OBERHEIM SYNTH

Each of the connections like PWM, ENV etc. are voltage control inputs.  
THe voice board does not produce envelope or control voltages, they  
were created by the CPU.

You face quite a challenge YOu would have to build at leat 2 envelope  
generators  and LFOs, as well as several static voltage generators  
(pots), get voltage control to the envelopes and LFOs and set up a  
routing matrix. Even on the classic monosynth, the architecture is  
"normalized" but there are switches for various CV routing otions.

Plus much of the Oberheim "sound: came from the many control  
possibilities (Env mod PW 1 with delay etc). If you want that sound,  
you are going to have to build half of a a full modular system to  
support the module.

Anyway, unless you're a analog synth designer or advanced hobbyist  
(like myself), you'll never get it to do what you want.

Sorry,

Peter

Quoting analogback <gehayman@...>:

> thanks for the reply Jeffrey,
> i found schematics and voice board connector info today, apparently,
> the board was from a blue obsx which is supposed to have the same
> voice card as an ob xa. but a few questions remain!
>
> i have a midi-cv converter and +15v -15v & -5v power supply (required
> voltages)
>
> there are a few connector ins/outs that are labeled but not
> immediately obvious to me so i will try to get more info!
>
> if anyone with knowledge of these machines would care to take a look
> at this picture, perhaps it could help me determine the less obvious
> connection points?
>
> http://i133.photobucket.com/albums/q55/neonleg/obxapinout.jpg
>
> thanks!
>
>
>
>
> --- In oberheim@yahoogroups.com, Jeffrey Nelson <nelsonj_sce@...> wrote:
>>
>> You will need to power it up, and then supply it with
>> a gate and CV.  A good place to start is a Midi to CV
>> converter.  You can get them off of Ebay around $75.
>>
>> The problem will be the power supply, you will likely
>> need +/- 12V and +/-5V and others perhaps.
>>
>> The other problem is that you need to provide voltages
>> for all of the envelopes, VCF filter and res...
>>
>> Finally, you need to build an final output stage for
>> overall volume control.
>>
>> In short, it can be done, but it won't be easy.  Not a
>> simple project.  Get a schematic first.  Good luck.
>>
>>
>> --- analogback <gehayman@...> wrote:
>>
>> > hello! i have an obsx voice board that i would like
>> > to try and modify
>> > in order to use it as a standalone monosynth.. does
>> > anyone know if
>> > this has been done before? if its possible?
>> > obviously the boards
>> > connector info would be a great help as well!
>> > any info appreciated as i've scoured the net to no
>> > avail :(
>> > greetz
>> >
>> >
>>
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