[sdiy] Oberheim OB-Mx schematics and ROM dumps now up

[Aaron Lanterman]

On Sun, 19 Mar 2006, harrybissell wrote:

> stephengoldin.com/gibson/technohick01.html
>
> Read it and find out. What a cluster-fvck :^P   LOL

Yup - the annoying thing in working with the OB-Mx is you can tell it's 
unfinished... and just imagine what Buchla could have done if he hadn't 
been straighjacketed into using the parts that had already been 
purchased.

I was going to link to it, but decided not in case Gibson some sort 
of publicity cops out there looking to beat up people who gave them 
negative publicity.

Oddly enough, it's the OB-Mx that started my interest in the subtleties of 
analog design, eventually leading to me joining this list, and eventually 
leading to me doing the synth special topics class I'm doing now. Everyone 
complained about the sound of the filters on the OB-Mx - but as you see 
that really is a transistor ladder, and it really is a state variable 
filter - the one unique thing is the use of SSM2024s all over the design. 
I got to wondering why some filters sound different than others, which 
lead me to wondering, which lead me to wondering...

- Aaron

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