Why ' what's wrong with your HE psu ?
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Why ' what's wrong with your HE psu ?
The HE should be pretty good, although of course I haven't done a direct comparison between the two....
Andrew, if you're curious, we could swap PSUs for a week - that way we'll both be able to assess which one we think is best, and if the SR5 isn't as good as the HE (which I doubt), you won't have wasted any money :cool:
Marco.
I'm genuinely surprised there's such a difference in these supplies, unless it's the noise behaviour getting back into the cartridge in some way, or possibly the very "fast" quartz servos or summat :scratch:
That PH supply has a hige transformer in it that I reckon would do a mid priced integrated amp good service :)
Indeed - and that's precisely what's lacking in the HE ;)
Experience tells me that hugely 'over-specced' T/T PSUs, using massive mains transformers (for the job), often sonically outperform other PSUs which don't use such large mains transformers - why, I'm not sure, as I believe technically it *shouldn't* make a difference once one achieves 'the ideal' in an electrical sense.
However, I'm sure that Paul could provide a credible technical argument for why having such a huge mains transformer inside a T/T PSU is sonically beneficial. Lower noise, perhaps? Paul, what's you're take on it? :)
The theory that suggests it shouldn't make any difference was blown out the water, however, around 2004 when I swapped the (then) Linn Lingo on my LP12 for a Norton Airpower, which used a massive mains transformer, similar to the one Paul has in the SR5, and the improvement the Airpower brought over the Lingo (and an Armageddon I tried at the same time) wasn't subtle!! :eek:
I don't believe that there was anything particularly 'fancy', component-wise, inside the Norton - its design principles were mainly based around its huge mains transformer.
It's yet another example where measurements alone (at lease those normally used in these applications) don't always tell the full story.....
Marco.
Marco, if you recall, I once walked into a spat with Dave Cawley over aspects of PSU design that I don't fully understand, but which Paul Hynes does! He does explain the principles on his website. Clearly a big toroid helps, but fundamental design helps even more!
My feeling about the Technics and why it responds so well to PSU magic, is that it probably presents a rather complex load, which translates into the need for a very fast and very wide bandwidth PSU. Clearly some PSU designs are better than others;)
Maybe we're not looking finely enough at instant temporal responses to needed current (I can't explain it properly but hope you get the idea).
One thing Naim really did do was to re-introduce the over-supply idea, especially on their preamps. I know this is only a tiny part of the picture, but having a high capacity reservoir in both transformer and storage caps may count more than otherwise thought - I wish I'd been better at advanced maths, as I could have been an electronics engineer and able to work it all out. PLEASE Mr Hynes, help me out here.....:)
This might help explain things or might raise more questions :eyebrows:
All an amplifier is basically boils down to it being a power supply that supplies AC voltage to a load. Now those that have experienced class A amplification tend to want to stick with it, this is because all the current that the load will ever require is already there at the output stage. It never needs to turn on any harder unless it goes into class B with some ridiculous load. This should make the amplifier pretty fast & low distortion...
What you have with the SR5 is basically a class A power supply :) It's shunt rather than series regulated & this means that all the power that the turntable doesn't use is being dissipated by the shunt transistor or mosfet (probably a lateral mosfet from what i have been reading). To increase the load currennt the shunt mosfet actually needs to turn off some rather than on. Again it can react very fast indeed just like a class A amp & it should have a much lower output impedance as a consequence ;)
A series regulator is like a class B amp in that it needs to turn on harder to supply more current & this takes time so it's slower, though more efficient.
The reason the transformer is large is due to the class A type of operation where all the power would need to be dissipated by the PSU itself with no load connected. As well it being sensible to use a big transformer for best performance.
You want a car to go fast & accelerate like the clappers then fit a dirty great big V10 engine. If you are happy to chug along, accelerate slowly & slow down going up a hill (when the going gets tough) then fit a 1L four cylinder jobby :eyebrows:
18:48 E2A:- Just been looking at the pictures of the interior of the SR5 :scratch: I might be mistaken but it looks like a series regulator to me, i can't see a dirty great big aluminium clad wirewound resistor that would be needed as a series component to dissipate power :scratch: Besides that there is no where near enough heatsinking for a shunt regulator :eyebrows:
Hi MarcoQuote:
Originally Posted by Marco
Back in the day when i had an LP12 ! i just got the Lingo , but then i noticed all these other psu's available ' i talked to my Linn dealer and this is what he said ' please ' please don't go near any of these dogdy ' possibly illegal aftermarket rubbish psu's they will ruin your LP12 , err yeah ok :scratch:.
