Re: Mixer units
Re: Mixer units
- Subject: Re: Mixer units
- From: Robert Grant <email@hidden>
- Date: Tue, 11 Mar 2003 20:23:28 -0500
My problem is that a hosting app should provide a nice place for mixing
the output. If the mixer can't pan or balance stereo sources then we
should have a way of getting mono output from every music device. I
can't imagine attempting to do a mix by leaping to 20 different stereo
devices and fiddling with each of their individual pan controls on 20
different custom GUIs. Does that sound practical to anyone else? As an
example many Reason users take the individual outs from the ReDrum and
route them into the ReMix even though the redrum has a stereo output
and pan controls for each drum sound because the ReMix gives them
better and more consistent control.
Somebody more informed than me can probably tell us how many of the big
name virtual synths are stereo and whether they provide mono outs or
at least left and right individual outs.
Here's a thought - anyone thinking of writing a stereo bus to L/R mono
busses AU? It would help a lot I think.... ;-)
I'm trying to figure out a way to best represent the various busses and
the available routing options to users. I was going to have three
different representations for mono, stereo and multi-channel, but now
it strikes me that the adaptability of the effects busses means that
either it's impossible to know before everything is wired up (i.e.
wiring an effect to a mixer input could be either stereo or mono
depending on the source that gets connected to the effect input) or
(and hopefully this is the case) that it doesn't matter and the same
representation could be used for everything. But it just seems that
that is too simple and would end up confusing the user because they
don't know what's stereo or mono. Or perhaps there's a third option
which would be use an indeterminate connection until a concrete device
(a device with a distinct set of channels) is added to the graph and
then annotate the connections appropriately.
Am I making any sense?
Robert.
On Tuesday, March 11, 2003, at 04:44 PM, Brian Willoughby wrote:
[ > From: Bill Stewart <email@hidden>
[ >
[ <snip>
[ > We haven't implemented panning for stereo sources..
[ >
[ Is panning stereo sources really hard?
Perhaps it isn't hard, but there are many different techniques for
designing
pan pots - more than you might think.
Panning a mono source to stereo is probably best with a curve that is
3 dB
down in the center position. However, typical room acoustics are not
precise,
and the signals from each speaker may not precisely combine, so using
more or
less than 3 dB might be better.
Panning a stereo source is usually implemented such that each channel
is
completely unaffected in the center position. Turning the knob left
will
slowly attenuate the right channel, and vise versa.
Another issue to consider is that you might not ever want a channel to
completely go silent, since this is not natural sounding in headphones.
I recently attended the local AES (Audio Engineering Society) meeting
devoted
to the decibel and audio perception. During this talk, I learned that
some DJ
mixers actually drop more than the usual amount in the center position,
especially for the cross faders, because two beat synced dance tracks
tend to
have lots of in-phase signal, and there is less clipping if the faders
drop the
signals a little more in the center position. Unfortunately, I did
not take
notes on the actual dB drop that was measured and mentioned.
The design behind pan pots and cross faders is something that I've
never seen
documented on equipment, but there are certainly a wide variety of
implementations. Given the right equipment, someone could measure
various
popular mixer products on the market, and "steal" their dB
pan/crossfader
curves.
So, it might not be hard to *implement* stereo panning, but it may be
quite
difficult to deliver something that everyone will like.
One idea I would like to see implemented is a pan/crossfade control
which
allows selection among simulations of the different curves in use on
the
physical world.
Brian Willoughby
Sound Consulting
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