure to put it in, and the labour involved building it. You will be surprised how quickly it all adds up.

To give you an idea, not a power supply I know, but I asked Nick about building me a direct coupled GM70 amp to drive my electrostatic speakers - the transformers alone cost 2K.

[StanleyB]

It is possible to buy a decent enough linear power supply like say one of the Maplin CB radio versions. The cheapest one costs less than £30. You can then stick something like a sBooster on it to reduce the noise even more. I have bought one and tested it extensively. It is a real bargain buy and compares well in terms of measured noise etc against the Mark Grant version. If they were not so heavy I might even have bought a couple and done some upgrades on them and sold them afterwards as a modified unit at a profit.

[Gazjam]

+1 on the Maplins one, especially the 7A version

[anthonyTD]

There are of course more advanced linear regulator supplies that use no "off the shelf regulators" which are much more expensive, but far superior in design as far as noise, and regulation, these will inevitably cost more to build and produce.
A...

[MartinT]

Indeed, and good examples of excellent linear PSU designs are the products of Paul Hynes and Nick Lurcher.

[MCRU]

I don't think £100 is expensive who agrees?

Sound quality is surely what matters most, price is 2nd within reason?

Since I partnered with Nick we have sold 100's if not 1000's of linear power supply's and the least expensive is £195, out of the many 100's sold 3 have sent them back.

[StanleyB]

It's all relative really. I happen to prefer using a battery pack with a DAC for instance, where it is technically possible to do so. To get the equivalent low noise performance from a power supply will set you back quite a bit of money.

[Arkless Electronics]

The price of transformers has gone through the roof just lately due to soaring world metal prices... China is forcing prices up. They have approx. doubled in price in the last two years. Although switch mode PSU's are vastly more complicated they use much less metal and so provided they are being mass produced can be cheap.

Some PSU's are indeed over priced of course (ones from the Salisbury area come to mind!).

It is by and large a myth that "special", "exotic" or just huge external PSU's have a large beneficial effect. Virtually no solid state pre amp or phono stage really needs anything more than a wall wart supply (there's another myth exploded :eek:) as the whole power supply quality thing, whilst very real and very important, is entirely dependent on the quality of the internal regulation and grounding regime used. Regulation in an external supply is largely redundant due to the length of the cable from the PSU to the unit being powered (it can help to lower total noise a little bit due to clean power entering the unit but not by much).
For example the Arkless Super Regulator (developed from the Jung/Didden topology but with my own ideas incorporated) used in my latest phono stage, which is under development, has an output impedance of a few micro Ohms at low frequencies.... that's millionths of an Ohm and equivalent to a few mm of thick cable! Remote sense is used to bring this right up to the place it's needed (can only be used properly for fairly short wiring lengths... say 6"). What would be the point of putting it in a separate box with 2 meters of cable and a plug and socket at the end!???

[anthonyTD]

H i Jez,
I tend to agree with a lot of your ramblings, :eyebrows: especially the part about outboard power supplies and regulators to a point, which is why i developed the power supply and regulator circuits in my last preamplifiers and power amps to go exactly where they were needed, ie; as close as physically possible to the circuitry they are feeding etc, however, its not always possible within a set budget to do this properly, hence why some settle for the lesser of evils, by that i mean' taking the potentially noisy parts away from the audio circuitry etc.
Regards,Anthony,TD...
The price of transformers has gone through the roof just lately due to soaring world metal prices... China is forcing prices up. They have approx. doubled in price in the last two years. Although switch mode PSU's are vastly more complicated they use much less metal and so provided they are being mass produced can be cheap.

Some PSU's are indeed over priced of course (ones from the Salisbury area come to mind!).

It is by and large a myth that "special", "exotic" or just huge external PSU's have a large beneficial effect. Virtually no solid state pre amp or phono stage really needs anything more than a wall wart supply (there's another myth exploded :eek:) as the whole power supply quality thing, whilst very real and very important, is entirely dependent on the quality of the internal regulation and grounding regime used. Regulation in an external supply is largely redundant due to the length of the cable from the PSU to the unit being powered (it can help to lower total noise a little bit due to clean power entering the unit but not by much).
For example the Arkless Super Regulator (developed from the Jung/Didden topology but with my own ideas incorporated) used in my latest phono stage, which is under development, has an output impedance of a few micro Ohms at low frequencies.... that's millionths of an Ohm and equivalent to a few mm of thick cable! Remote sense is used to bring this right up to the place it's needed (can only be used properly for fairly short wiring lengths... say 6"). What would be the point of putting it in a separate box with 2 meters of cable and a plug and socket at the end!???

[Arkless Electronics]

Obviously in the case of low level amplification such as a phono stage it would be a very bad idea to have a noisy mains transformer in the same box.... It hasn't stopped some from doing it though! My "rambling" was more about the fallacy that things can be upgraded by changing one external PSU for another when we are talking in terms of something that only draws say 100mA anyway and has regulation internal to the unit being powered ;)


H i Jez,
I tend to agree with a lot of your ramblings, :eyebrows: especially the part about outboard power supplies and regulators to a point, which is why i developed the power supply and regulator circuits in my last preamplifiers and power amps to go exactly where they were needed, ie; as close as physically possible to the circuitry they are feeding etc, however, its not always possible within a set budget to do this properly, hence why some settle for the lesser of evils, by that i mean' taking the potentially noisy parts away from the audio circuitry etc.
Regards,Anthony,TD...

[anthonyTD]

Agreed, :)
And i must say its good to have genuine discussions here on the subject' rather than input from those who will use any opportunity to pedal their wares.:(
Long may it continue :)
A...
Obviously in the case of low level amplification such as a phono stage it would be a very bad idea to have a noisy mains transformer in the same box.... It hasn't stopped some from doing it though! My "rambling" was more about the fallacy that things can be upgraded by changing one external PSU for another when we are talking in terms of something that only draws say 100mA anyway and has regulation internal to the unit being powered ;)

[sq225917]

It's horses for courses though isn't it gents.

I have a phonostage that has +/- shunt regs right by the input stage, so the quality of the external PSU matters much less, as long as raw noise is low and it has sufficient current headroom to feed the shunts then the fact that it doesn't have a miniscule output impedance barely matters. But take the Naim kit that Jez dislikes so much, they tend not to have great local regulation in the amplifier chassis, but they do have quite good regulation, with remarkably low impedance (and simply impeccable grounding) in another chassis close by. The point is that both of these options work well.

A decent regulator needn't be expensive, you can build up a few rails of world class regulation for £50 or thereabouts in modest voltages. Just don't expect the moon on a stick at 400v and 10 amps in a plush chassis for the same money, it ain't gonna happen.

[icehockeyboy]

+1 on the Maplins one, especially the 7A version

I was going to start a new thread to ask this.....I already have one of the linear Mark Grant sells, and am very pleased with it, but as I'm currently re carpeting the whole house, I've had to shelve getting another one, so the Maplin one opens up a possibility, but, should I not get one, where best to have the PSU powering, the Squeezebox, or The Bushmaster?

Currently it's on the SB, with a separate S Booster on the Dac, but would I notice a difference with a complete PSU?

[StanleyB]

If my stand alone DC Linearizer Low Noise Filter works as well as it does as the built in version inside the BM2 then switched mode power supply users will have less to worry about as far as large noise output is concerned. It's in this area that linear power supplies score right now. They don't have that kind of high noise figure compared the SMPS.

[anthonyTD]

If my stand alone DC Linearizer Low Noise Filter works as well as it does as the built in version inside the BM2 then
switched mode power supply users will have less to worry about as far as large noise output is concerned. It's in this area that linear power supplies score right now. They don't have that kind of high noise figure compared the SMPS. SMPS are the devils work...:eek::lol:

[Arkless Electronics]

It's horses for courses though isn't it gents.

I have a phonostage that has +/- shunt regs right by the input stage, so the quality of the external PSU matters much less, as long as raw noise is low and it has sufficient current headroom to feed the shunts then the fact that it doesn't have a miniscule output impedance barely matters. But take the Naim kit that Jez dislikes so much, they tend not to have great local regulation in the amplifier chassis, but they do have quite good regulation, with remarkably low impedance (and simply impeccable grounding) in another chassis close by. The point is that both of these options work well.

A decent regulator needn't be expensive, you can build up a few rails of world class regulation for £50 or thereabouts in modest voltages. Just don't expect the moon on a stick at 400v and 10 amps in a plush chassis for the same money, it ain't gonna happen.