I think this kind thing still go's on but is one of the reason's i moved the LP12 on , but not the main reason of course .
Marco,Quote:
Originally Posted by Marco
Now that seems like an offer too good to refuse :stalks::stalks: Let's wait till after Xmas, I need to fine tune the Mike New bearing/stiffning plate/Cu composite platter and SME V before I let the Timestep go. I've only just got the whole thing set up and working so I want to listen to some vinyl before I embark on another batch of upgrades. How does back end of January sound??
Andrew, how did you find the base plate installation? I wrote it up elsewhere, not sure if you saw that.Quote:
Originally Posted by REXTON
Hi Andrew,
Sounds good to me, matey - that's a plan, then! :)Quote:
Now that seems like an offer too good to refuse. Let's wait till after Xmas, I need to fine tune the Mike New bearing/stiffning plate/Cu composite platter and SME V before I let the Timestep go. I've only just got the whole thing set up and working so I want to listen to some vinyl before I embark on another batch of upgrades. How does back end of January sound??
I've been dying to compare the Timestep HE to the SR5, so now's my chance. Full review on their various merits to follow... :cool:
Btw, I've just taken a few new shots of the Techie - this time off of the rack, after fitting the new Oyaide PA-2075 DR tonearm cable to the Jelco:
http://img576.imageshack.us/img576/9136/img0172e.jpg
http://img820.imageshack.us/img820/5949/img0175s.jpg
http://img530.imageshack.us/img530/5163/img0174o.jpg
http://img59.imageshack.us/img59/4222/img0177k.jpg
:cool:
Marco.
Looking good Marco, looking good.
Churz, matey... Off for a listen, now! :gig:
Marco.
Just looking at Paul's PSU and being interested in the mains supply for obvious reasons, couldn't help wondering what effect this would have on the performance?
http://i622.photobucket.com/albums/t...-1501R-300.jpg
Basically a mains filter/iec inlet. Not suggesting anyone takes Paul's unit apart and fits their own, maybe Paul would like to try one out and offer it as an up-grade if it does the job?
In my case, no need as my SR5 is being fed ultra-pure mains from my PS Audio Powerplant Premier regenerator.
Is that the one that uses USA power plugs mate?Quote:
Originally Posted by MartinT
It will be interesting to know what you think about it in comparison with the Neglex cable. I was very surprised at how much better Audio Origami's tonearm cable was over the Neglex, which looks nice but is a bit average sounding. Methinks you are about to remove a musical bottleneck!Quote:
Originally Posted by Marco
I'd definately say that it'd be much cleaner & lower distortion than via a simple mains filter, that's for sure ;) The Premier reduces distortion by a factor of 10 from what i have read which is significant, but i wouldn't call it ultra-pure by any stretch of the imagination :cool:Quote:
Originally Posted by MartinT
Still, 0.25% is better than 2.5% & a very worthwhile improvement :eyebrows:
Having said that i wouldn't dismiss a mains filter as most of the distortion on the output of the Premier is likely to be high order & high frequency ;) It is effectively only an amplifier at the end of the day & feedback reduces with increased frequency meaning distortion increases :rolleyes: These kind of filters are not effective at low frequency but increase in effectiveness as frequency increases....
No, I have a proper UK spec model with IEC (Euro) input and five UK 13A sockets, one for each isolation zone.Quote:
Originally Posted by Mains Cables R Us
It depends on what you're comparing it with. A filter won't be able to reconstruct the straight-sided sinewave distortion that occurs when thousands of Sun readers put the kettle on before Eastenders, but the PPP can and does. Also, it's not just about purity of sinewave but broad spectrum noise filtering before the amplifier stage, thus preserving low output impedance. And as I think we've discussed before, it's a rather clever tracking amplifier that sits 'on top' of the mains waveform and applies correction, unlike its enormously heat dissipating predecessors. So no heat, little noise and no fans whirring.Quote:
Originally Posted by Reid Malenfant
I take what you say - distortion is reduced not eliminated - but the proof is in the listening and I've yet to hear a system that is not improved with a PPP.
