SMSL SU-1 Power and USB help for newbie!

[ynot311]

Hello, I have just joined this forum. I have looked through the forum to see if I could find some kind of answer relating to my question but no luck.

Basically, I just purchased the SMSL SU-1 dac. I mainly purchased it to output from my computer as alternative to a sound card.

So my question is, if I also want to run a linear power supply on the SU-1 and use the computer as the source, is there any way to achieve this? Would a USB C splitter work or could this cause issues?

Any guidance would be appreciated.
Thank you.
Tony

 

[Doodski]

Why a linear supply?

 

[JSmith]

Hello, I have just joined this forum.

Hey, welcome to ASR.

run a linear power supply on the SU-1

Honestly, there is no need to waste your funds on a linear PSU... it's not going to provide any benefit at all.

Would a USB C splitter work or could this cause issues?

No... you can't split power and data into two separate lines and then combine them for a single USB-C input on the DAC AKAIK.


JSmith

 

[ynot311]

Why a linear supply?

Im told an external supply will make it sound better???

 

[Doodski]

Im told an external supply will make it sound better???

The switch mode pulse width modulation power supply and voltage regulation that powers the unit is suitable for the task and is in spec. The linear supply will not improve things and may in fact make things worse.

 

[staticV3]

Im told an external supply will make it sound better???

An external supply may help in edge cases such as:

-Computer struggling to provide enough current/voltage to the SU-1 for some reason
-Ground loop induced mains hum coming from the SU-1 when connected via USB
-USB noise interference (audible mouse/GPU activity) coming from the SU-1 when connected via USB.

All of these can be fixed by connecting to the computer via Toslink and powering the SU-1 from a good quality phone charger (e.g. Apple).

Beyond that, switching to a linear power supply will achieve nothing but an increase in your power bill and room temperature. There is no point.

Similarly, switching to Toslink and an external power supply if you do not have any of the above listed issues will also achieve nothing.

 

[ynot311]

An external supply may help in edge cases such as:

-Computer struggling to provide enough current/voltage to the SU-1 for some reason
-Ground loop induced mains hum coming from the SU-1 when connected via USB
-USB noise interference (audible mouse/GPU activity) coming from the SU-1 when connected via USB.

All of these can be fixed by connecting to the computer via Toslink and powering the SU-1 from a good quality phone charger (e.g. Apple).

Beyond that, switching to a linear power supply will achieve nothing but an increase in your power bill and room temperature. There is no point.

Ok, just going by things I have been reading online. Most people state that plugging an external supply in rather than using the usb from the pc, improves the sound. That may be the case if you use the other inputs like optical or coaxial, but in my case, I want the audio out from the usb as well as power so i cant see how to do that.

 

[DVDdoug]

Im told an external supply will make it sound better???

Hopefully not by anyone here at Audio Science Review. MOST "audiophile" related websites are FULL of nonsense. This is one of the few rational-scientific resources.

I assume you're not actually hearing anything wrong with the sound... There's nothing specific you want to "improve", right?

Ignoring EQ/tone controls or other "processing" and ignoring any gross problems like one dead channel or one channel being louder than the other, etc., with electronics there are only 3 characteristics to "sound quality". Noise, distortion, and frequency response. Frequency response is almost always flat across the audio range and distortion is almost always below audibility unless you over-drive an amplifier into clipping (like trying to get 110W out of 100W amplifier).

You can also get digital clipping if you boost with digital EQ and don't adjust-down the overall level to compensate. (That's not the fault of the electronics. It's the nature of digital.)

Sometimes there can be noise (hum hiss or whine in the background). If you aren't hearing noise from your soundcard the DAC is unlikely to sound any different (in a proper level-matched, blind, ABX test?).

USB power from a computer is notoriously noisy and sometimes the noise gets into the analog electronics. (Digital is normally completely immune to noise.) In that case a separate power supply (linear or switching) can help but the best way to use one is to get a DAC with its own power supply.

Both linear and switching power supplies can put-out "clean DC." With a "bad" linear supply power line hum can leak-through and that's in the audio range. Switching power supplies operate above the audible range. That makes any noise easier to filter-out, and if any leaks-through it's ultrasonic so you can't hear it. USB power (from a computer) has an additional issue with all kinds of digital signals at all kinds of frequencies inside the computer. But most DACs can filter it out. It's a more common problem with audio interfaces on the input (ADC side) because the high-gain microphone preamps amplify the noise.

With speakers and room acoustics (or headphones) it gets more complicated and the main issue is usually frequency response. Different speakers or different headphones will ALWAYS sound different (better or worse).

And see Audiophoolery.

 

[staticV3]

Most people state that plugging an external supply in rather than using the usb from the pc, improves the sound.

In most cases it's just confirmation bias/sunk cost fallacy/placebo.

Improvements can be had only in one of the edge cases above.

in my case, I want the audio out from the usb as well as power so i cant see how to do that.

You can supply power externally and get the same advantages as Toslink while sending audio via USB, using a USB isolator like the Topping HS01.

But again: Switching to an external power supply if you do not have any of the above listed issues will achieve nothing. The sound will not change.

 

[ynot311]

Hopefully not by anyone here at Audio Science Review.

I assume you're not actually hearing anything wrong with the sound... There's nothing specific you want to "improve", right?

Ignoring EQ/tone controls or other "processing" and ignoring any gross problems like one dead channel or one channel being louder than the other, etc., with electronics there are only 3 characteristics to "sound quality". Noise, distortion, and frequency response. Frequency response is almost always flat across the audio range and distortion is almost always below audibility unless you over-drive an amplifier into clipping (like trying to get 110W out of 100W amplifier).

You can also get digital clipping if you boost with digital EQ and don't adjust-down the overall level to compensate. (That's not the fault of the electronics. It's the nature of digital.)

Sometimes there can be noise (hum hiss or whine in the background). If you aren't hearing noise from your soundcard the DAC is unlikely to sound any different (in a proper level-matched, blind, ABX test?).

USB power from a computer is notoriously noisy and sometimes the noise gets into the analog electronics. (Digital is normally completely immune to noise.) In that case a separate power supply (linear or switching) can help but the best way to use one is to get a DAC with its own power supply.

With speakers and room acoustics (or headphones) it gets more complicated and the main issue is usually frequency response. Different speakers or different headphones will ALWAYS sound different (better or worse).

And see Audiophoolery.

NO, noone on this site. Just on google and youtube. Honestly I have just got it and not set it up yet. So I guess I should do that first Then work out if it sounds ok or not. Just pre-empting.

 

[Carl-Fosi Audio]

A Cable like this.