Do you need linear power supply for DACs?

[Veri]

Recently, I’ve noted that he has been offering LPS options for many of the products he designed to work very, very well with switching power supplies. He charges a cost premium for these LPS versions and they perform no better. He does it because people have their minds made up about LPS vs. switching power supplies despite his careful design and research.

The choice to use a LPS versus SPS versus batteries has less to do with inherent performance superiority than it has to do with value engineering and customer preference trade offs.

Very aptly put.

 

[deafenears]

No disrespect to the Chinese, but the cheap ones are also much, much more likely to burn your house down.

https://lygte-info.dk/info/ChargerIndex UK.html is another useful site, take note of the "Safety" column.

 

[Xyzzy]

hmm... so you used a bunch of low res test equipment to convince yourself of what you think you already know. Did you listen to any music using a linear vs switched power supplies on a decent dac or with decent audio equipment? Of course not.

 

[signalpath]

Have been designing high-end audio for 30 years using LPS and SPS. When done with attention and care, both can be exceptional. When done wrong, both can be awful. About 1/2 our products use LPS, but we're moving more to SPS mostly for reasons of heat, weight, size, and EMR. There's nothing magic about either topology, though I do have a certain nostalgia for big toroids and discrete linear regs.

 

[tw99]

hmm... so you used a bunch of low res test equipment to convince yourself of what you think you already know. Did you listen to any music using a linear vs switched power supplies on a decent dac or with decent audio equipment? Of course not.

A truly insightful post that shows you have understood what ASR is all about.

You might also like this thread:

https://www.audiosciencereview.com/...iles-posting-at-asr-for-the-first-time.17598/

 

[Veri]

hmm... so you used a bunch of low res test equipment to convince yourself of what you think you already know.

Question to you oh smart internet person, if this cheap, budget, low res equipment has excellent power handling and noise rejection. Then WHY would a much more costly, "hi-res" piece of equipment need that ultra linear power supply? Because more is always better?
Please....

 

[Killingbeans]

Did you listen to any music using a linear vs switched power supplies on a decent dac or with decent audio equipment?

I don't get it. Why should a "decent DAC" (whatever that means) have a lousy PSRR?

 

[Rock Rabbit]

Although ultrasonic cannot be detected by human, but these signal will be passed to amplifier and then loudspeaker, would they have any negative effect on the final signal?

At the end of the day, we don't hear the waveforms the DAC produced. We hear the waveforms loudspeaker produce. We don't know whether these ultrasonic peaks will affect speaker yet.

In general there's no effect, tweeter impedance start to grow then a Zobel network takes the tweeter energy so everything is fine.
https://audioxpress.com/article/voice-coil-lab-notes-improved-zobel-network

 

[nhatlam96]

This is my recap, for me to understand better. Therefore please ignore this post, it's just for my personal use.

What power supply is best for DACs?
1. Topping D50 USB powered vs Sbooster BOTW.
Identical performance at 0-20kHz. Better performance above 20kHz, but that doesn't matter because worst case scenario is at -125dB and it's outside of audible range. Conclusion: No audible difference between USB powered vs Sbooster BOTW.

2.Wyrd4sound (linear) vs Sbooster Eco (linear) vs Topping DX3 Pro supply (switching).

The power supply noise spectrum shows a measured difference between the units, but that is of no concern, because

we don't listen to power supply wires and those waveforms go through filtering stages even in cheapest DACs.

Conclusion:
No audible difference between Wyrd4sound (linear) vs Sbooster (linear) vs Topping DX3 Pro supply (switching).

3. Topping E30 USB powered vs smartphone charger. Conclusion:

I tested with a Samsung phone charger and it was basically the same as USB.

Overall conclusion:
No audible difference between: Linear, switching, smartphone charger and USB.

 

[Veri]

The conclusion is entirely correct

 

[gasolin75]

^ agree, D50 runs ~10hours with 10.500mAh powerbank. When pb runs out D50 just turns itself off, no fading or SQ chance.

I get up to 4 days of heavy use with a 20000 mAh power bank

 

[solderdude]

A powerbank also is a switch mode power supply.
The only reason to use it would be when one is bothered by weird noises when using an USB port or wall wart or when it is portable usage.

 

[gasolin75]

Atm im trying a samsung galaxy s10+ charger to hear if it makes a difference to a 20000 mAh power bank (Topping E30)
i think there is a difference, might just be a placebo effect

 

[Jimbob54]

Atm im trying a samsung galaxy s10+ charger to hear if it makes a difference to a 20000 mAh power bank (Topping E30)
i think there is a difference, might just be a placebo effect

The only way to determine whether there is/ is not an audible difference is to blind test. Ideally double blind but probably not possible in a home setup. But if you have a friend / partner, blindfold yourself and get them to switch power supplies (or not) and record results as to whether you "hear" a difference between switches. They record what they did (or didnt ) do. If you detect a switch when a switch actually occurred a significant portion of the time , then there may be something worth investigating.

But I would guess your results would show no better than a coin toss when you personally dont know if there has been a switch and to what.

 

[gasolin75]

There is a problem, you can't just test it by pressing a button, you got to take the cable out of the dac and use the other cable, wait for the dac to turn on and the pc to recognize it.

In many reviews they say the topping E30 is sensitive to "clean" power What is clean power ? I know what clean (watt) power is.

https://soundnews.net/sources/dacs/topping-e30-dac-review-entry-level-overachiever/

 

[Jimbob54]

There is a problem, you can't just test by pressing a button, youto take the cable out of the dac and use the other cable, wait for the dac to turn on and the pc to recognize it.

In many reviews they say the topping E30 is sensitive to "clean" power What is clean power ? I know what clean (watt) power is.

https://soundnews.net/sources/dacs/topping-e30-dac-review-entry-level-overachiever/

Well, @amirm has tested effects of different power supplies with DACs and found there to be minimal measurable difference between power sources for DACs , all of which should be below audibility. Not the e30 though.

If there was an audible difference in this instance, even with a slow switch, you should be able to reliably tell which power was used if you dont know what is plugged in. You cant make that conclusion if you listen/ switch eyes open, the ears just aren't reliable.

So, basically, either do a test as above , see if anyone has taken reliable measurements of the e30 with different PS that suggest a difference should be audible (I doubt), or (and this would be my suggestion) use whichever form of PS is most convenient in your use case and be happy

 

[Jimbob54]

There is a problem, you can't just test it by pressing a button, you got to take the cable out of the dac and use the other cable, wait for the dac to turn on and the pc to recognize it.

In many reviews they say the topping E30 is sensitive to "clean" power What is clean power ? I know what clean (watt) power is.

https://soundnews.net/sources/dacs/topping-e30-dac-review-entry-level-overachiever/

PS to my last post- see #169 above. And ignore people on the internet who like to say that their magic ears tell them differences exist without doing proper testing and/ or measurements.

 

[gasolin75]

PS to my last post- see #169 above. And ignore people on the internet who like to say that their magic ears tell them differences exist without doing proper testing and/ or measurements.

not that fare in the thgreas only page 8

 

[gasolin75]

Came across this blog post, measuring a bunch of USB chargers.
http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html
It's old AF, but shows that name brand USB power supplies are usually considerably cleaner than the bottom of the barrel Chinese options. I've scoped my desktop and laptop 5V USB rails, and they are significantly worse than my Apple chargers.

Looks like the samsung charger is a safe choice

 

[sjeesjie]

I want to thank this forum so much!

Whenever I’m about to fall into the hands of snake oil salesmen (they are everywhere, they don’t even know it themselves most of the time), I visit this forum and I’m back with both feet on the ground.