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WIGGLING 'LITE' IN GUEST MODE

Oberheim EIGHT
MUFF WIGGLER Forum Index -> General Gear Goto page 1, 2  Next [all]
Author Oberheim EIGHT
daren
Has anyone used this thing? I just ran into it at a studio my friends are recording in last night. This one only has seven voices. The eighth voice has been replaced by two mini-sequencers!

Anyways, I'd like to know if anyone wants to share their experience. I'm not even sure if they'll let me play with this beast since they are paying the studio on a per day basis.
chromium
An Oberheim eight voice like this?

http://www.vintagesynth.com/oberheim/8voice.php


If so, there are a couple four voice demos here to give you an idea of the sound, and how the programmer interacts with the SEMs...



daren
Yup...that's the one. It's quite literally a beast in person! Hopefully I'll be able to get my hand on it today and record the experience!
chromium
Nice- that'd be fun to spend some quality time with. Been wanting a four voice for a long time- someday...
bastille
Four voice is second only to the Tom Waits Bosendorfer on my list of most coveted keyed instruments.
MindMachine
Grew up with a TVS 2 voice w/ Minisequencer. The unit you have access to is awesome. Just figure out which SEM's the MS's are routed to and then tune the other SEM's as a huge chord and have at it. That is the simple starting point I can think of. Those Minisequncers are awesoem w/ an SEM.
chamomileshark
One word "Holy Fuck" Ok that's two but I've temporarily lost the ability to count.

Any chance of a video/ samples. The Four Voice is already huge, that thing must have it's own gravitational field.
phono1337
the second video posted is the one i repaired, i used to work there.

what i can say is they are very high maintenance, i've worked on three of them in total, always some shit going wrong, but then they are from '76
chromium
phono1337 wrote:
the second video posted is the one i repaired, i used to work there.

what i can say is they are very high maintenance, i've worked on three of them in total, always some shit going wrong, but then they are from '76


Nice work! Sounds great in the video, and I liked that video especially since I've never had my hands on a programmer- and I enjoyed seeing how it interacted with the SEMs in real time.

Did you notice any commonality in the failures of the three units? Or was it just the usual suspects dying of old age... Just curious for when I am poised to go hunting for one. I've been temped by a couple of units that were being parted due to failures, figuring I could ease into it slowly ($$) adding SEMs as funds permit. I don't do repair professionally, but I take care of my own... and I'm brave (read: foolish) enough to attempt a project of that magnitude. hihi
chamomileshark
It's one of those machines I prefer to admire from afar even if I had the money. Unless I had the money to have a tech permanently on staff.
chromium
chamomileshark wrote:
It's one of those machines I prefer to admire from afar even if I had the money. Unless I had the money to have a tech permanently on staff.


Maybe my OB-8 has conditioned me hihi Man what a marvelous pain in the ass that beast is. Maybe just mine, but damn - can't count the number of times I've been in and out of that one. But I still love it.

Love hurts. MY ASS IS BLEEDING
phono1337
chromium wrote:
phono1337 wrote:
the second video posted is the one i repaired, i used to work there.

what i can say is they are very high maintenance, i've worked on three of them in total, always some shit going wrong, but then they are from '76


Nice work! Sounds great in the video, and I liked that video especially since I've never had my hands on a programmer- and I enjoyed seeing how it interacted with the SEMs in real time.

Did you notice any commonality in the failures of the three units? Or was it just the usual suspects dying of old age... Just curious for when I am poised to go hunting for one. I've been temped by a couple of units that were being parted due to failures, figuring I could ease into it slowly ($$) adding SEMs as funds permit. I don't do repair professionally, but I take care of my own... and I'm brave (read: foolish) enough to attempt a project of that magnitude. hihi


well the problems were certainly due to age, everything from blown opamps to bad caps. Most of the sem parts are still available at least.

The main issue with the programmers are they have (iirc) 4 custom oberheim ic's, now while ive never seen any of those die, if they do its going to be very hard to source replacements for them.
phono1337
chamomileshark wrote:
One word "Holy Fuck" Ok that's two but I've temporarily lost the ability to count.

Any chance of a video/ samples. The Four Voice is already huge, that thing must have it's own gravitational field.


its truely huge if you have the 8 voice love thats bascially the same as the four voice with 2 extra programmer cards and 4 sems in a flight case connected by the rear port
chromium
phono1337 wrote:
well the problems were certainly due to age, everything from blown opamps to bad caps. Most of the sem parts are still available at least.

The main issue with the programmers are they have (iirc) 4 custom oberheim ic's, now while ive never seen any of those die, if they do its going to be very hard to source replacements for them.