Naims regulation consists of a 10p LM317 and that's your lot... No internal regulation at all in the gear I've looked at! I'm afraid I disagree with you on this one Si.
Of course, things can be built without regulators at all....

[Yomanze]

It is by and large a myth that "special", "exotic" or just huge external PSU's have a large beneficial effect. Virtually no solid state pre amp or phono stage really needs anything more than a wall wart supply (there's another myth exploded :eek:) as the whole power supply quality thing, whilst very real and very important, is entirely dependent on the quality of the internal regulation and grounding regime used. Regulation in an external supply is largely redundant due to the length of the cable from the PSU to the unit being powered (it can help to lower total noise a little bit due to clean power entering the unit but not by much).

This is a really good point. I fitted a very good linear PSU to my Bushmaster, and the effects were subtle. I would say for the outlay worthwhile, but by no means a game-changer. The overall characteristics of the DAC remained.

[Paul Hynes]

An external high quality power supply can be very beneficial to sound quality, as there are a number of supply attributes they can address even if they are remote from the load.

Supply line rejection can be considerably improved lowering noise injection into the signal path and also back onto the mains. I would say this is very significant.

If the external supply provided with the equipment has poor regulation, exhibiting significant voltage fluctuation with varying load current, exchanging this for a high performance power supply can provide a significant sonic improvement due to reduced voltage fluctuation. As an example I measured an LM317 (mentioning no names but in the low noise configuration) with a transient load current of 200ma and the output voltage shift exceeded 100mv with a significant overshoot due to poor transient response and settling time. This voltage deviation and transient overshoot effectively adds to the overall noise level on the incoming power supply. I would say that a 100mv + deviation is pretty noisy and reducing this will be very significant.

Preamps and phono stages may show much lower signal current swings, but it should be born in mind that there will also be significant voltage amplification in these devices, which brings supply interference, from whatever source, back up to significant levels.

It is relatively easy to design regulators that regulate with extremely low output impedance at low frequencies, therefore reducing voltage fluctuations due to load current variation, but try doing that at say 20 MHz or even 100Mhz which is a typical clocking frequency for the ESS9018 Sabre DAC chip. The LM 317 has actually stopped regulating at these frequencies and is completely ineffective as a regulator. In fact it deteriorates rapidly above 1 KHz. Load current transients at these higher frequencies are going to cause very significant voltage fluctuations and capacitive decoupling is not going to provide an absolute solution because it will just re-route the return current path injecting noise elsewhere in the power supply/signal processing system.

If you are powering an item of digital equipment that has clocks busily switching at tens of MHz, you need a regulator with significantly wider bandwidth as well as exceptionally fast transient response and settling time.

Ensuring that the external power supply regulator has very low self-generated noise will also reduce the power supply interference in the signal path.

Using high performance regulation directly at the load point is mandatory for high performance signal processing but nothing is perfect and extending the high performance to the external power supply can be very significant sonically. Marco, Martin Taylor, Andy (Rexton) and others on the forum have experienced this with my SL1200/1210 upgrades.

If the equipment to be powered has poor quality internal regulation, the benefits of high quality external regulation can be significantly diluted, and this is a common problem so it is not surprising that with some equipment the actual improvement is limited. In this instance it will pay to upgrade the internal regulation. Are you listening manufacturers?

Also, the more transparent the system, the easier it will be to hear the power supply changes. So if you are swapping a number of different external power supplies and hearing little difference, question the overall transparency of the signal processing/power supply within the equipment you are powering and even of your system as a whole.

[sq225917]

To be fair Jez the new DR regs are far more than that and a lot of the more advanced gear, 252, 555 etc has local regulation internally.

[Arkless Electronics]

I'm not familiar with those units but all the traditional Naim stuff I've ever had in does indeed have only an LM317 in the PSU, or the power amp that is supplying the pre, and then no further regulation... In fact, as all these units have an RC filter decoupling them from the outside world it is hard to say that any external PSU could possibly have any effect...

[Marco]

...unless when you listen and genuinely hear one, of course! Then, it's back to the drawing board - that is if you trust your ears... ;)

Marco.

[Oldpinkman]

...unless when you listen and genuinely hear one, of course! Then, it's back to the drawing board - that is if you trust your ears... ;)

Marco.

The key to that is "genuinely". I trust my ears - its my mind I worry about. And other peoples. Minds are readily susceptible to influence, and there is no exemption to that rule for HiFi enthusiasts. (Indeed quite the opposite it would appear) ;)

[Marco]

An external high quality power supply can be very beneficial to sound quality, as there are a number of supply attributes they can address even if they are remote from the load.

Supply line rejection can be considerably improved lowering noise injection into the signal path and also back onto the mains. I would say this is very significant.

If the external supply provided with the equipment has poor regulation, exhibiting significant voltage fluctuation with varying load current, exchanging this for a high performance power supply can provide a significant sonic improvement due to reduced voltage fluctuation. As an example I measured an LM317 (mentioning no names but in the low noise configuration) with a transient load current of 200ma and the output voltage shift exceeded 100mv with a significant overshoot due to poor transient response and settling time. This voltage deviation and transient overshoot effectively adds to the overall noise level on the incoming power supply. I would say that a 100mv + deviation is pretty noisy and reducing this will be very significant.

Preamps and phono stages may show much lower signal current swings, but it should be born in mind that there will also be significant voltage amplification in these devices, which brings supply interference, from whatever source, back up to significant levels.

It is relatively easy to design regulators that regulate with extremely low output impedance at low frequencies, therefore reducing voltage fluctuations due to load current variation, but try doing that at say 20 MHz or even 100Mhz which is a typical clocking frequency for the ESS9018 Sabre DAC chip. The LM 317 has actually stopped regulating at these frequencies and is completely ineffective as a regulator. In fact it deteriorates rapidly above 1 KHz. Load current transients at these higher frequencies are going to cause very significant voltage fluctuations and capacitive decoupling is not going to provide an absolute solution because it will just re-route the return current path injecting noise elsewhere in the power supply/signal processing system.

If you are powering an item of digital equipment that has clocks busily switching at tens of MHz, you need a regulator with significantly wider bandwidth as well as exceptionally fast transient response and settling time.

Ensuring that the external power supply regulator has very low self-generated noise will also reduce the power supply interference in the signal path.

Using high performance regulation directly at the load point is mandatory for high performance signal processing but nothing is perfect and extending the high performance to the external power supply can be very significant sonically. Marco, Martin Taylor, Andy (Rexton) and others on the forum have experienced this with my SL1200/1210 upgrades.

If the equipment to be powered has poor quality internal regulation, the benefits of high quality external regulation can be significantly diluted, and this is a common problem so it is not surprising that with some equipment the actual improvement is limited. In this instance it will pay to upgrade the internal regulation. Are you listening manufacturers?

Also, the more transparent the system, the easier it will be to hear the power supply changes. So if you are swapping a number of different external power supplies and hearing little difference, question the overall transparency of the signal processing/power supply within the equipment you are powering and even of your system as a whole.

Hi Paul,

Good to see you posting again - hope all is well in your world :)

An excellent post, mate, full of the technical insight, attention to detail (and for me, most significantly) the lateral thinking you're renowned for! I'd like all electronics designers and equipment manufacturers to read and digest your last two paragraphs, as in my view, some claim too easily that things 'make no difference', when in fact they do, but it's just that they're not digging deep enough to find out exactly WHY!!

As for the bit in bold, you're absolutely right. Who'd have thought that individually regulating different parts of the circuitry inside a Technics SL-1200 or 1210 turntable would have had such a profound effect on its sonic performance, or that employing the use of such a massively over-specified linear external PSU would have had a similar effect - and that the combination of both - would utterly transform what was an already very good turntable into something that is really rather special?

Anthony has heard the sonic benefits of your SR7 PSU and regulator boards, first-hand in his own system (using my T/T), and so I'm sure would confirm my sentiments - and I can state that, incrementally, every one of the external PSUs you offer for the Technics, from the SR3 upwards has, to my ears, unquestionably improved its sonic performance, as I'm sure others who've also experienced this would confirm.

Furthermore, the best linear PSUs don't necessarily need to be hugely expensive, especially when comparing what you charge for an SR7, with what a similar design of that quality would likely cost with a Naim badge on it...!! ;)

However, the message of this thread, as far as I'm concerned, is that THINKING OUTSIDE OF THE BOX, and challenging 'currently accepted wisdom' can pay huge dividends in audio, together with never thinking that everything that needs to be learned in electronics has already been learned, or that what can clearly be heard, yet not currently be measured, is therefore automatically imagined :nono:

One must continue to push the boundaries of what is considered possible and continually strive for excellence - and I applaud you for doing precisely that and, in turn, giving audiophiles and music lovers like me the greatest pleasure from listening to our favourite music.

