SSL VCA <--> computer communication

HI!
Anyone knows how a SSL 4k VCA deal with the computer?
I know that for each 8 channel there is a 50 pin ribbon cable going to the computer...
Anyone knows the pinout?

My dream is to build an interface to controll vca's by an external system and shut down the ssl computer. :

While anything can be done, it is re-inventing the wheel... you need to get a hold of a console & computer manual, it is all in there

Do you have TR or Ultimation fitted?
Looking at the Analog In and Out card schemos will indeed be the first step.  Then Lights and Switches for mutes.
I would certainly be easier to implement now than when originally designed.
 
Mike

No Ultimation, just VCA. Don't mind about TR just want to make mixing easier (and save power switching off the computer).
Unfortunatly I don't have the computer schematics.  :-[
I hope that the console send to computer analog card a voltage for fader position and analogue card output send it back to the console. I would be easy...  :

If you just want local control of VCAs simply install jumper plugs at the console end where the 50 way ribbon cables from the computer plug in. Use a 10 wide piece of ribbon cable, crimp into a 50 pin connector to connect  pins 31-40 to pins 41-50.

I know that but i would like to use automation.
My project is to use a cv to midi converter to control vca from the daw.

Nickos said:

I know that but i would like to use automation.
My project is to use a cv to midi converter to control vca from the daw.

Click to expand...

Would that be a 7 bit resolution or higher? My vague memory says the SSL computer had 10 bits resolution. As far as I remember the computer basically reads the control voltage and either puts the same value out again for 'live' fader control or writes the formerly stored values back, which would be automation. You could work that out with a console manual alone (you got that?), you basically need the control voltage send and return. Basic reading / playing back might be relatively easy to achieve with midi and a sequencer. It does get difficult with trimming, overwriting etc.

Thinking about it, weren't cuts 'encoded' into the control voltage? Something like 0-5 V for fader movement and +10V for cuts (total guess os values here)? You could easily measure this. Even without the console manual you could try to work out the pinout if you have the computer bypass connectors which replace the ribbon leads for those who don't have a computer. You can see which pins are bridged, just measure the voltages there and find the control voltage when you move a fader. It is all logically arranged, if you have the pin for fader 1 and fader 2 of a bay you will know the pinout ;-)
Also with a computer attached you could measure the pins of the ribbon connector, but you will obviously find 2 pins for a fader being moved - send and return. If you unplug the computer, the send should still be active, so you would know which is which.

Sorry for being vague, it's been too long ago for me... But maybe these thoughts get you going?

Michael

It will work for sure... before the next mix I'll check for voltage values.
Trimming and overwriting would not be a problem, every software can handle midi automation data.

Thank you!!

Nickos said:

My project is to use a cv to midi converter to control vca from the daw.

Click to expand...

Keep us updated on your project. I would love to store my ssl automation data right on a midi track in a daw!
Dan

dustbro said:

Keep us updated on your project. I would love to store my ssl automation data right on a midi track in a daw!
Dan

Click to expand...

Do you have the computer and console schematics? can you send me the pages about vca and computer analog interfaces?
Thank you

Nickos said:

Do you have the computer and console schematics? can you send me the pages about vca and computer analog interfaces?
Thank you

Click to expand...

Not a prob. Its gonna take me a bit of time to scan the manuals, so I'll send them as soon as I can

All you need is on page 1 of section 5, and the pin-out of the 50 way cables to the computer (as I stated before, pins 31-50 are 8 channels of send, 8 of return, ground and master fader, where used). It is 0 to 5 volts (I think I remember correctly that 5 volts is audio level all the way down, same as a cut).
Nothing more to it I can see, AtoD & DtoA are done in the computer.
Interested in your progress, it would be nice to have an alternative if these computers ever actually die.

This will take care of the automation. Have you thought about Total Recall yet? Maybe a MIDI sysEX dump like SSL does on the X Logic rack?
http://www.solid-state-logic.com/music/xlogic%20x-rack/

Yes!  8)
Thank You very much!!

nielsk said:

All you need is on page 1 of section 5, and the pin-out of the 50 way cables to the computer (as I stated before, pins 31-50 are 8 channels of send, 8 of return, ground and master fader, where used). It is 0 to 5 volts (I think I remember correctly that 5 volts is audio level all the way down, same as a cut).
Nothing more to it I can see, AtoD & DtoA are done in the computer.
Interested in your progress, it would be nice to have an alternative if these computers ever actually die.

Click to expand...

yeah but if the computer does die don't you loose that a/d-d/a?

Those AD-DA converts the voltage from VCA's into data for the computer.
There isn't any other purpose for them...