Yeah that's exactly what I was curious about - those custom Curtis chips for the VC envelopes in the programmer. I had saved this photo off the net of them- the ones with the yellow labels:




Wonder if someone were ambitious enough if they could hack around these by routing the signals from the DAC to a custom board with a non-proprietary VC envelope solution? hmmm..... Anyway, no doubt that servicing those would pose a huge challenge indeed.
phono1337
yeah those are the ones, if you pull back the labels they say oberheim on them.

Though as i said i've never seen those fail, the ones that do pop a lot are the central ones above the massive row of caps, luckily they are easily replaced. Getting them off the boards is pretty tricky, its a cut out job if you dont want to trash the pcb.
fivesteppath
MY ASS IS BLEEDING i want one now.
daren
Hm...jammed on this. I couldn't figure out how the Mini-Sequencers were routed. Three of the voices were connected. The top and bottom halves seemed to be very independent of each other. I only had headphones to use and each half had its own output.

Sounds pretty great. I wish it had more than Saw and PW waveforms. The sequencers are great too...you could sync them or have them run independently.

I couldn't figure out the programmer...loading or saving.
dougt
My Four Voice has a mod that gives you triangle waves on both VCOs as well. The programmer and poly key assigner have probs though. For some reason it only sees the first 2 SEMs.
daren
Yeah...I couldn't figure out how to get the "poly" out of the keyboard. It was normal mono. But, the mini-sequencers are great. I love being able to change the step lengths on both and have them sync up, producing nice harmonies that lasted more than the eight steps.
chromium
daren wrote:
Yeah...I couldn't figure out how to get the "poly" out of the keyboard. It was normal mono. But, the mini-sequencers are great. I love being able to change the step lengths on both and have them sync up, producing nice harmonies that lasted more than the eight steps.



I enjoyed this TVS-1 demo with the mini seq:



Those sequencers do look like fun!


I swear, these threads always get me all spun up - already been strategizing on what gear to let go of to build an FVS fund Dead Banana

BTW- thank you for sharing your experiences, phono. Always helps to know a bit more about what I'm signing up for in the long term...
Curtischip
I've have a Four Voice which I adore, I use a roland mpu 101 for poly midi mmm yummy, unfortunately its in bits atm mo so if you want some pics of its guts let me know and I'll post...
it got sick awhile ago, then progressively worse over the course of a week. I've not had the time to really dig into it (not that I'm tech) just looking for obvious faults, until now its not given me any probs (10 years or so in my possession)
I think the battery might be the cause of the probs, can anyone suggest a replacement pls... ty

has anyone built a patch panel?

Soapbox imp, its one of the best priced vintage synths.
jupiter8
8 voice ? Too limited. 16 voice at least or nothing.
chromium
Curtischip wrote:
I've have a Four Voice which I adore, I use a roland mpu 101 for poly midi mmm yummy, unfortunately its in bits atm mo so if you want some pics of its guts let me know and I'll post...
it got sick awhile ago, then progressively worse over the course of a week. I've not had the time to really dig into it (not that I'm tech) just looking for obvious faults, until now its not given me any probs (10 years or so in my possession)
I think the battery might be the cause of the probs, can anyone suggest a replacement pls... ty

has anyone built a patch panel?

Soapbox imp, its one of the best priced vintage synths.



Well I'd never refuse a chance to see more photos of the insides, if you're willing! w00t we're not worthy


Here's a site with some photos of the programmer, specifically as it relates to replacement of the battery - buried a few boards deep...

http://www.siliconbreakdown.com/ob3.html


There are schematics posted here if it helps you in tracing out your problem (grab the big zipfile, as the link to the programmer schematic by itself is broken):

http://www.synthfool.com/docs/Oberheim/oberheim4and8voice/


There's a bunch of old 4000-series CMOS in there that I would probably hone in on if there were problems in the programmer or kbd controller. Also like phono mentioned- old caps and opamps are usual suspects too
Curtischip
Hey thx Chromium for the info, thumbs up
re battery, Kevin states he not sure if thats correct battery and should be replaced with the same type, the battery I removed is from the middle ages, its made with mercury, I've had no luck finding one so maybe I'll try the 3v lithium. pics on the way!
chromium
Curtischip wrote:
re battery, Kevin states he not sure if thats correct battery and should be replaced with the same type, the battery I removed is from the middle ages, its made with mercury, I've had no luck finding one so maybe I'll try the 3v lithium. pics on the way!


Yeah the battery in those photos looked like a modern replacement. If I'm seeing correctly (big if), it looks like there's a battery in the center part of the programmer schematic marked as 4.2v(?):



Hard to tell given the scan didn't pick up the writing there very well...
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