Season’s Greetings to all the AoS members, especially those who have been so supportive over the last few years.
Hi Marko,
I am no transformer specialist and the information I give here is based on discussions with specialists when I have been looking for exceptional performance for my projects. In particular Terry Monaghan from Canterbury Windings has been very helpful in my quest for a very high performance transformer for the SR5. Terry has been in the industry for a long time and specialises in Audio Grade transformers. His products are excellent.
You are right about size matters however there is a lot more to the SR5 power transformer than being oversize for the job.
Firstly, all the ‘off the shelf’ transformer ranges you can find in the component catalogues are built to a price in a very competitive market, primarily for industrial use. They are usually wound with a high flux density for efficiency. If you switch them on when the mains voltage is high they can easily go into core saturation and can take a long time to recover from this. The materials used in the construction are, to be kind, ‘cheap and cheerless’. They are wound on automatic machines with little care and attention to detail during the winding process. They are running on the edge all the time because of these manufacturing conditions. Most of these transformers are very noisy mechanically as they often have loose cores and windings. This type of transformer has no place in a high-end system, where background noise can be a serious distraction, so what I am about to say does not relate to these low quality transformers.
Regarding the size issue, back to my family saloon/Bugatti Veyron analogy. Both will take you where you want to go but the Veyron will do it effortlessly. Put your foot down and the family saloon will struggle but will get you there eventually. Trying to stop rapidly is also a struggle. The Veyron will go like a bat out of hell and stop on a sixpence. It’s just coasting with far more energy available and a heavily engineered system to keep things under control when the going gets tough. Yes it is over-specified for the job, but I know which I would prefer, and it is not just about looks and flash. The performance is exemplary.
Increasing the transformer size allows for reduced secondary impedance, which in turn allows more current to be available for transient demands. The flux density in the primary drops with increasing size and this reduces the sensitivity to core saturation overload. There is also less leakage flux from winding to winding, which reduces interaction between the windings. The winding technique is critical to high performance and this is an area where information is carefully guarded due to proprietary rights protection.
The SR5 transformer is one of Terry’s specials. The winding is carefully controlled on a manually operated winding machine. High quality materials are used and the transformer is wound on an oversize core with inherently low flux density so there are no core saturation problems even when the mains voltage is higher than usual. The transformer is designed for silent running so no annoying buzzes in the listening room.
The transformer combined with the regulator module I use for this supply gives an exceptionally quiet power supply both electrically and mechanically.
Hi John,
‘Interesting Power supply Paul.
Do you have a spec sheet and price for it?
Is that phosphor bronze?’
The regulator is a proprietary discrete component topology using error amplifier devices with a noise spec of 0.5 nanovolts root Hz and a noise corner of 1 Hz. The regulator output noise measured 35 nanovolts root Hz on an HP3561a spectrum analyser. This is half the noise level (6 dB lower) of the low noise version of the ALW regulator that many audio enthusiasts have used in their DIY projects. 35 nanovolts root Hz is around 5 nanovolts rms over a 20 KHz bandwidth. A National Semiconductor LM317 would typically have around 630 nanovolts rms output noise in standard configuration and in the region of 63 nanovolts rms output noise with the low noise configuration when set for an output voltage of 21 volts.
Cascode operation of the SR5 regulator error amplifier, on a higher supply rail than the output stage, extends the bandwidth out to around 400 Mhz allowing high-speed drive to the mosfet output device gate, which in turn enables rapid, very high transient current delivery, into the load.
The output mosfet is a very rugged IXYS device capable of delivering large transient currents, well in excess of 60 amps, into the load. The continuous current delivery is 4 amps. Both of these current delivery specs comfortably exceed the SL1200/SL1210 requirements with Mike New’s excellent Platter and bearing system fitted to the deck.
Output impedance of the regulator measured <3 milliohms from DC to 80 KHz and the supply line rejection >80 dB from DC to 80 KHz.
