I do not agree with that inexpensive part. Simply look at the prices for analog potentiometers that are specified at anything approaching 0.2 dB across at least 60 dB
range. I agree that reliable AC voltmeter can be had for 50$ and that its absolute accuracy is not required for consistent result of matching we need.
Problem is that for the most part I DO NOT WANT digital volume control - as it means DSP and that means PCM. Even if it is accurate to within 0.000000.....1 dB.
Not on analog sources and not on DSD. Which brings us back to quality analog potentiometer$ / attenuator$. And THESE can be source of trouble - by the time they are "good enough", that means money.
The first stupid thing any analog volume control device must avoid like a pleague is - microphonics. Unfortunately anything but trivial and taken for granted to be free from it.
It is fair to say that multichannel ( > 2 ) equipment can not be built with analog potentiometers ( differences become practically unmenageable, with the po$$ible exception of attenuator$$$ ) - but for all practical purposes, multichannel is already in PCM and yet another PCM stage will do no additional audible harm in such a system.
Well I can't do anything about an irrational fear of DSP or PCM processing. I would imagine that is an issue for a small minority of people. Most sources these days are going to be digital. By your own description digital volume bypasses issues of consistency, microphonics and fineness of control.
If you wanted something better in analog control you can go with switched resistors. It is a problem created by eschewing digital processes.
Edited by esldude - 8/15/14 at 2:29pm