Marco.

[Marco]

The key to that is "genuinely". I trust my ears - its my mind I worry about. And other peoples. Minds are readily susceptible to influence, and there is no exemption to that rule for HiFi enthusiasts. (Indeed quite the opposite it would appear) ;)

Indeed; that's precisely why the word "genuinely" is there - and so one must test for that in the way that best satisfies one's judgment criteria.

[StanleyB]

...unless when you listen and genuinely hear one, of course! Then, it's back to the drawing board - that is if you trust your ears.
Then it is when it might require a relevant piece of test equipment to be plugged in and the signal turned from an audible into a visual one.

I have a different frequency response in my left ear compared to my right ear, which means that I have to repeat some tests several times and in different ways just so that I can exclude my hearing as the only source of reference, or the only reliable source.

A typical example of where what you hear is not necessarily the same as what others hear is with mains hum at 50 or 60Hz, or the FM pilot signal at 19.5KHz. Some people can hear both of them, some can hear one of them, and some of us can't hear either.

[Marco]

Then it is when it might require a relevant piece of test equipment to be plugged in and the signal turned from an audible into a visual one.


Absolutely, Stan.

The desire for any good electronics designer would be to then try and measure for and find technical reasons that explain the difference/improvement that one is convinced one has *genuinely* heard, rather than automatically dismiss such out of hand, simply because no technical proof currently 'fits' to explain it. This is what is done by those with genuinely inquisitive minds and, IMO, is what separates the best designers from merely the mediocre variety.

However, the *key* in all is this, is at what point do your ears, or your test equipment, act as the FINAL arbiter? ;)

Marco.

[StanleyB]

However, the *key* in all is this, is at what point do your ears, or your test equipment, act as the FINAL arbiter? ;)
I find that it is is far more helpful to have one or more alternative persons listen to the same device and tell me if what they hear, if anything. In the majority of cases I don't tell them in advance what I have heard, and what I need them to confirm. If it is so obvious to me, then surely it must be obvious to hear by others as well, taking into account the likelihood that the person asked for a 2nd opinion might have worse hearing... If nobody else can hear what I hear and the test equipment cannot back me up then I have to back off.

A typical example is an experimental asynchronous SPDIf to I2S data processing method first tried out in full in a couple of specially modified Bushmaster DACs. I didn't let the testers know what I was up to, and whether they should or should not hear a difference. But low and behold, MartinT picked it up within a couple of hours of listening to the modified DAC that he tried. He even mentioned it in passing in a thread, but only one other person even noticed what he had written... Most of the other lot noticed an improvement, but were not sure if it was their mind or their hearing. And they still have no clue what it was all about...

[MartinT]

A typical example is an experimental asynchronous SPDIf to I2S data processing method first tried out in full in a couple of specially modified Bushmaster DACs. I didn't let the testers know what I was up to, and whether they should or should not hear a difference. But low and behold, MartinT picked it up within a couple of hours of listening to the modified DAC that he tried.

It's good to know what you actually did with that firmware, Stan. The really good news is that my Bushmaster has been sounding exceptionally good ever since.

Is that firmware going into the Mk. II?

[StanleyB]

Is that firmware going into the Mk. II?
That's why I needed to have it tested before daring to add it to the new BM;).

[anthonyTD]

hi Marco,
Both Paul and myself realized there was more to be had from the 1210 by regulating individual parts of the circuitry, and as you know' we had a few discussions on the subject, and as you say, the performance upgrade was well worth the effort of the work involved etc, however, my point on outboard power supplies i feel may have been over-looked, well designed linear power supplies in general can have a significant affect, however, they will not make a badly designed piece of kit sound any better, also, any benefits an upgraded power supply may have, will only be fully achieved by addressing the failings in the rest of the units power supply related parts and design. also, As Paul has quite rightly pointed out, good regulator design must include ultra low impedance, and therefore high noise rejection characteristics way' way out of the audio frequency bandwith and beyond' to be of any significant improvement over a standard LM317 and including all of the common 5 to 24v regs found in most equipment power supplies. [which is why i don't use any of them in my own dedicated power supply designs] Which brings me back to my point, from my own findings, and tests etc, well designed power supplies be they in-board or out, have the capability to improve the sonic capabilities of the equipment, but their full potential can only be realized by optimizing the rest of the following power supply elements within the equipment.
Anthony,TD..
Hi Paul,

Good to see you posting again - hope all is well in your world :)

An excellent post, mate, full of the technical insight, attention to detail (and for me, most significantly) the lateral thinking you're renowned for! I'd like all electronics designers and equipment manufacturers to read and digest your last two paragraphs, as in my view, some claim too easily that things 'make no difference', when in fact they do, but it's just that they're not digging deep enough to find out exactly WHY!!

As for the bit in bold, you're absolutely right. Who'd have thought that individually regulating different parts of the circuitry inside a Technics SL-1200 or 1210 turntable would have had such a profound effect on its sonic performance, or that employing the use of such a massively over-specified linear external PSU would have had a similar effect - and that the combination of both - would utterly transform what was an already very good turntable into something that is really rather special?


Anthony has heard the sonic benefits of your SR7 PSU and regulator boards, first-hand in his own system (using my T/T), and so I'm sure would confirm my sentiments - and I can state that, incrementally, every one of the external PSUs you offer for the Technics, from the SR3 upwards has, to my ears, unquestionably improved its sonic performance, as I'm sure others who've also experienced this would confirm.

Furthermore, the best linear PSUs don't necessarily need to be hugely expensive, especially when comparing what you charge for an SR7, with what a similar design of that quality would likely cost with a Naim badge on it...!! ;)

However, the message of this thread, as far as I'm concerned, is that THINKING OUTSIDE OF THE BOX, and challenging 'currently accepted wisdom' can pay huge dividends in audio, together with never thinking that everything that needs to be learned in electronics has already been learned, or that what can clearly be heard, yet not currently be measured, is therefore automatically imagined :nono:

One must continue to push the boundaries of what is considered possible and continually strive for excellence - and I applaud you for doing precisely that and, in turn, giving audiophiles and music lovers like me the greatest pleasure from listening to our favourite music.

Marco.

[Marco]

I find that it is is far more helpful to have one or more alternative persons listen to the same device and tell me if what they hear, if anything. In the majority of cases I don't tell them in advance what I have heard, and what I need them to confirm. If it is so obvious to me, then surely it must be obvious to hear by others as well, taking into account the likelihood that the person asked for a 2nd opinion might have worse hearing... If nobody else can hear what I hear and the test equipment cannot back me up then I have to back off.


Absolutely, which is why beta testing works so well! Also, if your chosen listeners are successfully identifying issues, unprompted, that you yourself suspect exist, then there's a good chance that they're not being imagined! ;)

Marco.

[Marco]

..however, my point on outboard power supplies i feel may have been over-looked, well designed linear power supplies in general can have a significant affect, however, they will not make a badly designed piece of kit sound any better, also, any benefits an upgraded power supply may have, will only be fully achieved by addressing the failings in the rest of the units power supply related parts and design. also, As Paul has quite rightly pointed out, good regulator design must include ultra low impedance, and therefore high noise rejection characteristics way' way out of the audio frequency bandwith and beyond' to be of any significant improvement over a standard LM317 and including all of the common 5 to 24v regs found in most equipment power supplies. [which is why i don't use any of them in my own dedicated power supply designs] Which brings me back to my point, from my own findings, and tests etc, well designed power supplies be they in-board or out, have the capability to improve the sonic capabilities of the equipment, but their full potential can only be realized by optimizing the rest of the following power supply elements within the equipment.


Absolutely, mate - and indeed that's precisely what Paul was saying. Unfortunately, however, some electronics designers, IME, have the tendency to dismiss differences as not being possible and/or 'imagined', simply because they've failed to look at the 'bigger picture', the concept of which you've neatly outlined above! ;)

Genuine upgrades to audio equipment should always be judged on the sonic effect of the SUM of their parts, and not simply on whether the influence of certain components on their own, within a design (such as high-quality linear PSUs), can be proven individually for their efficacy. When it comes to circuits, one must always analyse or judge the WHOLE :)

Marco.

