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chrism
23-01-2010, 11:53
Would like to make a linear 5v regulated supply for a Squeezebox Classic and wondered if anyone has found a low ripple regulated design that does not use standard voltage regulators like the 7810 etc?

Looking for two stage regulator types to give around 1 amp current.

Probably try a 90Va torro and 10,000uf smoothing cap to go with the regulator.

Regards

Chris

Audiocom AV
23-01-2010, 12:03
Would like to make a linear 5v regulated supply for a Squeezebox Classic and wondered if anyone has found a low ripple regulated design that does not use standard voltage regulators like the 7810 etc?

Looking for two stage regulator types to give around 1 amp current.

Probably try a 90Va torro and 10,000uf smoothing cap to go with the regulator.

Regards

Chris

Hi

Paul Hynes Design has some excellent regulators that will deliver 5V @ 1 amp.

http://www.paulhynesdesign.com/

Best Regards,
Mark

Rare Bird
23-01-2010, 13:23
Aye i could do with a bonza 12V Linear PSU for this media player i just bought, get rid of that shitty wall wart PSU

Audiocom AV
23-01-2010, 14:12
Aye i could do with a bonza 12V Linear PSU for this media player i just bought, get rid of that shitty wall wart PSU

Hi Andre

The PHD regulators will also provide a 12V output.

There are also the SR1/SR3 supplies which are ideal for the Squeezebox 3/Classic, etc.

UV101
23-01-2010, 14:21
get rid of that shitty wall wart PSU

LOL! Most definately!

Are you guys into DIY? or are you looking for a finnished product?

Personally i'd build something myself. I'm quite happy to explore the design side here if people are interested?

Puffin
23-01-2010, 14:27
http://www.teddypardo.com/

Power Regs and Teddy Regs.

Try this. More info on Pink Fish Media to build your own.

Arion
23-01-2010, 14:53
For the sum of their parts I'd build my own, or start with a decent linear supply off eBay and adding some capable components.
I hunted for a supply to replace my switch mode 9v job on my Squeezebox Duet and came across the 200 jobs which once you take them apart were nothing very special apart from looking shiny (and no good as mine needs 9volt and not the Classic's 5volt). As I was going to hide mine anyway I didn't see much point in 'pretty'.
eBay gave way to a regulated Sinclair Spectrum 9volt 2amp supply. I took it to bits, IC regulated it to 9volt (it was originally throwing out nearly 12v!) and with a few easy and cheap mods, came up with a beautiful clean linear supply for about 20, a tenth of what some of these supply's cost.
Well done to these guys for making power supply's costing them around 40 in parts (tops) and selling them for a substantial profit to those who know no better than to pay for something just cos it looks the business or someone (usually them) says they're good.

As an interesting sideline, I found a BT MCU250 power conditioner off eBay too (for my amp, not Duet!), neither up to, nor since, have I experienced such an improvement on sound. Apparently this has been a common upgrade for hifi enthusiasts for a while now?

chrism
23-01-2010, 17:06
I would really like to build a ultra low ripple supply that does not rely on any switching type regulation in it.

Ian, I have been researching how to build a two stage regulator (adjustable) but keep on finding ones with the L78XX series regs in.

I was hoping to build a 5v supply and as a second project look how to remove the switching regs out of the digital part of the Squeezebox.

Regards

Chris

leo
23-01-2010, 19:22
I'd second the PHD based supplies, I built a supply for the Duet using his PR3 module http://theartofsound.net/forum/showthread.php?t=3161

I've faffed about with loads of psu's/regulation for the Squeezebox's, dacs etc, for me nothing else could touch this guys stuff

Rare Bird
23-01-2010, 21:13
LOL! Most definately!

Are you guys into DIY? or are you looking for a finnished product?

Personally i'd build something myself. I'm quite happy to explore the design side here if people are interested?

These wall wart hold so much potential back it's beggars belief.