The output Mosfet is mounted on a copper bracket to enable fast heat removal under high current conditions.
Mark,
The SR5 is a high-speed series regulated power supply not a shunt regulated one. I have a high current shunt regulator design that would work with the SL1200/SL1210 but it is not as quiet as the series regulator (around 12 dB higher noise level). Also the available transient current is restricted to the current limit setting of the current source feeding the shunt element of the regulator. This regulator requires heavy thermal engineering and is more costly to implement.
I have to go now, as food is ready (and wine I hope).
Regards
Paul
Yep, just sussed that out at about 18:48 by looking at the pictures you kindly linked to :eyebrows: I didn't think there was enough heatsinking & i couldn't see a series dissipating element such as a power resistor or possibly another mosfet used as a resistor ;)Quote:
Originally Posted by Paul Hynes
Hi Mark,
It's not necessarily what you use. How you use it can be significant.
Have a good Christmas and I hope the New Year is a good one for you.
Regards
Paul
Thanks for that excellent circuit description, Paul. I didn't think it was a shunt regulator as I ran it at work all day on zero-load soak and there was no heat!
High power shunt regulators eat power and are relatively expensive to run. This is relevant with electricity costs spiralling ever upwards :stalks:, although just like a class A amplifier, you can use them for background heating as well as powering equipment.
One thing I did not mention in my last post regarding power connection from the SR5 to the SL1200/1210. I am not particularly pleased with the performance of the DC connectors used in much consumer electronics nowadays. They are really designed for low cost equipment and their contact resistance and reliability can be questionable. Even the ones using a screw-locking collar do not inspire me with confidence with regards to providing a reliable long-term low impedance connection.
I have fitted a 2.5mm DC connector in parallel with the SR5 XLR DC output connector for some of you, who for convenience, wanted to use the Timestep DC lead already fitted to your deck. For reliability and better sound quality I recommend using the XLR DC outlet on the back of the SR5, rather than the 2.5mm DC connector, as the XLR is a much better connector with a contact resistance spec of <3 milliohms. The pin configuration for the XLR on the back panel is pin 1 = 0v and pin 4 = +21v. If you decide to make yourself a new DC lead, use quality wire with a decent current rating and preferably use a high quality XLR plug as the low cost ones have questionable performance. Also make sure you get the polarity of the power correct as you will do damage to the SL deck electronics if you do not. You should hear a worthwhile improvement with a high quality cable/XLR lead replacement. For even lower impedance I can fit a Jeager industrial precision connector to the SR5 as a custom option, which specs at <1 milliohm contact resistance.
Regards
Paul
Thanks, Paul. Any idea where I can source a 4-pin XLR plug, as they seem rare compared with 3-pin?
Scratch that, found Neutrik connectors at CPC.
Hi Martin,
I use Deltron silver plated connectors from Farnell. Neutrik are another good make.
Regards
Paul
Hi Paul,
I've been rather busy and will contribute more to this thread later, but regarding this:
How would you know what is correct or incorrect in that respect? Anthony will likely be doing the job for me :)Quote:
Also make sure you get the polarity of the power correct as you will do damage to the SL deck electronics if you do not.
The reason I ask is that I've obtained a high-quality DC cable from Kimber which I'd like to fit to my 1210.
I'd also like to fit it to the XLR plug you supplied with the adaptors you made up to take a 2.5mm DC connector, so that the end of the adaptor (with the XLR plug) goes into the SR5, presuming that the XLR plug you used is of decent quality for the job I have in mind?
Therefore, your advice on this would be appreciated :cool:
Marco.
Hi Marco,
The power supply 0 volt terminal (pin 1) would be wired to the ground point on the control printed circuit board at the same point the timestep lead 0 volt wire is connected, and the +21 volt terminal (pin4) would be wired to the same point that the Timestep +ve wire is connected to the board.
Anthony will know what to do.
For others who are competent wiremen Shuggie has posted about this in
http://theartofsound.net/forum/showthread.php?t=8118
For those that are not confident with internal modifications seek help from someone who has good diy abilities or find a good pro electronics engineer who can do it for you. You can also ship the deck to me for modification if this is your preference although I will charge for my time, as would any other engineer.