[Arkless Electronics]

It's the regulation that makes the difference, not the "power supply" as such. The grounding is also just as important as it is the combination of good grounding and good regulation that gives the pure, clean and "stiff" voltage to the circuitry that is desired. I guess Marco and I will just have to agree to disagree as I'm obviously his idea of a bad engineer.... I know what's possible and what's impossible and I don't waste my time pursuing the impossible but rather prefer to try and perfect the possible ;)

[Oldpinkman]

Absolutely, mate - and indeed that's precisely what Paul was saying. Unfortunately, however, some electronics designers, IME, have the tendency to dismiss differences as not being possible and/or 'imagined', simply because they've failed to look at the 'bigger picture', the concept of which you've neatly outlined above! ;)

Genuine upgrades to audio equipment should always be judged on the sonic effect of the SUM of their parts, and not simply on whether the influence of certain components on their own, within a design (such as high-quality linear PSUs), can be proven individually for their efficacy. When it comes to circuits, one must always analyse or judge the WHOLE :)

Marco.

Marco - I don't think that's what he's saying at all, and I don't think that it is true. What he appears to be saying, and what I am sure most would agree with, is that an improved component may be a genuine improvement, but you will only hear it if the rest of your system is good enough. If you put a top moving coil cartridge, with a top MC phono stage, and feed it into a £50 mini-system you may not hear the difference from a cheap £10 moving magnet cartridge - but the moving coil set up is still honestly better, even though you can't hear it in that system.

HOWEVER, once you have a decent system which allows small differences to be apparant you WILL hear it quite separately. If you can't hear that component change making a difference in your high quality reference system then its not making a difference. Somehwere, to know it makes a difference, you have to be able to hear it when you change just one component. Of course, you can get complex interactions between components, and may prefer combinations, but any item making a genuine difference will distinguish itself in a decent reference system.

In the context of power supplies, a good regulated supply will not in itself overcome poor design within the equipment it is supplying. Thats not the same as saying that the effect of a good DC supply can't be demonstrated in the right equipment by comparing it with a poorer supply in the same equipment. Individually as one component.

:)

[Marco]

I guess Marco and I will just have to agree to disagree as I'm obviously his idea of a bad engineer....


Hi Jez,

Not at all, simply because I have no basis from which to form such an opinion, i.e. I haven’t listened to anything you've made! ;)

Outside of mundane (but essential) things, such as functionality, safety, reliability, etc, there is ONE thing, and ONE thing only that I judge equipment on, and that's out-and-out sonic performance, and crucially, how that impacts on my enjoyment of listening to my favourite music. If an audio designer can continually produce equipment that impresses me on that level, then he or will always have my utmost respect :)

All I would say is that you don't always know what's possible until you try!!

Marco.

[StanleyB]

I know what's possible and what's impossible and I don't waste my time pursuing the impossible but rather prefer to try and perfect the possible ;)
I am glad that Dyson, the Wright brothers and many others were far more open minded. I pursued the seemingly impossible on many occasions, even when my fellow engineers were telling me I was wasting my time. But we now have TV signal amplifiers that can be adjusted for gain remotely and be made for less than U$5, amongst many others. It didn't make me any money (but my previous employer is), but I did prove that it wasn't impossible as so many leading RF designers had been claiming.

[Marco]

In the context of power supplies, a good regulated supply will not in itself overcome poor design within the equipment it is supplying. Thats not the same as saying that the effect of a good DC supply can't be demonstrated in the right equipment by comparing it with a poorer supply in the same equipment. Individually as one component.


Indeed, Richard. However, we're slightly at cross purposes, perhaps because I didn't explain myself properly.

What I'm saying is that I believe it's folly to automatically think that, say, a massively over-specified PSU can't produce significant sonic benefits within a given circuit, simply because 'commonly accepted wisdom'/science says not. One must examine things more deeply, in that respect, and look beyond the 'immediately obvious'.

Jez, Anthony and Paul are right about "it's the regulation that makes the difference, not the 'power supply' as such." However, despite that, who'd have thought Paul's hugely over-specified (and some would argue) technically 'unnecessary' PSUs, for the SL-1200/1210, would deliver such significant sonic upgrades - and yet unquestionably, to my ears and those of others, they do!

The interesting thing, which backs up what the designers present here are saying about the importance of regulation, is that I got Paul's SR7 PSU first, before I had the individual regulation modules fitted to my Techy, and whilst the SR7 offered a pretty obvious sonic upgrade, over the smaller SR5 PSU that preceeded it, it wasn't until I had the regulator boards fitted, and both worked as a pairing, that the REALLY BIG sonic improvements were heard!! :exactly:

Therefore, the fact is that both the huge PSU (SR7) and regulator boards combined, with the circuit in the Techy (AS A WHOLE), to great effect - and that this would not have been possible had Paul not looked beyond the technically 'immediately obvious' and challenged 'currently accepted wisdom' :)

Marco.

[Canetoad]

That's why I needed to have it tested before daring to add it to the new BM;).

Stan,

Is the firmware update available for the BM version 1?

[Arkless Electronics]

I am glad that Dyson, the Wright brothers and many others were far more open minded. I pursued the seemingly impossible on many occasions, even when my fellow engineers were telling me I was wasting my time. But we now have TV signal amplifiers that can be adjusted for gain remotely and be made for less than U$5, amongst many others. It didn't make me any money (but my previous employer is), but I did prove that it wasn't impossible as so many leading RF designers had been claiming.

There is an infinite void between the possible... but very difficult/a bit leftfield/untried in a particular application etc etc and the impossible! I to have on many occasions solved problems that fellow engineers and even some text books said were very difficult/not worth pursuing/impractical but I would not waste my time on something that is patently impossible.
The Wright brothers, Dyson etc merely pursued new and untried applications for known physical laws. They did not attempt to break the laws of physics.

For example (and this is one that really gets up the noses of the "but I can hear it" brigade) there is absolutely no way a fancy mains lead can improve sound quality. It's simply impossible and against the laws of physics..... as well as simple reasoning. So, it is something I would not waste even a minute of my time on.

Remote controlling the gain of an RF amp has been straightforward for decades BTW!

Anyway I'll bow out of this thread now as I have found on many occasions that telling the truth and exploding myths about hifi does not exactly win one any friends... and I've better things to do than get into pointless and probably circular arguments.

[Marco]

The Wright brothers, Dyson etc merely pursued new and untried applications for known physical laws. They did not attempt to break the laws of physics.


No, they challenged the (then accepted) laws of physics, and did it successfully - that's the difference! ;)

The only way that man will continue to make new discoveries, and evolve, is to continue challenging and attempting to supersede 'currently accepted wisdom'. That is precisely what the best audio designers (and REAL scientists) do, or anyone with a genuinely inquisitive mind: they 'go the extra mile' and believe in thinking 'outside of the box', which can (and does) often provide dividends.


For example (and this is one that really gets up the noses of the "but I can hear it" brigade) there is absolutely no way a fancy mains lead can improve sound quality. It's simply impossible and against the laws of physics..... as well as simple reasoning. So, it is something I would not waste even a minute of my time on.


Lol... Best not go there!!


Anyway I'll bow out of this thread now as I have found on many occasions that telling the truth and exploding myths about hifi does not exactly win one any friends... and I've better things to do than get into pointless and probably circular arguments.

Only bow out if you want to and/or have other things to do, because frankly I enjoy reading your take on things, even if we don't always agree... Diversity of opinion is good, as long as there is politeness and mutual respect between all parties.

Marco.

[StanleyB]

Remote controlling the gain of an RF amp has been straightforward for decades BTW!

Not in a U$5 design. My then boss was so impressed by the sudden worldwide interest in my invention that he bought up Labgear (remember them?) to increase production and have a better brand name.

[Oldpinkman]

For example (and this is one that really gets up the noses of the "but I can hear it" brigade) there is absolutely no way a fancy mains lead can improve sound quality. It's simply impossible and against the laws of physics..... as well as simple reasoning. So, it is something I would not waste even a minute of my time on.



Hey, Hey, Hey - get in the queue will you? Having voiced similar views about mains cables, and received stony silence regarding scientific explanations for their effect, or convincing reliable evidence of their efficacy regardless of a scientific explanation, I am about to try some to permit me to resume using the "S" word. Or not.