UV101
23-01-2010, 22:18
OK guys, I'd build something. If you search hard enough on eBay, you can find bits'n'pices that will help but not be perfect. Access to a compnent supplier is a must. I use Farnell and RS all the time. They will supply us DIYers but they are trade suppliers merely pushing tin. Do not expect any help in component choice from this type of supplier!

Not sure where we all are technically so i'll start at the beguinning.

We start with 240vac and want to end up with 5 or 12v dc constant, clean and as far as possible free of noise! It must be good vfm and easy to construct!

I would break the task into several area's

Supply treatment (may or may not be required here)
Voltage step down (Good quality torriodal Transformer)
Rectification (Good Quality Diodes)
Smoothing Section (LOW ESR high capacity caps)
Regulation circuit (Many choices here)

Attached is a basic curcuit that would be a massive improvement over the std brick type and could easily be the starting point of some thing much better. Its likely to cost less than 40 to build including a case!

You could expand on the design and use mains filter caps, Hexfred diodes, Mudorf SI caps (very low esr audio grade) and an SPower regulator (good for up to 3A i believe). you could still build this for about 80 and in my opinion would be at least as goos as a commercial PSU costing 3x the price.

Also, check out this eBay link for a basic regulator that is much better than a 78xx type.
LM1084 regulator (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=270487060503&ssPageName=STRK:MEWAX:IT) You'd only need a mains transoformer and you're in business!

Rare Bird
23-01-2010, 22:48
I would really like to build a ultra low ripple supply that does not rely on any switching type regulation in it.

Ian, I have been researching how to build a two stage regulator (adjustable) but keep on finding ones with the L78XX series regs in.

I was hoping to build a 5v supply and as a second project look how to remove the switching regs out of the digital part of the Squeezebox.

Regards

Chris

Chris even the slackest of DIY PSU's will improve on the pieces of shit these wall warts are :lol:

UV101
23-01-2010, 23:49
Like Andre said!!!! lol

I've played a bit more and covered the output voltages mentioned previously.

Included part numbers and costs etc.

See what you think

chrism
24-01-2010, 10:15
Like Andre said!!!! lol

I've played a bit more and covered the output voltages mentioned previously.

Included part numbers and costs etc.

See what you think

Hi Ian,

Looking great. The make or break is going to be the 5v regulator though and it would be nice to find something that we could put together rather than off the shelf. Adjustable from 5v to say 15v would appear to suit most applications but may be impossible.

Previously had a go with the 317 design but could not get it to go as low as 5v.

Regards

Chris

UV101
24-01-2010, 10:37
I've definately had no problems with LM317's on 5v!

I have 5 eBay psu's with integradted 317's in one of my 63's. Each of the boards also drive a 2nd 317 type reg the same as THESE (http://cgi.ebay.co.uk/LM317-DC-In-5-24V-Out-2-5-12V-Volt-Regulator-Converter_W0QQitemZ380200195700QQcmdZViewItemQQptZ UK_BOI_Electrical_Test_Measurement_Equipment_ET?ha sh=item5885b29674).

Thats 5 psu's driving 10 regs all set at 5v! lol

As stated the PSU could be built using eBay 317 type regs for sure. If you then felt the need to improve the regulator (which personally I would) then you can look around. There are many designs around the net. I would suhhest that anything with an opamp in the noise cancellation circuit is going to be good. You also need to ensure that the output device on the board is up to the current requirements.

I have looked at Teddyregs, Tent shunt regs, Audiocom regs and finally SPower regs. I have many Audiocom regs and they are good but in the To-220 style they are not able to drive the load here. Teddy Regs are good and available in kit form (I beleive) but more expensive than SPower and again not in TO-220 format.

In my CD960 which is my main player, I use 9 SPowers a couple of audiocom QPower and a couple of Audiocom Reg2's.

I like the SPower for its size, power capabilities and output quality.

