Please suggest a 12VDC power supply for my Musical Fidelity V90 DAC.

I am in the process of reorganizing my home audio system. One of the desired elements for this project is a mains-powered linear regulated 12 volt DC power supply for my Musical Fidelity V90 DAC. The DAC comes with a small "wall wart"-style switching power supply rated at 12V/500mA, so I am searching for a manufactured PS or a DIY project that will meet those specifications.

I have never built a DIY power supply before, and though I have lately studied audio PS design I would be more comfortable building a proven existing design or buying a good manufactured unit. I would appreciate suggestions for one or the other. These are my requirements:

A low-noise linear regulated design meant for or adaptable to audio use;

12 volt DC output with 500mA capability;

Mains powered, not wall wart, designed for USA 110-120V;

If a manufactured unit, currently available and in new condition, from a USA supplier if possible;

If a DIY design, readily available parts sourced from suppliers such as Digikey or Mouser.

I can provide and install the circuit board, enclosure, mains cord and switch, and cord and connector to the DAC for a DIY design.


Thanks to all who respond. I look forward to your replies.
 
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The DAC comes with a small "wall wart"-style switching power supply rated at 12V/500mA, so I am searching for a manufactured PS or a DIY project that will meet those specifications.

Does it work? If so there should be no problem.

I know you said you are looking for a linear supply, but there is nothing wrong with SMPS. In fact, they have one very distinct advantage over linear supplies... They do not hum. You get nice clean well regulated DC.

It was once true that SMPS would throw off a lot of interference and you could see poor filtration on the DC outputs... but those days are long gone. The new warts and bricks, made in the last 5 years or so, work at much higher frequencies, don't drive the chopper so hard and are generally far more well behaved.
 
the best linear psu i have tried is the sigma22 (bipolar version). With the cap multiplier replaced with something better (to my ears) like CRC filter type or even lm317, it can sound quite spectacular. Good for small power amps too!

otherwise Salas shunt regs are very though to beat if you can bias the the power mosfets with hundreds of mA.
 
Thanks to all for the replies. I have not yet reached a decision, so I will appreciate any more suggestions that are offered.

Slighty off topic, does anyone have experience with the iFi iPower 12 volt "Super Switcher" powering a DAC? I have read conflicting reviews on this device, and I would value the opinions of diyaudio members on the subject.
 
Does it work? If so there should be no problem.

I know you said you are looking for a linear supply, but there is nothing wrong with SMPS. In fact, they have one very distinct advantage over linear supplies... They do not hum. You get nice clean well regulated DC.

It was once true that SMPS would throw off a lot of interference and you could see poor filtration on the DC outputs... but those days are long gone. The new warts and bricks, made in the last 5 years or so, work at much higher frequencies, don't drive the chopper so hard and are generally far more well behaved.
Our ears are very sensitive to hum. If we have a poorly designed linear supply, it is easier to detect.

Even modern SMPS uses higher frequencies, intermodulation can mess up the audio range from a poorly made wall wart. How do I select a good SMPS for audio use without paying the premium for the specialty units?
 
How do I select a good SMPS for audio use without paying the premium for the specialty units?

First of all ... SMPS do not hum. That's their big advantage almost pure DC with no ripple.

There's nothing magic or special about audio. It's just electronics that needs power to work.

The easy answer is to use the supply that came with the DAC, unless it's somehow gone defective on you. Just about any 12volt SMPS even the wall wart kind is going to run a DAC just fine.
 
SMPS for audio

First of all ... SMPS do not hum. That's their big advantage almost pure DC with no ripple.

There's nothing magic or special about audio. It's just electronics that needs power to work.

The easy answer is to use the supply that came with the DAC, unless it's somehow gone defective on you. Just about any 12volt SMPS even the wall wart kind is going to run a DAC just fine.
I do not have the faith on SMPS. Yes, it can be very good is designed properly, but not the cheap wall warts. There is NO such thing as pure DC.

The SMPS is complex. The generation of high-amplitude, high-frequency energy that the low-pass filter must block to avoid electromagnetic interference (EMI), a ripple voltage at the switching frequency and the harmonic frequencies thereof.