And Stan, I am trying hard to stay friends here, but James Dyson not only didn't attempt to buck the laws of physics, he didn't even discover or invent the cyclonic filter - he just championed its application in a domestic vacuum cleaner. The issue wasn't whether it worked - it was whether anyone wanted it. Or rather - should be allowed to want it. Like I said, Pritchitt Foods who I once worked for were spinning milk powder into silos using cyclones way back before WW2. The objection was a marketing one - the loss of revenue from hoover bags as regular consumables to be replaced. At that time, the UK market for disposable cleaner bags was £100 million.;)

[MCRU]

Hey, Hey, Hey - get in the queue will you? Having voiced similar views about mains cables, and received stony silence regarding scientific explanations for their effect, or convincing reliable evidence of their efficacy regardless of a scientific explanation, I am about to try some to permit me to resume using the "S" word. Or not.

And Stan, I am trying hard to stay friends here, but James Dyson not only didn't attempt to buck the laws of physics, he didn't even discover or invent the cyclonic filter - he just championed its application in a domestic vacuum cleaner. The issue wasn't whether it worked - it was whether anyone wanted it. Or rather - should be allowed to want it. Like I said, Pritchitt Foods who I once worked for were spinning milk powder into silos using cyclones way back before WW2. The objection was a marketing one - the loss of revenue from hoover bags as regular consumables to be replaced. At that time, the UK market for disposable cleaner bags was £100 million.;)

tell me please why the doubters need evidence to tell them what their ears are hearing? if you read a convincing technical paper on this subject at the same time as listening to your music would that help to make the system sound better?

[Oldpinkman]

tell me please why the doubters need evidence to tell them what their ears are hearing? if you read a convincing technical paper on this subject at the same time as listening to your music would that help to make the system sound better?

No - I said a technical paper or evidence their ears are hearing it. I have had lots of worthy assurances that they do really hear it. I used to get lots of worthy assurances people could tell the direction on directional inter-connects too. Nobody ever managed it. I am going to try 2 mains leads - seriously. One for my preamp, one for the power, both direct to the mains socket to cut out the influence of the multi-way which I would normally use for convenience. With a battery powered Pink Triangle. If I hear a difference, I shall be banging on the door of my techies to explain it.

If I don't hear a difference, I shall shift the onus of proof onto the "faithfull" for them to demonstrate to me that they can hear the difference. There have as yet been no takers for providing a convincing demo. It has been in the nature of our scientific progress through the years that new discoveries explain previously mysterious phenomena - and previous scientific theories and dogma have been overturned. Newton's gravity was revised by Einstein. I remain open minded - but skeptical due to the reliance on "just believe me" from the faithful.

But an explanation or proof. Verifiable reliable consistent proof under reasonable controlled experimental conditions (blind test). Not assurances, and puff. And who knows - I first asked the question of my "guru" as Gordon calls him, when I was considering trying shielded mains to tackle a hum issue in my signal cables. His response was not "absolutely impossible" but, to paraphrase - "highly improbable and arse-about-face"

[Gordon Steadman]

No - I said a technical paper or evidence their ears are hearing it. I have had lots of worthy assurances that they do really hear it. I used to get lots of worthy assurances people could tell the direction on directional inter-connects too. Nobody ever managed it. I am going to try 2 mains leads - seriously. One for my preamp, one for the power, both direct to the mains socket to cut out the influence of the multi-way which I would normally use for convenience. With a battery powered Pink Triangle. If I hear a difference, I shall be banging on the door of my techies to explain it.

I fear that whilst there are people in this world who genuinely believe that they have seen tears or blood coming from a stone statue and the like, I shall put all effects that I can't hear down to wishful thinking (or possibly increasing deafness:eek:). I am happy to use my ears to choose my equipment so continue to believe them when it comes to rejecting those things I consider a waste of my hard earned. If others want to shell out on things that I consider snake oil, that is their affair.

I do get a bit peed off with being told that my 'inability' is down to my inferior system. I have a standard answer which I am much too polite to repeat in public.

However, as Richard says, I would expect there to be a reasonable explanation for any effects and no-one seems to be able to give any for most of the 'black art' effects. I can't recall taking anything on faith for a long long time. I guess I'm just an old cynic.

[Oldpinkman]

No, they challenged the (then accepted) laws of physics, and did it successfully - that's the difference! ;)



Marco.

Marco - I've just noticed you on this one too. I commented on Stans comment prior to this post, and took issue with him earlier in the year for this sort of melodrama that is typical of the "fidei defensor" - but you are being imprecise with your language too. James Dyson DID NOT challenge the laws of physics. At all. He used well established documented scientific physics, which had already been demonstrated to work in industrial silos for years before his vacuum cleaner - including at the factories I worked at. He challenged a marketing block. Hoover and other "hoover" manufacturers had discovered a fabulous new market for consumables, worth at the time £100m in the UK, for disposable bags to replace the cloth bags previously used in conventional vacuums. They didn't believe there was a market for a bagless cleaner - or rather didnt believe such a market should be allowed. But there was no challenge to conventional science - and certainly no challenge to "then accepted" laws of physics. :rolleyes:

[MCRU]

Thread drift, back to linear power supply's please as it's my number one selling product line....strange that one, as you could argue they don't make the music sound better either but 1000's of customers who use them can't all be fools or deaf or some other derogatory remark given to people who can genuinely hear improvements from mains related products! Present company excluded of course.

BTW when did anyone go to a motorway service station toilet or a cinema recently, the dyson copying of an air hand dryer is now gaining popularity.!

[Oldpinkman]

Thread drift, back to linear power supply's please as it's my number one selling product line....strange that one, as you could argue they don't make the music sound better either but 1000's of customers who use them can't all be fools or deaf or some other derogatory remark given to people who can genuinely hear improvements from mains related products! Present company excluded of course.

BTW when did anyone go to a motorway service station toilet or a cinema recently, the dyson copying of an air hand dryer is now gaining popularity.!

Fair cop. I may well be checking one out as part of project "pimp-PT" since I have no problem with the way a linear power supply can potentially affect audio (although waiting to see it demonstrated on the old TT when the other mods justify it) :)

Sorry for getting sucked up in the hijack - it's a weakness :doh:

[Marco]

Hi Richard,

Ok, let's say that the Wright brothers pushed the boundaries of what was previously considered possible and achieved something that no-one else in their field at that point had done, and that Dyson successfully applied some lateral thinking that changed forever the (then established) design of a major domestic product.

The point is that they were both revolutionaries in their respective fields, and they achieved that by challenging the 'accepted norm'. It is this challenging of the 'accepted norm' I'm advocating and consider as crucial, in terms of our ability to learn and evolve, which in terms of audio design, demands genuinely inquisitive minds and a willingness to push boundaries and apply lateral thinking - and most importantly - a desire also to challenge 'currently accepted wisdom'.

It is my opinion that the best audio electronics designers are those who fully embrace those principles. Will that do, sir? :ner:

Marco.

[MCRU]

Hi Richard,

Ok, let's say that the Wright brothers pushed the boundaries of what was previously considered possible and achieved something that no-one else in their field at that point had done, and that Dyson successfully applied some lateral thinking that changed forever the (then established) design of a major domestic product.

The point is that they were both revolutionaries in their respective fields, and they achieved that by challenging the 'accepted norm'. It is this challenging of the 'accepted norm' I'm advocating and consider as crucial, in terms of our ability to learn and evolve, which in terms of audio design, demands genuinely inquisitive minds and a willingness to push boundaries and apply lateral thinking - and most importantly - a desire also to challenge 'currently accepted wisdom'.

It is my opinion that the best audio electronics designers are those who fully embrace those principles. Will that do, sir? :ner:

Marco.

:clapclapclap:

[Oldpinkman]

:clapclapclap:

Hey - I've just started a new thread to stop hijacking this thread http://theartofsound.net/forum/showthread.php?27752-Mains-cables-myths-magic-laws-of-physics-and-dambusters&p=478220#post478220

My reply to Marco is there. Make your f.... mind up MCRU - on this thread or off it?

Richard :steam:

[Arkless Electronics]

I am currently developing a fairly high end phono stage, MC only, in which the power supply is absolutely critical. However as this is all taken care of internally I am perfectly happy to use a wall wart to power it, and that's what will be provided with it. There will be zero improvement from using anything better. Nuff said ;)

[MCRU]

Richard,

chill out, go and listen to some music and calm down, quite frankly another mains cable thread is boring and won't invite anything new or anything that has not been said before and tbh who cares anyway?

[Marco]

My reply to Marco is there. Make your f.... mind up MCRU - on this thread or off it?

Richard :steam:

Oi, old chap, don't get stroppy! ;)

I'll get to your new thread after din-dins.

Marco.