Ideally, we could build something outselves here. There is plenty to research, check out Andrew L Weekes (http://www.alw-audio.co.uk/) if you want to investigate the theory of ultra low noise regs! He also refers to the mighty Walt Jung his site is also of massive interest if you are interested in delveloping a low noise reg.

Its really a question of how far you want to go, an dhow much money you want to spend!

UV101
24-01-2010, 10:42
Previously had a go with the 317 design but could not get it to go as low as 5v.


Hi Chris, just read the start of that last post by me and it sounds a bit condescending. My Appologies for that.

With 317 type regs, they will not give a true reading without load on the output. I tend to set the trimmer as low as possible and and power up with the load connected, measure the op voltage and trim up as necessary.

chrism
24-01-2010, 11:59
Hi Ian,

I don't see anything wrong in your previous post so don't worry about it.

I had trouble with the 317 reg as it was feeding into some kit with it's own internal switching / smoothing regulation system. I could not set 317 to a steady output.

I think that the way ahead might be build the basic supply that you have kindly shown and then test different regulators in it (buy a case big enough to allow this).

I will start getting some bits together.

Regards

leo
24-01-2010, 14:51
Ideally, we could build something outselves here. There is plenty to research, check out Andrew L Weekes (http://www.alw-audio.co.uk/) if you want to investigate the theory of ultra low noise regs! He also refers to the mighty Walt Jung his site is also of massive interest if you are interested in delveloping a low noise reg.

Its really a question of how far you want to go, an dhow much money you want to spend!

One of the psu's I tried with the Duet was the Andy Weekes super regs, first using LM1084 instead of LM317, I then modified it to Teddy reg spec and added a diy darlington
They all worked ok offering an improvement over the supplied plug in smps

http://pic20.picturetrail.com/VOL1293/4634025/12749957/236049804.jpg

Teddy reg mods
http://pic20.picturetrail.com/VOL1293/4634025/12749957/240452421.jpg

Rare Bird
24-01-2010, 16:07
LOL! Most definately!

Are you guys into DIY? or are you looking for a finnished product?

Personally i'd build something myself. I'm quite happy to explore the design side here if people are interested?

O deffo i'd rather build as you can never buy a buy product to your own fussy ideals, i know i can't...I'm not a fan of these dinky little components on modern supplies, i came from a time where massive Transformers, massive Reserviour caps were the thing...

Covenant
25-01-2010, 08:19
Thanks for the ebay link in post 11 Ian. I have sent off for this and hope to build a 15v power supply for my Beresford 7520. :)

chrism
25-01-2010, 19:16
Like the look of the Superteddy regs and are $48.00 on Teddies web site. Can they be bought in the UK?

Regards

Chris

UV101
25-01-2010, 20:02
You got the link? I thought they were a bit more than that!

chrism
26-01-2010, 08:48
Would you believe it, the Superteddyregs have gone up to $59.00 last night! When I was looking yesterday they were only $48.00. Think that I will give that one a miss.

Regards

UV101
26-01-2010, 09:13
If you're at that end of the market checkout those SPowers I mentioned. They are about the same price and in the UK!!

Thats all I use now and they are by far the best I've tried. Admittedly I've not tried Teddyregs but i have read some articles about the design and i'd expect it to be an awesome reg.

I'd stick my Neck on the line and say you'd not be disapointed!

leo
26-01-2010, 09:14
Teddyregs are good for filtering out crap, better than a standard reg, their output impedance isn't ultra low though so sound quality can vary depending what circuit you use them in
Circuits which are constant current tend to be better like the Naim based pre-amps with the TR's, I tried them with the Sabre dac plus a couple of other dacs output stages and found they made the sound over soft and coloured for my taste
Of course opinions vary;)

UV101
26-01-2010, 09:21
Teddyregs are good for filtering out crap, better than a standard reg, their output impedance isn't ultra low though so sound quality can vary depending what circuit you use them in
Circuits which are constant current tend to be better like the Naim based pre-amps with the TR's, I tried them with the Sabre dac plus a couple of other dacs output stages and found they made the sound over soft and coloured for my taste
Of course opinions vary;)

I'm interested in the theory here. Does this mean that they would not be ideally suited to a dedicated application inside a cdp for example? I have 3 regs on my TDA1541 (+5,-5 &-15v) How does the fact that there is not a measured constant load effect the device?

chrism
26-01-2010, 09:23
Hi Leo,

Was thinking of a constant current design for the Squeezebox as it looks easier to make and can always be swapped out later.

