Mixer dynamics project?

[bubba_b]

Right off I'd just like to say I realize what an expansive AND expensive undertaking this could be, but I'm still curious as to just how difficult it may be and if anyone has an idea on where to start. With that, here's my idea:

I'd like to install a series of simple (emphasis on the simple) compressors into an analog console, one on each channel, sorta like the big-boy consoles have. Not looking to go too big on luxuries like threshold and make-up, or even attack 'n' release on this thing. I'm thinking just one small pot (either find a blank spot and install a new one, or "sacrifice" an aux), make that a ratio and set the circuit for auto attack n release and make-up. Obviously, the PCB would have to be very small to fit in the channel (I'm thinking not much bigger than a 2520 or Melcor opamp PCB) and it'll probably have to be FET (assuming here?) to be small enough. Maybe optical, too?

Ok, so smack me if I'm dreaming too big. I think it's a cool idea, and if someone comes up with a good enough design and can be implemented into almost any console, you might have a nice little business on your hands selling PCB's and kits in the dozens per order.

 

[VacuumVoodoo]

Would a "One Knob Squeezer" based on chips from THAT Corp fit the bill ? The link is to a PDF file.

 

[StephenGiles]

Possibly a "simple" compressor would amount to a useless compressor, but a "What Compressor" would perhaps fit the bill. Simply connect it up and forget about it.
Stephen

 

[StephenGiles]

I think a What Compressor may fit the bill here, it's not fussy on opamps and of the switch on and forget about it variety.
Stephen

 

[bubba_b]

Thanks, guys. I was looking at the THAT one knob squeezer and it looks like what I'm lookin' for, but I would like to try an optical, as well. Any schematics for an optical floating around?

Viitalahde,
The console(s) I'd be looking to put these in are an Allen & Heath GL3300, possibly a GL4000, a Soundcraft Ghost and maybe a Crest GLX (I think that's the right model; 52 channel LCR console, 8-9 years old). For sure the A&H, the others are maybes. The A&H and Crest are used for live and the Ghost for recording.

p.s. I've got a SMPro TB-202 that has a one knobber and it's optical. Sounds decent, too for such a cheap channel strip. Maybe I'll tear that sucker open and see how it ticks.

 

[StephenGiles]

[quote author="Viitalahde"]Opto compressor.. Makes it possible to do the one-knob operation that even sounds good.

What compressor would probably do, but you need to re-design the PCB's. What's the console you're thinking here? Grab the service manual and you might find out you already have the I/O buffering there. Then - just a vactrol, sidechain and the knob. [/quote]

.....much quicker on veroboard!
Stephen

 

[Mendelt]

If you have a mixer with enough headroom per channel maybe you won't even need a squeeze knob. You just set the amount of compression by driving the compressor harder with the gain knob of the channel. That way you can have an extra control (ratio or combined attack/release)

Maybe you can make the ratio go up as you get further above the threshold so you can turn the compressor into a limiter when you drive it really hard.