[Marco]

I am currently developing a fairly high end phono stage, MC only, in which the power supply is absolutely critical. However as this is all taken care of internally I am perfectly happy to use a wall wart to power it, and that's what will be provided with it. There will be zero improvement from using anything better. Nuff said ;)

Is that because you've deliberately engineered the circuit in such a way that it can't take advantage of anything better? ;) ;)

Marco.

[sq225917]

I am currently developing a fairly high end phono stage, MC only, in which the power supply is absolutely critical. However as this is all taken care of internally I am perfectly happy to use a wall wart to power it, and that's what will be provided with it. There will be zero improvement from using anything better. Nuff said ;)


I'd let your customers be the judge of that. Unless of course alienating them before the product goes on sale is more important than sales ;-)

[Marco]

Gotta agree with that...

Jez, since you're into circulating your kit to members for evaluation (as you've already done on pfm with your other designs), if you send me one of the phono stages in question, I'll review it and post my findings here.

Never mind whether a 'fancy' linear PSU would improve it or not, all I'd be interested in is evaluating its qualities as a high-end MC phono stage. So what do you say? :)

Marco.

[Arkless Electronics]

Is that because you've deliberately engineered the circuit in such a way that it can't take advantage of anything better? ;) ;)

Marco.

Sometimes I feel the despair of the explorer repeatedly trying to explain to the uneducated natives that no the camera won't take their soul away.....

PROVIDED an item of hifi equipment is CORRECTLY DESIGNED there will BE NO IMPROVEMENT FROM A "BETTER" EXTERNAL SUPPLY. Only when the unit being powered is so crude as to lack proper internal smoothing and regulation will there be an improvement. Even if lowly 78xx series or LM317 etc are used as the regulators (90% of cases) they have a low frequency power supply rejection ratio (PSRR) of around 80dB which means that any "rubbish" on the incoming voltage will be rejected by a factor of 10,000:1!! At high frequencies proper decoupling capacitor practice will do the job.
I am mainly talking here about fairly simple power requirements such as 12 or 24 V DC or even AC.... If something uses an AC supply then any external supply has even less to do as it's all now entirely to do with the main unit!
Obviously sometimes an item will need a fairly large and complicated external PSU, such as a valve amp that will need HT and a filament supply and may in fact need separate "floating" supplies for the heaters of cascode stages etc. If it's properly designed though the final say in power quality will be within the main unit.

Yes no doubt 90% of people will now think I'm talking out of my arse due to the vast amount of hearsay, rumours, reviews, dealer speak and forum chatter that says the opposite. There is a big market for supposed "special" PSU's and therefore a vast amount of interested parties that make money from it and continue to promote utter bollocks. I am poorer than a church mouse and could no doubt make a killing from selling interconnects, mains cables, after market PSU's, green pens and oak feet for amps but I wouldn't be able to sleep at night. I refuse to play "the game" that the whole industry has bought into as it's business plan in which after Sir has purchased his expensive hifi he has then to be conned into a spurious upgrade path of bigger and better external PSU's, stands for amps, foo mains cables etc. When a lie is told so many times that 90% of the people believe it to be true it remains a lie.....even if one then has to swim against the tide to persuade anyone of it! Yep I'm a crap businessman.... But, I like to think, a good engineer.

[Arkless Electronics]

I'd let your customers be the judge of that. Unless of course alienating them before the product goes on sale is more important than sales ;-)

If my customers wish to use a "better" PSU with it then they are obviously welcome to.... they may even imagine that it sounds better :eyebrows:

[Arkless Electronics]

Gotta agree with that...

Jez, since you're into circulating your kit to members for evaluation (as you've already done on pfm with your other designs), if you send me one of the phono stages in question, I'll review it and post my findings here.

Never mind whether a 'fancy' linear PSU would improve it or not, all I'd be interested in is evaluating its qualities as a high-end MC phono stage. So what do you say? :)

Marco.

The point is that the internal regulators are so "fancy" that you can feed it any old crap from the PSU and it will make no difference!! Hence I have no hesitation in using wall wart type supplies (or the bigger in-line type often used with printers etc if more current is needed).

In principle, yes I would like to send you a unit for evaluation. It would be a prototype unit and so not to be judged on either it's internal or external appearance!

You could even see what type of interconnects you imagine it to work best with! :D

[Marco]

Lol... Nice one. I look forward to that. Keep me posted on developments :)

As for the content of your post #65, it's probably best not to go there. For me, at the end of the day, as an end user of product, the proof of the pudding (as it were) is ALWAYS in the listening. I let the designers of equipment worry about all the other bollocks!!! ;)

Marco.

[Stubies]

Wow, I think this got the tail of a lion! ;)
:goodthread:
This thread had been a fabulous education for me. Much I didn’t know (and didn’t know I didn’t know) or even imagine. Terrific discussion!

This thread may not be finished, nonetheless, I have some conclusions for myself.

Ultimately, and inevitably: My Future has a shelf full of PSUs. :doh:

The problem is PSUs delivered with most equipment will simply not deliver the 'best result' IMHO and, sometimes, not even a very good result. (Notwithstanding that some equipment has internal PSU regulation weaknesses additionally, and that the best internal PSU regulation can still be flagged by a weak external PSU). This is based on my own experience, of course, which for me has been conclusive.

Furthermore, a bake-off without upgraded PSU’s is incomplete – thus the inevitability of the PSU shelf. And when you don’t know if you will keep the equipment, this makes the bake-off a more expensive proposition.:rolleyes:

I certainly have heard differences from upgrading from SMPSs to linear PSUs. For example using a Mark Grant PSU for the Bushmaster – for me this was a change from ‘very good to ‘wow I love it’.

I look at it this way: Admittedly the PSU upgrade ‘listening difference’ was small, but the emotional satisfaction was big. IMO

And for the benefit of the scientifically mined, thus the third conclusion is: Emotional satisfaction is not linear. ;)


=>insert 'Eureka Emoticon' of Archimedes running from his bath!

[Arkless Electronics]

Here's an example of where a good external linear PSU WILL do the trick. Those little T amp modules that give about 6 WPC and have no internal regulation... Maybe some cheapo headphone amps would have no internal regulation and then they too would benefit. It's possible some turntables that use a DC motor may not have internal regulation..... If I think of any more I'll add them to the list!

[Arkless Electronics]

Wow, I think this got the tail of a lion! ;)
:goodthread:
This thread had been a fabulous education for me. Much I didn’t know (and didn’t know I didn’t know) or even imagine. Terrific discussion!

This thread may not be finished, nonetheless, I have some conclusions for myself.

Ultimately, and inevitably: My Future has a shelf full of PSUs. :doh:

The problem is PSUs delivered with most equipment will simply not deliver the 'best result' IMHO and, sometimes, not even a very good result. (Notwithstanding that some equipment has internal PSU regulation weaknesses additionally, and that the best internal PSU regulation can still be flagged by a weak external PSU). This is based on my own experience, of course, which for me has been conclusive.

Furthermore, a bake-off without upgraded PSU’s is incomplete – thus the inevitability of the PSU shelf. And when you don’t know if you will keep the equipment, this makes the bake-off a more expensive proposition.:rolleyes:

I certainly have heard differences from upgrading from SMPSs to linear PSUs. For example using a Mark Grant PSU for the Bushmaster – for me this was a change from ‘very good to ‘wow I love it’.

I look at it this way: Admittedly the PSU upgrade ‘listening difference’ was small, but the emotional satisfaction was big. IMO

And for the benefit of the scientifically mined, thus the third conclusion is: Emotional satisfaction is not linear. ;)


=>insert 'Eureka Emoticon' of Archimedes running from his bath!

You can lead a horse to water but you can't make it drink ;)

Upgrading the internal regulation and smoothing of your equipment will make a much bigger difference than any external PSU....

In my latest phono stage there is RC filtering at the input (after RF filtration) which will reduce nasty stuff by about 50 times, then there is pre-regulation by LM317 (arranged to auto track the input voltage) which does it by about 10.000 times.... so thats 500,000 times reduction... then there is the Super Regulator which will reduce it by about 1000,000 times further.... so that's a total of 500,000,000,000:1 reduction of any crap coming into the unit. That's why any old PSU will do externally ;) And after all that some folks think a mains lead is going to improve it.. nah, it ain't.

[MartinT]

Here's an example of where a good external linear PSU WILL do the trick. Those little T amp modules that give about 6 WPC and have no internal regulation...

