Hey Fellas…
Nice to meet you all. My name is BlacKHawK. I joined your forum because I am hoping one or some of you might help me with some questions about an Opus 3.
I’ve had this little synth for years and years and it’s served me well. A couple of years ago I put it in storage with some other gear while I kind of dropped out for a while. Well, I’m back in the world now and I am setting up my studio again. I discovered that not only did I put my Moog in storage, I also provided a cool little home for a mouse or two. I discovered this after I lost the ‘B’ keys and took the cover off to find the problem. Inside was a huge rat’s nest built on top of one of the circuit boards.
It’s cleaned up now, no more mice. However, there is a lot of corrosion on the circuits, ammonia from mouse piss I’m sure. Amazingly, it still plays, except for the ‘B’ keys. I found the piece that corroded off the board which I believe is responsible for the ‘B’ keys not working. But, why put it back on a corroded board?
I guess that’s the long way around to asking if any of you know where a fella can find salvaged parts for these old synths? I should have just posted the question, but I thought the story made it more interesting.
Thanks for your help,
BlacKHawK
Some very good links, including sources for restoring a Moog. IMO it’s best to send it and have it serviced by someone who knows what they are doing, even if a little more expensive. Amongst them, Archive Sound and FM Music are both good:
http://www.till.com/articles/moog/
Hey BlacKHawK. I’ve just finished fully restoring an Opus 3 myself. No mouse piss though thank God, but I did of course have to contend with the dreaded black foam!!!
I am by no means a hardcore synth tech, but I do have the technical manual and schematics for the Opus 3 if you are interested (see other postings for details). Also, reproductions of the sliders and switches are available on ebay from the seller ‘chipsforbrains’. This is what I did - totally cleaned up the circuit boards and put on all new switches and sliders! And a general cosmetic cleanup from top to bottom, including new audio jacks and a few other things like that.
As for other random spare parts I dunno, depends just what it is obviously. If it’s just a simple resistor or capacitor it is probably something standard that you can get from electronics stores once you know the specs? The schematics will at least let you know what you need. But I am guessing some of the parts on there are fairly specific or harder to find. In which case, someone else might know a good place for old bits and pieces from wrecks?
Anyway, take it easy and all the best with the restoration!
Ok, so i had a similar problem with mouse piss in my opus 3…and i’ve restored a decent portion of the synth so far but oh man…the chorus board is shot…and gross…and im pretty sure its the only PCB in the thing that wasn’t manufactured by moog (and if so, it’s pretty shotty).
I’ve pretty much given up because i can’t, for the life of me, find a NOS top octave frequency divider chip for that synth…they are nowhere to be found. I keep waiting for chipforbrains to sell them but i don’t think he will and i can’t let this thing sit in my closet anymore!
I keep thinking how foolish i was to bid 300 bucks on a non working opus 3!!!..but i was really hoping i could just open it up and find that the fuse was blown or there was just a fried opamp in the amplifier section…but no…it’s those dirty RATS (literally)…
So hey, if you ever wanna buy mine for parts…lemme know…i’ll throw it up on ebay or something…
what a shame…i spent so much time cleaning that thing out & washing poopy circuit boards
BlacKhawk,
I’m also by no means a synth-tech, but the problem you’ve described about the “B” notes sounds like an oscillator divider chip problem. There are probably 12 of these chips in the Opus, one for each note, and on your Opus, the one for the Bs needs to be replaced.
I’ve read that this is a common problem with Moog MG-1s (which I think might use the same divider chips as the Opus), and that the chip is still in production(?), or at least still available somewhere. I remember someone saying it was a $25 chip, which is pretty expensive, but well worth it to get your synth fully functioning.
If this is the only problem with your Opus, I wouldn’t think it’d be worth it to scrap the whole PCB board (as revolting as Mouse fecies may be…). To get a new board, you’d have to buy a whole new (non-working)Opus-- which would probably come with additional problems and end up costing nearly as much as a whole new working Opus.
It’s probably possible to clean the PCB board, if need be. Otherwise, maybe just try to address that one problem and see if everything else is OK.
Some internet research on Opus and/or MG-1 Osc Divider Chips will probably turn up some useful info.
Or, you might also try looking at Kevin Lightner’s ‘parts for sale’ page for this divider chip (or maybe even politely ask him via e-mail if he has this part ):
http://www.synthfool.com/store/
And ‘chipsforbrains’ e-bay store/e-mail…
What was it with divider chips on vintage string synths? I had a Korg Delta which died for the same reason and after months of searching I finally sourced the chip but the guy wanted around £80 for one chip! Ended up flogging the delta on ebay ‘spares or repair’ for £50 ish. It really would put me off buying another string synth from that era as they all seemed to use the same design principle.
Senso sometimes gets them in, and he won’t rip you off (too much):
http://www.vintageplanet.nl/index.html
Doesn’t look like he’s got any at the minute but it might be worth a quick email.
I am the ardent defender of all things divide-down. : )
I had the F# go out on my Korg PS-3100. I was told by my tech and subsequent techs that Korg had the good sense to use basically off-the-shelf parts, and that these parts are far more readily available than some of the proprietary parts used in other synthesizers. My tech at the time seemed to have trouble finding the divider I needed… but my tech was also a busy person. The only place he found the part was at some bizarre place in Canada run by a guy you had to be careful not to offend. He wanted some ridiculous amount for the part. So, a friend of mine directed me to a electronic parts website on the net. They were having a sale on the part I needed… very cheap. I ended up buying a bunch of them in case any more dividers went out on the PS-3100. I wish I could remember the company name! They were small, but had a lot of parts and were very friendly. I’ll see if I can dig it up.