For the Beresford Caiman I was thinking of tracking regulator type supplies (like Avondales?), one at 5v and one at 12v. These would then feed into the DAC and allow the removal of the voltage regs.

Regards

leo
26-01-2010, 10:23
I'm interested in the theory here. Does this mean that they would not be ideally suited to a dedicated application inside a cdp for example? I have 3 regs on my TDA1541 (+5,-5 &-15v) How does the fact that there is not a measured constant load effect the device?

Output impedance of the Teddy regs varies with the current drawn , with a circuit like the older Naim pre -amps the TR's see a constant current on the output so its not really an issue, things like op-amps etc don't act as a constant current.
I prefer regulators with the lowest output impedance over the widest bandwidth, things like shunt regs and jung types

Like you I've also now found my preferred regulator type so tend to stick with that, I've tried a lot of regulators in lots of applications, best way is to just try as many things as possible.
Things like the Teddy regs can be built on bits of vero board so easily tried out, you may like them (alot do) . Some regs using high speed error amps are more tricky to build and can suffer instability on vero

leo
26-01-2010, 10:28
BTW the Swenson regs work pretty well for the TDA1541A's +/-5v , they can be adjusted for higher voltages but require strings of leds, the ALW's work well on the -15v

The Swenson circuit can be found online, their pretty easy to build, I used one in the Beresford dac with pretty good results, not suited for higher current apps though

leo
26-01-2010, 10:38
Hi Leo,

Was thinking of a constant current design for the Squeezebox as it looks easier to make and can always be swapped out later.

For the Beresford Caiman I was thinking of tracking regulator type supplies (like Avondales?), one at 5v and one at 12v. These would then feed into the DAC and allow the removal of the voltage regs.

Regards

Remember that the Squeezebox can be quite a load for some regs so just be sure the design used can handle it without over heating

The tracking regs are pretty decent and cheap as long as they have the voltage headroom to allow for the needed drop out, should be fine for the 5v section, not sure about the 12v analogue though if using the external 15v main supply

chrism
26-01-2010, 10:47
Hi Leo,

I have a 1.2A rated cheapo linear on the SB at the moment and it gets a little warm so yes will probably need over 1.5A.

I am hoping to build a new linear PS (I already have a simple linear supplying 15v) for the Caiman with two separate supplies, one at max 5v and one at max 12v (each with a tracking regulator). The supplies are to have their own smoothing and I am proposing to connect to the position where the existing voltage regs were.

Regards

Chris

here we go again
26-01-2010, 13:19
I am hoping to build a new linear PS (I already have a simple linear supplying 15v) for the Caiman with two separate supplies, one at max 5v and one at max 12v (each with a tracking regulator). The supplies are to have their own smoothing and I am proposing to connect to the position where the existing voltage regs were.

Regards

Chris

Chris - be aware that the Caiman also uses the 'raw' 15v from the external switching psu - the headphone op-amp is supplied from it - other bits on the front board may do too - I didn't follow it any further. So you're gonna need 3 seperate supplies in order to keep the Caiman working as advertised.

sorry, we seem to have briefly meandered off the original topic folks!

chrism
26-01-2010, 16:37
Hi Graeme,

Thanks for the nudge about the Caiman and I noticed you have already been doing a lot of power supply mods on it already.

I will stick with the Squeezebox for now and have a better look at the Caiman once I have made the simpler one.

For the Caiman, the voltage at the input cap is less than 15v as the diode at the front reduces by 0.7v. I feed in at 15.2v so the cap only sees about 14.5v.

