Is it possible for a power supply to affect sound quality?

[Superdad]

Digital  audio circuits respond VERY favorably to power supplies with very low broadband output impedance.  
Much has been written about this.  Search for posts on the subject by @paulhynes and @JohnSwenson.

[Superdad]

13 hours ago, Superdad said:

Digital  audio circuits respond VERY favorably to power supplies with very low broadband output impedance.  
Much has been written about this.  Search for posts on the subject by @paulhynes and @JohnSwenson.

I‘ll just repeat...

[Superdad]

5 hours ago, fas42 said:

Once we get into the arena of power amps, then it's gets messy - old school power supplies are quite primitive in their ability to maintain the nominal DC voltage...

 

Actually, very few large power amps have regulated linear power supplies.  The amplifier chassis would need significant additional heat sink area just for the the pass transistors required to go with the regulators.

That’s not to say that state of the art power amps all just have simplistic transformer>diode>capacitor supplies.  Some are quite sophisticated, and if you ask any serious designer they will tell you that the power supply is crucial to the performance of their amps.

[Superdad]

On 6/18/2020 at 4:55 PM, SJK said:

Can a linear supply actually make any difference? 

 

44 minutes ago, StephenJK said:

If you, and so many others actually went back and read the OP, it was with a detailed and specific focus on outboard linear power supplies only, not that you seem to know or care. 

 

And, how any linear power supply based on an old school breadboard diode/filter network could or would compare to some overpriced boutique variation that does the same thing for tens or hundreds the cost. 

 

Hi Stephen:

As I stated several times prior, digital audio circuits respond VERY favorably to power supplies with very low broadband output impedance. 

Your "old school" diode/filter network will not compare in that regard to some of the better offerings focused on that.

You can read a bit about our designs at: https://uptoneaudio.com/products/js-2-linear-power-supply or https://uptoneaudio.com/products/ultracap-lps-1-2

(We are not into "snake oil" when it comes to power supply design. If we were we would not spend so much to build them!)

Or you can read a this good post from Paul Hynes:

 

[Superdad]

1 hour ago, Abtr said:

Hi John. I use a 7.5V SMPS to provide clean 5V power to the USB input of a DDC (Schiit Eitr). I inserted a small, LT3045 based, 5V regulator board (ldovr.com) in the output power cable of the SMPS at about 4 inches from the end.

 

The problem I see there is that you are introducing copious amounts of leakage (common-mode AC traveling over DC connections) from use of an SMPS--and that's going tight into the USB input of your Schiit device.

 

And for anyone who does not think is an issue, look no further than the clever folks at Schiit:

For any of their products which run from an external supply, they put the rectifying diodes and regulators inside the component--and include an external 6V AC transformer wart instead of an AC>DC SMPS.

Unlike with an SMPS--where 'Y' capacitors right across from primary to secondary are required--the only coupling capacitance of Schiit's small transformer is whatever small amount passes on the windings.