manleyelop wrote:...some of my ch faders have been hovering around -20 mainly drums & bass & im wondering if that's a bad way of doing things.
It would only be 'bad' if, with the faders for those channels at unity, the signals would be so loud that they overload the output of the desk -- because in that situation you're clearly driving way too much signal through the channel strip and risk major distortion.
But if you've set the channel input gains (using PFL, perhaps) so that the signal averages around or a little below the 0VU mark on the meters, then you have the ideal headroom margin, and you're simply pulling the fader back because you don't want much of that particular signal in the mix, for whatever reason.
If that's the case, then yes, it is an acceptable way to work... and a lot of people often find themselves doing exactly the same thing...
... but there are some practical implications that may or may not be important.
I've already mentioned the poor fader resolution when working far away from the unity mark, so if you want to tweak the source level very slightly that would be more difficult and less precise with the fader at -20dB instead of around 0dB.
It's also less convenient when switching between sound check and gig if there's a warm-up band in between, since it's much easier to push all the faders to unity and know you have a reasonable starting point for the mix, rather than try to remember Ch3 has to be at-20, Ch5 at -35 and so on...
And then there's the disparity between the levels being sent to pre-fade and post-fade Aux outputs, meaning you'd have to have wildly different aux send control positions for the same actual output level... which could become confusing -- or extremely unpleasant if you decide to swap a send from post to pre for some reason!