On this basis it looks like a constant load regulator feeding 15.2v as normal to pick up the "other stuff" would be best. Then low ripple tracking regs fed into the 12v and 5v voltage regs positions. So three separate supplies all at differing voltages. May be best with 3 small toros due to the 5v requirement.

Regards

Mike
26-01-2010, 20:57
While we're talking about reg's...

Anyone have any thoughts on improvements here?:


http://img403.imageshack.us/img403/3019/phono1.jpg


At the moment the bridge diodes are Vishay 95SQ015 and the reg is a LM1085IT LDO type..

Cheers...

Audiocom AV
26-01-2010, 23:55
While we're talking about reg's...

Anyone have any thoughts on improvements here?:



Hi Mike

There are a number of low noise regulator designs that will improve the LT1085, most series regulators or shunt will require heavy heat sinking to deliver 2A. For the 4700uf reservoir I have found the Jensen 4-pole to the best of the all. You could try the HexFRED diodes from International Rectifier instead of the 95SQ015 Schottky. For the regulator bypass use try a Silmic RFS, Black Gate FK, Panasonic FC.

Regards,
Mark

Mike
27-01-2010, 00:15
Thanks Mark,

Thinking about it, I think I made a few changes after that. IIRC there are two 4700uF caps and a low-R / high-W resistor forming a Pi filter, and I think there's another resistor to burn off a few volts before the reg too. All the caps are Panansonic something or other, I'll have to open it up and refresh my memory. :scratch:

Cheers...

UV101
27-01-2010, 22:04
Hexfreds are indeed good and all I use these days. In my earlier post with the diagram http://theartofsound.net/forum/showpost.php?p=96778&postcount=13 I've included Hexfred and Panasonic TSUP caps. These caps are excellent VFM but there are better lower ESR about. I like Mundorf MLytics but that are no longer in production. I believe they were made by F&T caps in Germany. BHC also make some high uF low esr audio grade caps.

Bigger resevoir caps pre reg are usually a good thing. I use up to about 22000uF even on low current applications! I'd poss try a 10000uF here. Post reg i never use Panasonic FC. BG's are ace but getting harder to find and pretty expensive. Elna Silmic II's could be good and Nichicon make some OK caps. I wouldn't use Rubycon ZA or OsCon here (they are both good on digital rails).

Capacitor choice is a bit of a personal thing tbh! If you've tried something and you like it, stick with it!

As for the heater regulator. You should be able to adjust any suitably rated low noise reg for 6.3v no problem although I've never used a low noise reg for tube heaters before! I keep mentioning them but I like SPowers and they will def deliver the current required here!

I really like the 2 transformers! Stepping down for the low voltage supply and back up again will decouple the highvoltage side from the mains! I've looked at this type of isolation in mains conditioning but the size of the tx's i'd want mean i need to think about it a bit more!!lol

I'd also poss put a couple of suitable rated self healing MKP caps Y2 maybe 10uF L-N (not forgrtting a discharge resistor)and 0.022uF L-E and N-E to clean the mains of any unwanted pops and crackles but only of you are comfortable in this area! :cool:

ar-t
29-01-2010, 22:38
I just finished making one for a private customer. It draws 0.82 A. So, yes, it does get warm. I am running it at 5.6 V, for reasons that probably are not germane.

Despite having a very low output impedance, you can still see current modulation on the output. Sodding Wi-Fi card.

To get around this problem, I added a separate PSU just for the SPDIF/clock circuitry. Trying to measure the noise on that rail is a small challenge, as there is so much radiation from the Wi-Fi card that it shows up on the measurements.

My understanding of the SB2/3 is that it goes through a step-up converter for the display. All other voltages are step-down converted from that supply. So, not sure how much noise rejection is needed for the "non-critical" circuitry, since there are 2 stages of DC-DC conversion. There is an over-voltage limit on the input, in case you stick something like 9 V into it. It will not start. Not sure if there a under-voltage limit, as my regulated lab-style supply can only deliver 1 A. It strains trying to power one.