It’s not a difficult mod, you just have to pay attention to what you are doing and check your work thoroughly before applying power.
For those wishing to implement the internal dual regulated modification, details will be posted shortly.
Regards
Paul
Hi Paul,
Thanks for that - sounds straightforward enough :)
Marco.
Marco, if you keep the 2.5mm connector in circuit you're not going to benefit much by use of the Kimber cable. You need to solder the cable to the Technics PCB and the XLR plug to the other end, eliminating the 2.5mm connections altogether. I will be doing the same as soon as I receive the Neutrik plug.Quote:
Originally Posted by Marco
Hi Martin,
Sorry if I didn't make myself clear - that's exactly what I intend to do :)
Which DC cable are you going to use, or did Paul provide something suitable along with the SR5?
I'm still using the original cable supplied with my old Timestep PSU, as that's what was already soldered into position. It's a bit too thin, though, and not of particularly great quality, which is why I'm going to use the Kimber DC cable supplied with the Russ Andrews 'Dynapak' PSUs. I obtained some of this cable, as a special order, a while ago.
It's the same as shown here, fitted to the Russ Andrews Dynapak DC PSU (the cable is the usual Kimber RFI-rejecting 'woven' design - like a thinner version of the stuff used in their Classic Powerkords):
http://img831.imageshack.us/img831/2255/1801l.jpg
I was using it when I had my old KAB PSU (where it was a big upgrade on the usual supplied 'black & white' DC cable), but Dave C didn't want to retain it when he fitted the Timestep, as he said it was, I quote: "an unknown quantity"....
Anyway, one end will be hard-wired to the Techie's PCB, and the other fitted with an XLR plug, to go into the back of the SR5. That should give a further sonic improvement :cool:
Marco.
I have been following this thread with interest as I have an SR5 on order.
Perhaps someone could explain please what is the dual regulated mod as mentioned by Paul.
Hello Paul,
The dual regulation mod is the next level of power supply upgrade for the SL1200/1210 after the installation of the SR5. It is an internal modification of the SL1200/1210 printed circuit board and installation of two additional voltage regulators. It consists of separating the power feed to the control circuitry and the motor drive circuitry and providing each with a separate high performance voltage regulator.
Separating the regulation for the control circuitry and the motor drive circuitry reduces interaction between these stages, via the power line on the internal printed circuit board, and this also improves the sound quality of the deck giving a more open and stable sound stage with improved dynamic scale.
The external SR5 power supply is then adjusted to 27 volts to provide pre-regulation of the two internal regulators, effectively providing two layers of supply line interference rejection and making the deck much less susceptible to performance variations caused by varying mains quality.
Aside from the above improvements there is also a nice improvement in low-level information retrieval with these modifications.
This level of power supply upgrade requires reasonable DIY experience, as some printed circuit track surgery is required as well as wiring in the two additional voltage regulators. For those who do not wish to implement this modification themselves I will be offering this upgrade as a service in the New Year once the holidays are over.
Regards
Paul
Thanks Paul for the explanation. I will be in touch after Christmas.Quote:
Originally Posted by Paul Hynes
Is all this in addition to Dave C's regulator mod, or instead of? Dave has provided measurements showing the difference his regulator mod made and it was quite extensive. if this is done, would a double reg really make things any better or just introduce more complexity?
I'm not sure but you may recall Dave that i mentioned this on another thread ;)
I brought up the fact that in effect the voltage regulation wasn't taking place where it was actually needed, but at the power supply itself. What's needed to get the very best out of the 1210 is a quality regulator that controls the voltage right at the 1210 PCB, rather than up to 1M away with all the fluctuations that current draw over the cable resistance will cause :)
At that point Paul joined in the thread & mentioned he was working on a couple of regulators that will each be in control of one part of the TT systems. Splitting the contol circuits (which use little current & much more uniform current draw) from the motor power circuits that will draw current in big pulses makes perfect sense.
