Archived from groups: rec.audio.pro (
More info?)
"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:9d2dnZPWwZo7avfcRVn-tA@comcast.com...
> "Yuri T." <tymish@hotmail.com> wrote in message
> news:f7d8b3cd.0410111200.4cc573c9@posting.google.com
> > Just looking at switchers and passive line level volume controls for
> > powered speakers. Seems easy enough to build. I suppose you would need
> > a decent stereo log taper pot.
>
> There's the rub.
>
> >What if it's a balanced line?
>
> You have two options.
>
> (1) Use a single pot hooked as a variable resistor, and drive each end
with
> the same value resistor, each resistor about half the resistance as the
pot.
> Downside - you accept a minimum of 6 dB of loss.
And a load on the mixer that changes with the level setting. Probably not a
big deal, but worth keeping in the back of your mind.
> (2) Use dual pots with the bottom ends tied together. Downside - you
accept
> reduced common-mode rejection and have the fun of trying to find a
4-section
> log pot for a stereo control.
If you're gonna do that, it's probably easier to make a switched 4-gang
attenuator than trying to find a 4-section log pot. There are diagrams with
suggested parts value in old issues of Audio Amateur, and probably somewhere
on the web.
Peace,
Paul