The stock SMPS has mains frequency spikes out to...........well, more than one might hope. In addition, there are nasty sidebands all every one of them. Part of that might be an artifact of using a sampling analyser

chrism
30-01-2010, 10:20
The main issue for the SB power supply does appear to find a super quite regulator that can allow up to say 1.5 - 2 A peak current demand without getting "hot".

Anyone know were you can by a ready made full wave rectifier that will allow 9v AC in and say 12v DC out? I am not wanting to use Veroboard and am proposing to bolt / screw down each bit onto a steel tray (using Ian's design as a basis though).

I am also struggling to find a really good trafo (encapsulated if poss) rated at say 30Va to give 9-10V AC.

Regards

Chris

UV101
30-01-2010, 13:17
Hi Chris - PM'd you too!


The main issue for the SB power supply does appear to find a super quite regulator that can allow up to say 1.5 - 2 A peak current demand without getting "hot".

Any regulator pushing that amount of current will need a heatsink and it will get hot! There are a few commercial low noise designs that can do it tho'.


Anyone know were you can by a ready made full wave rectifier that will allow 9v AC in and say 12v DC out?

The rectifiers wont change the voltage (per say) just change ac to dc. If you want the exact science, I'm pretty sure that you'll end up with 1.4 times more volts on the dc side than the ac! If you are looking for multiple rails. You sepc the 2ndary winding to give you maybe 5v higher than the highest voltage rail you need. Then off to the regulator(s) to do thier bit.


I am not wanting to use Veroboard and am proposing to bolt / screw down each bit onto a steel tray (using Ian's design as a basis though).

In a previous post, it was mentioned that there are some very well made PSU pcb's designed accept rectifiers, smoothing cap and regulator. They just need low voltage ac in and give you the regulated dc out (also need a heat sink for that current as mentioned before!)


I am also struggling to find a really good trafo (encapsulated if poss) rated at say 30Va to give 9-10V AC.

Personally I prefer open torroids at this VA because they are smaller! You will need to mount this all inside a case anyway. Look at RS or Farnell for these suitable 9v tx here from RS (http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=2237816)

I think that covers it for now!!!:cool:

UV101
12-02-2010, 23:48
Just to update....

I'm going to build Chris a 5v PSU for his squeezebox. I've ordered some of the the bits today and will document the build on a new thread.

Needless to say, I have very high hopes for this PSU.

The components (Audioupgrades PSU PCB, Transformer, Hexfred diodes, TSUP capacitor and case) should be here on Monday and Tuesday. I'll post photos and document the build during the course of next week!

:cool:

leo
13-02-2010, 00:38
What reg are you going to use? S-power?

UV101
13-02-2010, 07:53
What reg are you going to use? S-power?

How did you guess????;)

We'll be using the PSU board version as opposed to the TO-220 (std 3 pin regulator). I've ordered a board with SPower only, no cap,tx or diodes. Although the output fet can deliver the current, i'm expecting to need to upgrade the heatsink.

http://www.audioupgrades.co.uk/psu.shtml

chrism
13-02-2010, 09:23
Thanks Ian,

Yes not really sure if it will actually improve the SB but for the cost willing to give it ago. It may be that the internal switching regs also need to be removed to gain the benefit of a linear supply - we will see.

Went with Ian's suggestion of the S-power as it is already built on the PSU board and looks very tidy.

Regards

Chris

leo
13-02-2010, 10:10
Should be well worth the effort, I heard an improvement with analogue out and also spdif out feeding the external dac after upgrading to the Paul Hynes PR3 , those stock SMPS are shite tbh

Anyway keep us updated:)

UV101
15-02-2010, 15:24
OK Guys, I've started a new thread here to document the build of a 5v supply for chris

http://theartofsound.net/forum/showthread.php?t=5463