haha nice end quote!
Ok. here we go. this should be a fun one that i will attempt to explain and not get you lost in the process!
First though kinda forget the whole matrix part that you mentioned.
Ok so here we go on the subject of
VCA's (
Voltage Controlled
Amplifier)
First thing is
VCA's do not pass any audio Whatsoever.! End of story.
A
VCA and a group are similair BUT NOT the same. Moving on.. a
VCA is more or less a remote control for a
channel or set of channels. (for bitechs kinda think a
submaster.. sorta)
So here we go scenario, lets start with a group first.
So we'll say we have some female actors and some male actors and we want to group the male actors and the female actors into two seperate groups. When we assign them to a group respectively we know that when we bring up that group
fader and then
send it to the stereo bus if it's not already sent there it increases the amount of volume from the amount that you already have up on those channels.
Now, here's where it can get tricky in similarities. If I have the first gurlz mic up and sent to the group as well I'm rockin and rollin. But, what happens if say for instance I take her
channel and unassign her from the stereo mix but leave her group assignment up and turned on? Well, she's still there it is just decreased by a relative amount of dB. (10dB i believe) This is because she is being sent to a group bus and then that group bus is PASSING SIGNAL to the stereo bus solely(as well as its respective o/p's). Ok, now I made that
point to say that some of us know tricks of using group inserts for this situation, some recording audiophiles mix this way, and that is where the two Merge and become similair.
A
VCA on the other
hand is solely just a remote control for
channel(s) on your board, as previously mentioned. So, back to our scenario we have the gurlz and the guys. Say for instance I take one of the gurlz and i assign her to my first
VCA. (This is all assuming that some of us know proper
gain structure and little beckys
channel is at unity.) With her
channel at unity and assigned to the first
VCA and that
VCA AT UNITY as well you should here no
VOLTAGE gain difference like you would a group. Now, as you bring that
VCA down you will hear her slowly go away(if you will think that as this the first
VCA fader is being pulled down her
channel strip
fader is being pulled down at the same time and same
voltage respectively and no its not literally moving with the
vca this is just an example, moving
fader VCA's those that know the D5 and digital consoles

) As you bring the
VCA back up to unity, then so does that
channel become respectively. As well as if you go above unity, then that
channel strip or strips are going above unity as well.
Ok, so if your not totally lost. Lets recap!
VCA's only remotely control
voltage of
fader(s) Whereas, groups pass
voltage and and add
voltage as channels are assigned. One of the big reasons that mix engineers prefer
VCA's is it allows you to use groups for other things(i.e. go figure it out. lol) They allow you to control similair areas of your show (band, chorus mics, lavs., and so on) without having any
voltage running through them, that's handy if the
VCA section decides to take a dump.
Ohh, and found a little furthur reading that may help, may make you get lost on the internet from AandH.
http://www.allen-heath.com/US/ViewProductDownloads.asp?search=Mixing Live With VCAs
Anyhow, I hope none of you got lost in this big ramble. If you have any questions don't hesitate to ask.
Oh. and if any of you wonder y i say gurlz with a z it's because the performers use to be "CurlZ GurlZ" labled on the board. lol