Been there, done that. My T-Amp on my PC responded extremely well to a Paul Hynes linear PSU (see my thread elsewhere). In fact, that T-Amp & PSU combo give extraordinarily good performance and challenge some quite serious midrange kit.

[sq225917]

jez, it makes more sense when you detail it out like that. Without the explanation that it already has many sequential stages of regulation, smoothing and filtering most people just assume it can do with some more. I believe the phrase over egging the pudding would be suitable.

When you have one built up let me know, I'll pop up with the Paradise and we can compare and contrast. I also have a MF A100 belonging to a mate that needs your attention.

[Stubies]

You can lead a horse to water but you can't make it drink ;)

Upgrading the internal regulation and smoothing of your equipment will make a much bigger difference than any external PSU....

In my latest phono stage there is RC filtering at the input (after RF filtration) which will reduce nasty stuff by about 50 times, then there is pre-regulation by LM317 (arranged to auto track the input voltage) which does it by about 10.000 times.... so thats 500,000 times reduction... then there is the Super Regulator which will reduce it by about 1000,000 times further.... so that's a total of 500,000,000,000:1 reduction of any crap coming into the unit. That's why any old PSU will do externally ;) And after all that some folks think a mains lead is going to improve it.. nah, it ain't.


Jez,

I am by no means competent to debate the technical issues in this thread. And I do believe and appreciate that your internal regulation has a big impact on the SQ!

Nonetheless, that wont stop me from having an opinion :lol:


Here is a question to test: "Can the internal regulation be so good it becomes exclusive to all other power input factors?"


Currently, im not convinced. For example, can the SQ change with an external PSU of higher voltage/higher amperage? I believe yes.

Thus even if the internal regulation is tops – you may still want to try it with different PSUs. And in most cases, you are not so certain the internal regulation is that great, afterall.


Therefore, when testing new equipment, the net result is still the same. You will want to try it with a different PSU as well, and inevitably those PSU critters will multiply in your closet.

[Arkless Electronics]

Jez,

I am by no means competent to debate the technical issues in this thread. And I do believe and appreciate that your internal regulation has a big impact on the SQ!

Nonetheless, that wont stop me from having an opinion :lol:


Here is a question to test: "Can the internal regulation be so good it becomes exclusive to all other power input factors?"


Currently, im not convinced. For example, can the SQ change with an external PSU of higher voltage/higher amperage? I believe yes.

Thus even if the internal regulation is tops – you may still want to try it with different PSUs. And in most cases, you are not so certain the internal regulation is that great, afterall.


Therefore, when testing new equipment, the net result is still the same. You will want to try it with a different PSU as well, and inevitably those PSU critters will multiply in your closet.

YES! :)

[MartinT]

NO!!

No power supply on earth has infinite PSRR and CMRR.

[Arkless Electronics]

NO!!

No power supply on earth has infinite PSRR and CMRR.

YES!!

It is not difficult to get things so that no further improvement can come from the quality of the incoming power. Of course things can be cocked up or done on the cheap to the extent that a good linear supply will make an improvement but I'm referring to cases where good engineering practice has been used.

At the end of the day people will do as they wish and buy what they want of course and are free to let their imagination run wild!

[Marco]

Just to be different, I'll go for a maybe... :eyebrows:

Marco.

[MartinT]

Your answer for the real world is closer than you think, Marco! Of course, if you have designed your internal regulators well, then its rejection of external power supply nastiness (PSRR) can be such that it reduces the problem to negligible. However, it's important to recognise that some of it will still get through.

[Paul Hynes]

The LM317 supply line rejection is usually quoted as 80dB (10,000 times reduction) at 100Hz but above approx 500Hz to 1KHz the rejection falls due to a reduction in available negative feedback. With a 10uf Capacitor on the adjustment terminal for noise and ripple reduction the manufacturers of these devices typically quote 70 dB (3,162 times reduction) at 10KHz, 40 dB (100 times reduction) at 100KHz and 20 dB (10 times reduction) at 1MHz. At 10MHz you might as well just wire it out, as it will be serving no useful function. In fact wiring it out will probably be of benefit at 10MHz as the chip circuitry will no longer be in series with the power feed. Another effect caused by this reducing loop gain is a steady rise in output impedance with increasing frequency which, for a given load current change, causes more output voltage variation with increased frequency.

Of course it is relatively easy to design a “super regulator” that exceeds the performance of the LM317, however I would be very surprised if it’s supply line rejection of 120dB (1,000,000 times) could be maintained to 1MHz. As low noise amplifiers typically used for “super regulators” have a similar frequency dependant reduction in available negative feedback to the LM317. Some may achieve a higher open loop –3dB bandwidth than the LM317 but as soon as you reach this –3dB bandwidth limit it is downhill from that point.

So theoretically a 214dB (500,000,000,000 times reduction) would only be valid up to 1 KHz due to the LM317 and the frequency dependant supply line rejection of the “super regulator” would also contribute to the reduction in supply line rejection above it’s -3dB open loop gain roll off point, which may higher or lower than the LM317. This means that supply line rejection will be falling rapidly with increasing frequency.

There is a lot of HF noise on the mains supplies nowadays from a wide variety of sources. The mains earth is rarely an effective RF earth (or even an effective audio frequency earth) and this can reduce the effectiveness of RF filters, and also supply decoupling capacitors, allowing system power line and ground modulation at high frequencies. As typical equipment voltage regulators are becoming less effective dealing with supply line rejection at higher frequencies, supply line noise break through at higher frequencies is a common occurrence and it can break through into signal processing circuits (their supply line rejection is also reducing at high frequencies) causing distortion and inter-modulation with signals.

One reason why a high quality external power supply with extended high frequency supply line rejection can provide a noticeable improvement in sound quality as it provides another wall of rejection to interference. Of course different design solutions used in different items of equipment will vary the result depending on their level of effectiveness. However I sell al lot of external power supplies, for a very wide variety of audio equipment, and I do not get returns due to sound quality issues. If my external power supply upgrade offerings were providing no benefit in sound quality I would be swamped with returns and out of business very quickly.

[Marco]

It would be interesting if Jez could challenge the above, technically, particularly what's written in the last two paragraphs.

Well, Jez? ;)

I particularly like this, from Paul, as an excellent example of lateral thinking:


"One reason why a high quality external power supply with extended high frequency supply line rejection can provide a noticeable improvement in sound quality as it provides another wall of rejection to interference."


Nice one! :)

Marco.

[Arkless Electronics]

The LM317 supply line rejection is usually quoted as 80dB (10,000 times reduction) at 100Hz but above approx 500Hz to 1KHz the rejection falls due to a reduction in available negative feedback. With a 10uf Capacitor on the adjustment terminal for noise and ripple reduction the manufacturers of these devices typically quote 70 dB (3,162 times reduction) at 10KHz, 40 dB (100 times reduction) at 100KHz and 20 dB (10 times reduction) at 1MHz. At 10MHz you might as well just wire it out, as it will be serving no useful function. In fact wiring it out will probably be of benefit at 10MHz as the chip circuitry will no longer be in series with the power feed. Another effect caused by this reducing loop gain is a steady rise in output impedance with increasing frequency which, for a given load current change, causes more output voltage variation with increased frequency.

Of course it is relatively easy to design a “super regulator” that exceeds the performance of the LM317, however I would be very surprised if it’s supply line rejection of 120dB (1,000,000 times) could be maintained to 1MHz. As low noise amplifiers typically used for “super regulators” have a similar frequency dependant reduction in available negative feedback to the LM317. Some may achieve a higher open loop –3dB bandwidth than the LM317 but as soon as you reach this –3dB bandwidth limit it is downhill from that point.

So theoretically a 214dB (500,000,000,000 times reduction) would only be valid up to 1 KHz due to the LM317 and the frequency dependant supply line rejection of the “super regulator” would also contribute to the reduction in supply line rejection above it’s -3dB open loop gain roll off point, which may higher or lower than the LM317. This means that supply line rejection will be falling rapidly with increasing frequency.

There is a lot of HF noise on the mains supplies nowadays from a wide variety of sources. The mains earth is rarely an effective RF earth (or even an effective audio frequency earth) and this can reduce the effectiveness of RF filters, and also supply decoupling capacitors, allowing system power line and ground modulation at high frequencies. As typical equipment voltage regulators are becoming less effective dealing with supply line rejection at higher frequencies, supply line noise break through at higher frequencies is a common occurrence and it can break through into signal processing circuits (their supply line rejection is also reducing at high frequencies) causing distortion and inter-modulation with signals.

