Chinese Linear low power/noise - quality?

[bugbear]

I want a high quality PSU to drive the analog stage of a HiFiBerry DAC+ Pro.

I am considering Chinese/eBay models, which come all assembled, cased etc for amazingly little money.

Makers/Brands/Sellers include

Jays Audio
Breeze
Talema
Zero Zone
Teradak

e.g. eBay item 112043512540, £43.000 delivered.

I would like to be able to alter the PSU (if needed) to improve quality.

In particular I am considering changing the single filter capacitor for a CRCRC, and changing out the monolithic regulator for a pin compatible super regulator.

I would very much welcome people's opinions both on the "as supplied" quality of the various PSUs, and the wisdom/advisability/effectiveness of my changes.

BugBear

 

[jean-paul]

Please pay attention to the transformer. Unknown cheap stuff tends to hum mechanically. You really can build a custom device for your purpose for not too much money. Highest cost is a nice case.

I don't know the quality of the BingZi in the type you mention but with 220V primaries it seems a version for the chinese domestic market.

Since I designed a simple linear PSU which was offered here as a GB my opinion is coloured but I did not find a cheap linear PSU that had it all. Modification made it more expensive too. Tried several but in the end I made my own.

 

[bugbear]

Please pay attention to the transformer. Unknown cheap stuff tends to hum mechnically. You really can build a custom device for your purpose for not too much money. Highest cost is a nice case.

I'm not really a builder, so I don't have a "box of handy stuff".

To make my own PSU I'd have to buy lots of "bits" like stand-offs and switches and wiring cable and cases and connectors and indicator lights; and a case. The postage and minimum order sizes would be very expensive.

If I buy a ready made, it may be quite as good, but I get all the little bits and pieces I need.

I'm thinking (hoping?) that this is a cost effective route, even if I have to upgrade some parts.

Thanks for your advice on the transformer; lots of the PSUs (if the photos can be trusted) use the same BingZi transformer; is that OK?

BugBear

 

[jean-paul]

Cheap ones are not that good, that is the whole point. Often: buy cheap = high costs later.

The Teradak ones are very good (but they're not cheap at all):

http://forums.slimdevices.com/showt...-AfterMarket-Power-Supply-upgrade-The-TeraDak

The Teradak ones I have seen often have an Rcore transformer. They are built with good quality parts, looks are so so but that is a question of taste.

 

[qwertyadam]

You can buy this board from the following link along with the enclosure, switch etc. from the same sellers. If you also get the toroid transformer from eBay U.K./DE , you'll be able to build a higher quality psu for a lower cost than Teradak.

S22 Super Regulated Linear Power Supply Board 5 30V LPS KG 6800uF 50V Versio PSU | eBay

Assembled S11 Super Linear Regulated Power Supply Board LPS PSU | eBay

 

[matt_garman]

You can buy this board from the following link along with the enclosure, switch etc. from the same sellers. If you also get the toroid transformer from eBay U.K./DE , you'll be able to build a higher quality psu for a lower cost than Teradak.

S22 Super Regulated Linear Power Supply Board 5 30V LPS KG 6800uF 50V Versio PSU | eBay

Assembled S11 Super Linear Regulated Power Supply Board LPS PSU | eBay

Are those authorized by Ti Kan (amb.org)?

I've built two Sigma11 power supplies using boards and some parts from amb.org, and the rest of the parts from Mouser/DigiKey. Cost is a little higher than going through ebay. But it's obvious to me that Ti has put in a tremendous amount of effort designing those power supplies, along with being very DIY-friendly by creating detailed documentation. And he provides support on his forum.

So if the ebay versions of those power supplies are endorsed by Ti, that is cool. But if not, in my humble opinion, it's worth supporting someone who has given a lot to the DIY community.

 

[jean-paul]

This is what the Ebay seller states:

S11 is derived from the σ22, which is the result of a community service project for the audiophile hobbyist. The schematic diagram is open source. The circuit design, as well as the printed circuit board layout are the work of AMB with participation from the DIY community. It is designed to be relatively easy to build, but it is not recommended as a first-time project for the beginner.

However on the amb.org website I see the word "copyright". Since they have their own webshop I think you should ask them if those Ebay boards are authorised (to be sure). The boards don't have any amb.org reference on them and the words "derived from" possibly indicate non authorised.

 

[matt_garman]

This is what the Ebay seller states:

S11 is derived from the σ22, which is the result of a community service project for the audiophile hobbyist. The schematic diagram is open source. The circuit design, as well as the printed circuit board layout are the work of AMB with participation from the DIY community. It is designed to be relatively easy to build, but it is not recommended as a first-time project for the beginner.

However on the amb.org website I see the word "copyright".

That italicized text is directly from the sigma11 web page.

Open source doesn't necessarily mean OK to copy for commercial gain, depending on the license. (To be clear, it is maybe OK to copy for commercial gain, it all comes down to license specifics.)

Actually, here is conclusive text from the Sigma22 website: There are "σ22" clone boards being offered for sale on ebay and elsewhere. They are inferior in quality, made without permission and a violation of the terms set forth on this website. AMB urges not to patronize those unscrupulous vendors.

 

[jean-paul]

Good find, I was looking for that but did not see it (yet).

That italicized text is directly from the sigma11 web page.

Please note that the Ebay seller gives a slightly different name to the design. S11 instead of σ11.

Bloody copycats, Ti Kan has done a lot of work and seeing copies being sold is not nice.

 

[almstsobur]

I ran across this thread looking for info on a DAC power supply and the eBay S11's. No offense to anyone, or AMB, however when I was looking at AMB's website to buy a power supply I came to the conclusion that you cannot buy a power supply. You also can't buy most of the parts from them. I don't mind paying more to support the original designer, but they really only offer the board and a few parts. I may end up going Ali Express or eBay for the simple matter that they sell a completed board. It can take hrs to source 50 components from mouser or Digikey, then a few more hrs of assembly, the risk of screwing up etc. Little frustrating when it's 10x more difficult to support the person who deserves it.