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Re: OB-SX voice board

2007-03-28 by analogback

thanks for the info Peter, i have some of ken Stones boards for lfos
and voltage generators. building it completely modular with a jack
panel that could interface with other modular gear would be the go. i
agree, its quite a job but i will have a shot anyway!  i have done a
lot of synth modifications so i'm confident with that, was just hoping
someone who may have done this particular project before would chime
in with any dos or donts!
greetz

--- In oberheim@yahoogroups.com, ogusa@... wrote:
>
> 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
> >> >
> >> >
> >>
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
>

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