08-23-15: Cerrot
You lose res with every reduction in volume in (most) digital volume controls.Cerrot
Only if the Berkeley is below 75% of full output, it's called "Bit Stripping"
Your Berkeley Dac from the specs I saw gives out a massive 6v XLR or 3v SE. And your Sanders Magntec Amp only needs 2v for full output.
If you have to your Berkeley volume below 75% you get the volume down to where you want, this proves you have more than enough system gain without the need of extra gain that active preamp give.
And your Berkeley dac output stage would even have better drive than most preamps have.
So to get a valid idea you somehow need to reduce your system gain so the volume of the Berkely is used at 75% or over.
From what I saw on the Berkeley site you maybe able to change the analogue's amps gain setting from 3v to 2v somewhere (maybe inside)
"Unbalanced analogue output level setting: 3.25Vrms maximum, 2Vrms or lower recommended"
This then should allow you to use it's digital domain volume control at or above 75% of full output which maybe change your opinions about loosing resolution and "warmth".
Cheers George