Volume controls - possibly silly!

[dave2010]

I generally assume that when there are several volume controls in sequence one should use the last analogue one to control the volume of sound - unless there are strong reasons for doing otherwise. Digital controls should otherwise be set at maximum - again unless there are strong contra reasons.

Digital volume controls could often end up reducing resolution, or that would be my impression, based on a little knowledge of the processes involved. This would be because lower order bits could disappear and this would affect the output at the DAC.

What is the best strategy when there are several digital controls? For example, if one listens to Spotify on an iMac there are the software controls in Spotify - presumably digital, and also the controls on the iMac keyboard, which are perhaps also digital in their effect. Which should one use? Either, both, or should one perhaps have an external analogue control for the best results?

Some software packages seem to link the volume controls in the application to the system volume controls, but others don't appear to do that.

Maybe for Spotify and similar applications it doesn't really matter too much, but it could be good to have more insight into this.

[cycler2]

Not a silly question at all. In fact its one that is commonly asked. The best answer I can offer is that, based on what I have read, the matter is unresolved. Or it depends on the software/digital volume control you might use. Take a look at this thread: http://yabb.jriver.com/interact/index.php?topic=67941.0
Now all software may not behave the same as the JRiver Music Center I use, which claims to handle volume control in 64 bits.

As best I can make out, depending on the software volume control implementation, each 6 db in attenuation reduces resolution by one bit. For a 24 bit DAC, this is probable not significant. The most cogent recommendation I have read holds that one should set the final analogue volume control at the highest level one will listen and then use a digital volume control to attenuate the volume so the listening level is comfortable for each tune. But I understand that using multiple digital volume controls will compromise the sound quality. Hope this helps.

Rich

[DSJR]

For lowest noise, I'd suggest having everything up to max until the LAST gain control in the chain...

In my ancient analogue system, the recommendation of the amp manufacturer (backed up with documented "evidence") is to adjust overall system gain at the power amp, running the preamp line stage (and interconnects) quite hard so the volume control was set fairly high.. Hope this can be adapted (sort of) to your digital situation..

[stevekr]

I had similar problems when using a power amp with L/R volume controls into an active pre-amp. I thought turning the controls on the power amp to full and using the pre as the main control would be best as that seemed the logical thing to do.

However it turned out that that the best way was to play a 100hz test tone cd recorded at 0db through the power amp with the pre's control set to full and turn up the controls gradually on the power amp until the meters started to show the amp was starting to clip then back off a bit. The power amp's controls ended up at about the ten O'clock position and everything sounded great.

If you're using digital controls I'd stick with what you're doing or consider getting a pre-amp with a good quality volume pot and keep the digital controls set to full. Hope this helps.