Very low cost SMPSs may couple electrical switching noise back onto the mains power line, causing interference with devices connected to the same phase, such as A/V equipment. Non-power-factor-corrected SMPSs also cause harmonic distortion. This is particularly true for power amplifier. DAC PS is another open question.

You may believe that those traditional thinking might not be valid. But the effect is still audible until proven otherwise.
 
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I have no experience in building SMPS for audio use and would very much like to learn more about this subject. For those interested, you can check this thread last year on SMPS for audio power circuit.

Ebay: 500W +/-70V PSU Audio Amp High-power

For DAC power supply requirements, there are many good discussion on the lengthy (500+ pages) ES9038Q2M thread, but it is difficult to summarize. This thread had many actual measurement and discussion on PS effect on audio quality.

ES9038Q2M Board
 
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I do not have the faith on SMPS.
...
But the effect is still audible until proven otherwise.

That takes about 3 seconds with an oscilloscope.

Seriously, you don't think a credible manufacturer would sabotage their own high end products by providing an inadequate power supply... do you?

Subjectivism has it's merits. But it also has it's limits. We all (me included) hear stuff that isn't really there or we don't hear stuff that is. The human ear is a very unreliable instrument for judging anything but enjoyment.

I listen to music subjectively. For the rest, I get out the test gear.
 

jean-paul

Ex-Moderator
2002-09-20 7:20 am
Germany
The only reason SMPS are used is their price (also translates to less weight, less copper, small or no heatsink, etc). It did not help that standby power had to be reduced in various countries.

They have the tremendous feature to die after a few years. Even modern ones transmit more EMI/RF than a modern well designed linear PSU. A good SMPS is still followed by a low noise LDO reg :)

For low power applications a linear PSU is hard to beat. In power amplifiers good results can be obtained at a far lower price when using SMPS. However, I would not bother to think about SMPS when powering a DAC with 12V @ 0.5A max.
 
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Does it work? If so there should be no problem.

I know you said you are looking for a linear supply, but there is nothing wrong with SMPS. In fact, they have one very distinct advantage over linear supplies... They do not hum. You get nice clean well regulated DC.

It was once true that SMPS would throw off a lot of interference and you could see poor filtration on the DC outputs... but those days are long gone. The new warts and bricks, made in the last 5 years or so, work at much higher frequencies, don't drive the chopper so hard and are generally far more well behaved.

I bought 4 Chinese SMPS 12v 2 amp mains adaptors off ebay.
Within a week all had failed.
I bought some better ones from CPC and they all have been good.
The Chinese ones just went bang.
 

kodabmx

Member
Paid Member
2011-10-31 1:00 am
Toronto
The only reason SMPS are used is their price (also translates to less weight, less copper, small or no heatsink, etc). It did not help that standby power had to be reduced in various countries.

They have the tremendous feature to die after a few years. Even modern ones transmit more EMI/RF than a modern well designed linear PSU. A good SMPS is still followed by a low noise LDO reg :)

For low power applications a linear PSU is hard to beat. In power amplifiers good results can be obtained at a far lower price when using SMPS. However, I would not bother to think about SMPS when powering a DAC with 12V @ 0.5A max.

Can you hear the difference between different battery chemistry, too? :rolleyes:
 
I bought 4 Chinese SMPS 12v 2 amp mains adaptors off ebay.
Within a week all had failed.
I bought some better ones from CPC and they all have been good.
The Chinese ones just went bang.

No... not Chinese... EBay. When you buy on EBay you never knoe exactly what you are getting. Counterfients, recovered parts, etc. are very common there.

I've been buying from Amazon and have no problem. All the SMPS I get are made in China... so it's not geographical, it's who you're buying from.
 

kodabmx

Member
Paid Member
2011-10-31 1:00 am
Toronto
I bought an LED work lamp at Home Depot. Made in China of course. The LED driver burnt out in a month. Since I hate dealing with warranty for such an easy fix, I just ordered the CHEAPEST 800mA LED driver I could find from eBay. Came in from China in about 6 weeks, and has been working for years now. Nothing wrong with Chinese, just some poor designs. I've been ripped off by people in the USA more than anywhere else FWIW but even then I can count the instances on one hand.