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[Efjay]

I send a digital signal from my pc to a dac. I can lower and raise the volume via MC's internal  volume control. Am I degrading the signal lowering the volume via this method rather than adjusting sound volume via my pre-amp? Similarly, is there an 'optimum' volume level to send from the pc outward?

[Alex B]

MC's internal volume control is about as good as a digital volume control can be.

Since your are adjusting the volume only for playback and the output is not archived to a file it doesn't matter what method you use as long as it sounds fine.

[Efjay]

MC's internal volume control is about as good as a digital volume control can be.

Since your are adjusting the volume only for playback and the output is not archived to a file it doesn't matter what method you use as long as it sounds fine.

Thanks.

I thought this was the case but I wanted to be certain. I've been looking into getting a passive preamplifier that does not have a rmote which means, if I don't want to get up, I need to be able to adjust the volume elsewhere. I didn't want to do so at the expense of sound quality.

[Matt]

To restate what Alex said, MC's internal volume operates on the 32-bit playback chain.

That means you haven't lost any signal information by turning the volume down.  You could turn it back up and it'd be bit-perfect. *

However, if you output that 32-bit signal as 16-bit, you're throwing bits away because fractions have to be rounded off.  So it's best if you can use a 24-bit or 32-bit output mode so this isn't an issue.

* Assuming your input is some reasonable bit-depth less than around 30-bits (a CD is 16).  Also, remember that it's about impossible to hear past 14-bits of precision (especially at low volumes -- i.e. when it's turned down) so this is mostly academic.

[stefansmith]

AFAIK you lose 1 bit for every 6db of attenuation in the digital volume control.

In my case, my dac can only take a 16 bit signal -- but I need a bit of help understanding the chain here. Does the MC take the 16 bit file, pad it to 32bit, make DSP/volume changes and then send it out as 16 bit (meaning no loss below 16bit? Not sweating about this, just curious.

In any case, I try to configure the gain in my amp and preamp to match the output of the DAC best, meaning the volume slider is never really below the 50% mark.

[Alex B]

Does the MC take the 16 bit file, pad it to 32bit, make DSP/volume changes and then send it out as 16 bit (meaning no loss below 16bit?

That is not possible. If you use 16-bit output mode the maximum possible digital volume level uses 16-bit. If you lower the volume level then you have less dynamic range. However, as Matt said, this is always enough for most practical purposes.

For example, if the background noise level in a very quiet listening room is 20 dB SPL and you adjust your fictional perfect amp (=with infinite dynamics range) so that all volume levels from digital silence to maximum volume level can be measured then a full-scale 16-bit signal would produce at least a 116 dB SPL volume level in the room. If you attenuate this signal -36 dB (=> 10-bit signal) this would still produce a range from 20 to 80 dB SPL.

Let's assume that the average volume level of our test signal is 10 dB below the maximum peak. Then the perceived average volume level in the room would be 70 dB SPL. This is rather loud if the listener has adjusted the volume slider to -36 dB (= MC's volume slider in the Internal mode and at about 10% position). Personally, I would expect to hear something like 50 dB SPL at this setting and I would adjust the amp -20 dB. So for me this 10-bit test signal would still have about 20 dB of extra headroom.