You may think of it as more complex, but in reality it's far harder to regulate a supply that has big current fluctuations. Splitting it will bring pretty big benefits as well as having the regulation exactly where it's needed & not at a distance. In certain respects making things a tad more complex makes things a lot easier & will definately improve things ;)
Paul,Quote:
Originally Posted by Paul Hynes
I'm going to be borrowing Marco's SR5 next month at some point so I cant wait to see your handywork! I have a few questions. Firstly, will you be publishing or supplying relevant kit for this mod so us "tweakers" can have a crack at installing it. Secondly, how many levels of voltage regulation could be added to the 12xx series and would we start getting the laws of diminishing returns with regards to the number of levels of regulation regards information detail?? I'm thinking of some threads I've been reading about CD modifications where there seems be voltage regulation for every circuit on the PCB!!
I'm liking the sound of that! I therefore can't wait to have my T/T's PSU configured that way - this is going to be MEGA!! :eek: :eyebrows:Quote:
I'm not sure but you may recall Dave that i mentioned this on another thread ;)
I brought up the fact that in effect the voltage regulation wasn't taking place where it was actually needed, but at the power supply itself. What's needed to get the very best out of the 1210 is a quality regulator that controls the voltage right at the 1210 PCB, rather than up to 1M away with all the fluctuations that current draw over the cable resistance will cause :)
At that point Paul joined in the thread & mentioned he was working on a couple of regulators that will each be in control of one part of the TT systems. Splitting the contol circuits (which use little current & much more uniform current draw) from the motor power circuits that will draw current in big pulses makes perfect sense.
You may think of it as more complex, but in reality it's far harder to regulate a supply that has big current fluctuations. Splitting it will bring pretty big benefits as well as having the regulation exactly where it's needed & not at a distance. In certain respects making things a tad more complex makes things a lot easier & will definately improve things ;)
Paul, is that what Anthony and you have been working on, and if so, will he have all the bits necessary to do the job (and be aware of what's involved)? :cool:
Marco.
Here you go :eyebrows:
hi all,
the new techie mods paul is offering at the moment are his own designs, however, we both agreed in our descusions that individualy regulating certain parts of the techie circuitry would be very beneficial.
as a help to paul, i will probably be offering my services to the less technicaly minded who would like these mods carried out in the new year, however, this would need to be discussed between paul and myself before we can proceed with a plan!
Anthony,TD...
Thanks for the clarification, matey :)
Marco.
Well that dual internal regulator mod really looks intriguing.
Would love to hear impressions with SR5, pre and post internal regs, on a deck equipped with a MN bearing and platter.
Hi Pete,
Don't worry, I'll be doing precisely that in due course... I expect this to be *the* definitive off-board PSU solution for the SL-1200/1210 which will leave all others in the shade! :)
Marco.
Well life just doesn't get much better than this :)Quote:
Originally Posted by Marco
Merry Christmas to all and to all a :goodnight:
Marco and Paul
Be careful about using the same point as that used by the Timestep PS.Quote:
Originally Posted by Paul Hynes
I have a customer in Melbourne who received his new 'modded SL1200' with the zero volt wire connected to the top of the PCB under one of the self tap screws, for convenience presumedly. Fortunateley he is a former Hewlett Packard instumentation engineer of some considerable experience, he called me to indicate his dissapointment at this.
These screws should not be use as the earth point, as they have no connection with the zero volt copper track on the PCB. The only screw that serves as the earth connection point on the PCB is the bottom left hand corner, where the copper track is taken specifically to this point.
If any other earth point is used, then the 0 volt circuit will be via the alluminium chassis. The die cast alluminium is to an extent granular and is certainly not a good conductor, thus you will have a resistance (and noise) to earth which could seriously degrade performance.
Marco...
The reason I ask is that I've obtained a high-quality DC cable from Kimber which I'd like to fit to my 1210.
Would that be the kimber cable that uses copper that has been specially optimized for mains voltage, their phrase not mine???
Hi Mike,
Noted - cheers! :)
Hi David,
Dunno, mate - it's just their ordinary DC cable, as far as I know. But it works very well!
How's the Techie sounding, then? :cool:
Marco.
I used the screw on the bottom left , a metal tag/washer on the top board goes through the pcb and is in direct contact with the main ground on the bottom of the pcb . I'd be surprised if TS did use one of the other screws :doh:Quote:
Originally Posted by Mike_New