Fixed volume output

[Staresyj]

On set up I activated fixed volume output with line out level set at 2 Vrms. At slightly louder than normal listening level, I am hearing some distortion. I lowered the Vrms to 1 and lost some clarity but also think I lost some of the distortion. Is this something others have played with? My current set up is Wiim to DAC (set at 100% output no pre-amp reduction)

 

[d6jg]

Surely the Vrms applies to the Aux Out only i.e. line out?
If you are connecting by Optical or Coaxial to a DAC Vrms shouldn't have any bearing but setting the output to 100% does - or it should but WiiM haven't said what the underlying audio sub system actually is - my guess is ALSA.

 

[DryTortuga]

What brand/model DAC. Assuming you’re referring to the DAC volume at 100%? Some DACs that don’t defeat a volume control run hot on the analog outs (e.g., SMSL)

 

[Staresyj]

Surely the Vrms applies to the Aux Out only i.e. line out?
If you are connecting by Optical or Coaxial to a DAC Vrms shouldn't have any bearing but setting the output to 100% does - or it should but WiiM haven't said what the underlying audio sub system actually is - my guess is ALSA.

yes that would make sense as I’m using optical to the DAC so I’m guessing Vrms has no skin in the game if I’m not using line out? But I thought I heard a change in tone when I altered the Vrms from 2 to 1!, maybe I made it up in my head!

 

[Staresyj]

What brand/model DAC. Assuming you’re referring to the DAC volume at 100%? Some DACs that don’t defeat a volume control run hot on the analog outs (e.g., SMSL)

Topping e30ii, which is set at just DAC and no volume out adjustment down the scale.

 

[d6jg]

What source are you playing? I read there was some issue with Airplay where there is conflict with fixed volume.

So are you saying that the Topping is set to take 100% in, do the DAC bit and send it out at full line level but there is distortion?

 

[onlyoneme]

And EQ is off?

 

[Staresyj]

What source are you playing? I read there was some issue with Airplay where there is conflict with fixed volume.

So are you saying that the Topping is set to take 100% in, do the DAC bit and send it out at full line level but there is distortion?

Was streaming Qobuz connected directly from the Wiim app, I haven’t bothered with AirPlay yet. Yes, Topping set to DAC only mode, so 100% in, does it thing and spits it out to the amp, and at nothing more than a decent sound volume, I thought I could hear some distortion.

 

[Staresyj]

And EQ is off?

Yes EQ off

 

[onlyoneme]

As @d6jg said Vrms setting has nothing to digital output. So you shouldn't hear any difference.
EQ settings can affect digital output, volume level and resolution settings can affect it also. Fixed volume equals to variable one at 100% level.

 

[Staresyj]

As @d6jg said Vrms setting has nothing to digital output. So you shouldn't hear any difference.
EQ settings can affect digital output, volume level and resolution settings can affect it also. Fixed volume equals to variable one at 100% level.

That’s very helpful, I think I confused the note in the Vrms setting about possible distortion at 2Vrms not thinking it through properly because I’m not exiting the Wiim via the line out! So the Wiim is doing what it should so any sound distortion can be narrowed down to DAC and Amp, as the speakers were not being driven hard.

 

[DryTortuga]

I’ve definitely noticed a difference in my OG E30 depending on what is providing power - cheap wall wart vs better wall wart vs a P50 power supply. Biggest difference being between wall warts.

 

[Staresyj]

I’ve definitely noticed a difference in my OG E30 depending on what is providing power - cheap wall wart vs better wall wart vs a P50 power supply. Biggest difference being between wall warts.

That could be a point worth exploring. I am providing power with a Belkin battery pack throwing out 2.4amps

 

[DryTortuga]

Technically, a stable battery is your best power source.

 

[onlyoneme]

Technically, a stable battery is your best power source.

Depends. DC-DC converters can be noisy.

 

[Staresyj]

Technically, a stable battery is your best power source.

Do you mean a battery pack should be stable or not?!

 

[Staresyj]

Depends. DC-DC converters can be noisy.

I’m going to try an Apple charger

 

[DryTortuga]

I don’t know about your particular Belkin and can’t speak to the comment on DC-DC noise. I just know some batteries are better than others at delivering power. It’s not something I personally use, but for others it seems a quest. I have read that the Apple warts are pretty good. I think you only need 1A for the Topping.

 

[DryTortuga]

I should add I would be surprised if using the Apple wart over the Belkin battery makes a difference. If it does clean up the sound then I’m suspect about the condition of the battery. Belkin isn’t usually considered low quality products.

 

[riepa]

Who cares about your batteries? The topic is about something else. I rely only on my hearing and it tells me that changing the Vrms changes the quality.
The basis of good sound = a quality preamplifier, which will not be here until the company makes another relay-based wheel with switchable op-amps. It would be ideal if they could still show the level of sound degradation depending on the selected setting, but that will never happen here either. The only thing they can tell you is what factors/settings can affect the sound quality, like the educational guide.