Just got a Oberheim OB8, got some questions!

[adhmzaiusz]

Hey there,

I was wondering if anyone has a manual for the Oberheim ob8 they could possibly send me. The one available for download on this site is all blank pages when i open it, i think the files corrupt. Im particularly interested in the functions of the "page 2" option as my ob8 is the one without the screening of what does what. Any help would be great!! And if anyone has any nice tips they'd share on this too!

And one more thing...just out of curiosity, i just picked it up tonight for 1000 canadian, and its in pristine shape 8) . What's the going rate on these right now, because im pretty sure i got a sweet deal. It belonged to a guy who had it in a roadcase in his basement for 20 some-odd years who never used it!! when i saw it in the music store i thought it was some new synth that oberheim somehow came out with because it still looks brand new!!

thanks,

Greg

[clusterchord]

that's a phenomenal deal rest assured.


i couldn't source the user manual at first try, but i recall it has used to be online. all OB series manuals were always easily found. i did however find the service manual, which might come in handy in times to come: http://home.swipnet.se/cfmd/synths/companies/oberheim/

[fOZf8]

krikey the page 2 stuff drives me nuts. My buddy keeps all that scrawled in a handy studio notebook...he may have a manual...I can't be sure though...I doubt I'm helping much really. If it's got thee midi mod though, you're golden.

[adhmzaiusz]

thanks for the response guys, ive searched the web like crazy and cant find anything except that service manual. I admit though the keyboard did have problems... which are minor. there was a dead key but i just finished fixing it. Damn its easy to fix those, thats the 3rd synth ive fixed that problem on now. its always that rubber thing is folded and the contact is out of place. i had the exact same prob with my sh101 when i got it but fixed that in a snap. The other problem though is unfortunately voice 2 is dead i guess i need a 3340 cem chip(unless its an adsr chip dead maybe?). I see that curtis doesnt sell them anymore which is bogus . Well, at least the only page 2 thing i know how to do is turn off this dead voice at least.

If anyone else can help about the manual i'd be very grateful!!

[xpander]

i have the same OB-8 manual- it appears corrupted if you look at it with the Preview app (Macintosh) but is perfectly viewable using Adobe Acrobat Reader. it's the only file i've ever seen behave that way. so make sure you view it with Acrobat and nothing else.

i do have a hard copy, too, but it's a reproduction (but it is signed to me by tom oberheim!)

[adhmzaiusz]

i have the same OB-8 manual- it appears corrupted if you look at it with the Preview app (Macintosh) but is perfectly viewable using Adobe Acrobat Reader. it's the only file i've ever seen behave that way. so make sure you view it with Acrobat and nothing else.

i do have a hard copy, too, but it's a reproduction (but it is signed to me by tom oberheim!)

aha!

that was actually my first suspicion, that I should try acrobat to open the file(I work at fedex kinko's this should have been a no brainer) but alas i was too lazy to go download acrobat to try it out. (but for some reason i didnt mind looking for hours on the net for an alternative... figure that one out )

[WhinyLittleRunt]

The other problem though is unfortunately voice 2 is dead i guess i need a 3340 cem chip(unless its an adsr chip dead maybe?).

Yeah don't assume it's a voice chip because my voice 1 is faulty also and I had a pretty good tech send me a few CEM chips to try and it never made a difference. It will work for a little while and it gradually disappears. Probably something else on the voice card but I never cared to fix it; 7 voices is ok as far as I'm concerned. You can disable the dead voice in page 2; just double click on the chord/page 2 button. The first thing you notice is all the patch buttons light up solid. This represents active voices. Just click on the voice that doesn't work and the light will go out, disabling it. This way when you're playing you won't hit "dead spots".

[madtheory]

Isn't it possible to remove the voice card and send it for repair? If so, it might be worth trying lifting out the voice card and re seating it. Or is that only the OBX?

[adhmzaiusz]

Isn't it possible to remove the voice card and send it for repair? If so, it might be worth trying lifting out the voice card and re seating it. Or is that only the OBX?

yea im sure that is entirely possible, when i was fixing my dead key i tried unscrewing the voice cards (there are 2 pcbs screwed together one on top of the other which are about 10"x10") and i unplugged the ribbon wire which looks like a computers ATA hard drive wire and forgot to plug it back in, and it still played without the whole card plugged in. Mind you it was only 3 voices.

It may be easier to trouble shoot which chip is broken by swapping them rather than risk shipping the whole board though. When i get a chance im going to listen with only the problem voice active and see if i can at least hear the adsr in action or the filter going close to oscillation and i should be able to nail the problem. Funny thing i noticed about the filters on it though, is that all the filters go to different ranges of close to oscillation to full oscillation. i guess some semi-fixed resisters need some attention...

[WhinyLittleRunt]

There are 2 Pc boards inside with 4 voices each on them. They stopped manufacturing the cards seperately after the OB-Xa.
Just disable voices with the page two function until you find the culprit.

[adhmzaiusz]

Just disable voices with the page two function until you find the culprit.

Well, at least the only page 2 thing i know how to do is turn off this dead voice at least.

thanks for the advice, that was actually the only peice of info i could find regarding page 2 before as stated above!! I had the oberheim open today and i dont think i want to try removing any cems anymore because i bent the h**l out of one of the adsrs and almost bent the pins of it right off!!! i think i'll just find a tech to find what isnt working with the voice
i got the manual working though thanks! but its still kindof hard to see whats what because the resolution is small.

On the bright side, the dead voice adds to the arp sequences now, it adds a pause to certain beats that want to play the dead one

[radek tymecki]

Remember. When You open OB8 You have there red "button" with 8 mini switches. Look if they're all turned on. Also You can activate sounds in page 2 but this was mentioned before

i own ob8 so

Also. You can switch cards and see if they're really faulty!

[hfinn]

Also. You can switch cards and see if they're really faulty!

You can't on an OB-8.

[adhmzaiusz]

Remember. When You open OB8 You have there red "button" with 8 mini switches. Look if they're all turned on.

I didnt see any 'mini switches' inside of it or a red button... i only saw 2 test mode switches on the lid
where would i see these mini switches? on the voice boards? maybe its only on the newer ob8s

I already know which voice it is and where to find the voice on the pcb but still im not sure what it is..adsr..osc..filter....?
you cant swap the boards either because they are stacked one on top of the other and the bottom one has a volume plug that is only on the bottom pcb that plugs into the top. im now afraid of swapping the cems becuase i suck at removing them

[radek tymecki]

Also. You can switch cards and see if they're really faulty!

You can't on an OB-8.

yes you can. i own ob8 and owned ob-xa