One reason why a high quality external power supply with extended high frequency supply line rejection can provide a noticeable improvement in sound quality as it provides another wall of rejection to interference. Of course different design solutions used in different items of equipment will vary the result depending on their level of effectiveness. However I sell al lot of external power supplies, for a very wide variety of audio equipment, and I do not get returns due to sound quality issues. If my external power supply upgrade offerings were providing no benefit in sound quality I would be swamped with returns and out of business very quickly.

I totally agree with everything you say from a technical point of view. Obviously the 214dB figure is theoretical and would only approach that at low frequencies but the Super Regulator is still quite effective out to 1MHz and still very effective at 100KHz. RF etc can of course be best dealt with using RLC filtration/CM filters and proper decoupling, grounding and layout practice.
Where we start to differ is as to how much a good external linear PSU can bring to the party. As I've pointed out in previous posts, it can be a whole lot if the unit being powered is pretty naff in terms of it's internal regulation, layout etc. No disagreement there. My point is that when all precautions have been taken in a competently engineered unit with good regulation etc then it doesn't really matter what the external PSU quality is like. There are of course many things that are built on the cheap and/or just badly designed and these will benefit from a quality external linear supply such as the ones you make, BUT in the case of well designed and engineered units which have excellent internal filtration and regulation it will make no difference.... What I'm trying to get across to people is that it is not a universal truth that an external PSU will always make an improvement and nor is it any more true that an even better external supply will make a bigger improvement
There are many applications for PSU's such as yours for things which aren't regulated at all or only very crudely and they will benefit hugely but it is perfectly feasible to make something that is so well sorted internally that nothing more than a wall wart is needed for optimum results.

[Marco]

Jez,


One reason why a high quality external power supply with extended high frequency supply line rejection can provide a noticeable improvement in sound quality as it provides another wall of rejection to interference.

What about the above? Surely if that is true, then it is as good a reason as any to warrant the use of a high-quality (linear) external power supply in applications were one demands the ultimate sonic performance?

The problem you're going to have with supplying any high-end kit with a Wallwart PSU, is the stigma attached to them by your target customers.

Marco.

[Paul Hynes]

Hi Marco,

I guess I will be sending you an external power supply when you test Jez’s phono stage.

Regards
Paul

[Marco]

LOL!

I don't see why not... ;)

Marco.

[Figlet108]

Forgive me if this point has already been addressed, but what about the case of a noisy (SMPS) PSU potentially introducing noise into the rest of the system and being picked up by other components and not necessarily the one it is powering, (which may well have been engineered to ultimate levels of noise immunity)?

I guess what I'm saying is, if we consider the entire hifi as a single complex entity with each PSU in the system as an interconnected component, does that change any of the arguments?

[Markiii]

now thats a good point, and its the same reason I rate within reason decent power leads, not because of the benefit to the power supply to the fitted item, but more because of the reduced interference to everything else

[Arkless Electronics]

Jez,



What about the above? Surely if that is true, then it is as good a reason as any to warrant the use of a high-quality (linear) external power supply in applications were one demands the ultimate sonic performance?


The problem you're going to have with supplying any high-end kit with a Wallwart PSU, is the stigma attached to them by your target customers.

Marco.

It's dealt with already.

Yes the stigma will be the problem. I'll probably be called arrogant for saying this but there are several aspects of hifi where something that is complete bollocks is believed to be absolutely proven to be true by maybe 90% + of audiophiles. This is because they've read it so many times in magazines, been told it by dealers, read it on forums etc again and again and again. They will even often convince themselves that they can hear an improvement because they believe that there must be one if so many have told them to expect one! It's the emperor's new clothes effect :eyebrows: If I know it to be wrong I have no hesitation in saying so and I put my money where my mouth is by building my equipment to my own criterion. The proof of the pudding is in the listening.

I guarantee that any improvement heard with another power supply is purely imagined!

I will even supply an external supply of the highest possible quality for any customer who wants one.... at probably another £300 or so. It won't make any difference though!
Obviously it would be good business for me to say that better PSU's will improve it and to then offer an upgrade path involving increasingly expensive PSU's... maybe at least some will find my integrity and my conviction a breath of fresh air in this FOO ridden pastime of ours.....who knows.... Surely though no one would argue that it's a good idea to make my phono stages less well engineered to the point that an expensive PSU IS required in order to get the best results!!?? :eek:


If one must try an after market PSU be aware that it does not use a standard voltage like 12, 24 etc so you would probably need a custom built one or one that can be adjusted internally.

[Mr. C]

Psycho-Acoustics Jez?

:popcorn:

[Arkless Electronics]

Psycho-Acoustics Jez?

:popcorn:

It happens all the time! Only beneficial for the sound track of Hitchcock films though :D

Approaching :cool: time

[Yomanze]

What a great thread! Very interesting.

[Yomanze]

Psycho-Acoustics Jez?

:popcorn:

I read that as "Psychoacoustic Jazz" just then... only audiophiles can hear it. :D

[Joe]

http://www.youtube.com/watch?v=CbIGwZk8zDI

[Stubies]

spirit of jazz - Far out!

Joe, what are you suggesting? someone has sold their soul to make better equipment? maybe to bend the laws of physics a bit?
:eek:

[Joe]

spirit of jazz - Far out!

Joe, what are you suggesting? someone has sold their soul to make better equipment? maybe to bend the laws of physics a bit?
:eek:

Bend them? This equipment disproves Newton and Einstein, and laughs in the face of Euclid. It can only be obtained by visiting Hell, through one of several entrances, listed at:

http://www.entrances2hell.co.uk/

[Arkless Electronics]

The mighty boosh cannot be over-estimated and has it's own deeper meanings... maybe.:mental: I used to live near Middlesbrough and believe me it's as close to hell as any (in) sane person would want to get! I believe Dante started a new chapter about Middlesbrough but the demons struck him down before he could publish it as it was more than humanity could take... it was a level 42 of hell that went one step beyond your average ghost town :D
OK coats on...

[Arkless Electronics]

PS I like this forum.... you can debate without folks taking it personally and then I have to unleash the hounds to eat peoples first born child unless they buy a phono stage... so messy and ultimately existentially trying :drunk:
:goodnight:

[anthonyTD]

As others have said, its nice to see interesting and insightful discussions like this taking place again here on AOS,
I was beginning to feel that we had lost our way for a while, and was in fear of AOS being seen by some as just an extension of the main stream audio trinket brigade, and glossy mags of old, but then a new face comes onto the scene and stirs up the interest in the true mechanics of things again, its discussions like this that i for one' have dearly missed here, and the reason i came to AOS in the beginning...
The subject of power supplies will i feel' be a long but interesting one, from my point of view, and in my opinion, outboard power supplies can in many cases make a considerable improvement to a lot of kit out there, but mainly because the internal power supplies of the kit in question haven't been properly designed to cope with the tasks expected of them, Paul Hynes is an excellent designer in his field and i have much respect for him, and his products and share a lot of his design philosophy etc,Jez is a new comer here, so i have little experience of his work or products, but i feel there is common ground to be had here regarding all things power related.
Concerning products i have designed and been involved with over the years, i quickly came to the conclusion that for me' to make a truly hi end product, it was of little use to' [using an old term]"close the gate after the horse was gone" in other words, if you design a product from start to Finnish, you have the perfect opportunity to address the issues as you go along, that way, you can end up with a product that is optimized from the start. Yes,like most people in the trade, i had made products earlier on in my career that with hindsight i felt could have been a lot better optimized from the start, but i learn't from my mistakes, and where possible, fixed the issues with those early products at source...
Please forgive me for my long winded ramblings...:lol:
Back to power supplies, if you have free reign to design a product from the start, it is possible to design all aspects of the power supply to be fully optimized without the need for additional add ons, however, when this is not possible,ie; when the product is already out there' then this is where a good and well designed outboard power supply can make the difference...
Anthony,TD...

[bobbasrah]

Spot on Jez and Anthony, excellent posts, a most welcome breath of common sense...

[Cotlake]

Anthony, excellent post. Everything you say on this makes total sense to me :)

[Stubies]

Jez, Paul, Anthony, Marco and everyone - thanks for the great debate - I really have leaned things and have a new appreciation and perspective on the issues!

Terriffic thread!

[sq225917]

it's good to see a technical thread treading the fine line between the sort of positions that have people emptying their wallets for cosmic ray devices and those positions that would people on ZeroGain to sleep. well done all.

[337alant]

Yep agree great thread thanks guys respect ;)

Alan