Moog Music Forum

Hi guys, i'm new around here... first I would like to say that i'm very happy to have the association of so many Moog freaks (like myself:) especially in times like these.

I've been having some problems with my precious Memorymoog and even though i have an experienced technician working on it he's NOT a Moog/Memorymoog expert, so he's having a hard time diagnosing the problems... I would greatly appreciate any help i can get. Thanks!

Major Problem: "Brain Dead" (no sound or lights) This problem slowly became worse over the past few months... First it would just lock up every once in a while and i would just turn it off and then back on... a few weeks later, the lights and display started flashing and then it went completely brain dead.

Minor Problem: "Self Editing" The Memorymoog display would randomly show the current position of the Voltage Controlled Amplifier's "Release control" even though it hasn't been touched by anyone.

Any processor based analog polysynth is a very complex system to troubleshoot and the Memorymoog is one of the toughest.

To be frank, these kind of problems aren't easily solved over the internet. You're looking at an intermittent part that is bringing down the entire system, and finding that intermittent part is akin to the needle in a haystack.

You can start by monitoring the supply rails. Processors don't like fluctuations in the supply rail, and "self edits" kind of points to that.

If your Memorymoog power supply has the power transistors socketed, that is a known problem that is solved by removing the sockets and soldering the transistor leads directly to the PS board.

If the rails are good, you're staring at the intermittent component problem. You're talk 100+ potential failure points. I can't offer much beyond that.

MC,

Thanks for the advice... I'll be sure to post the solution.

Good news! The Brain Dead problem has been solved! It was the buss cable between the ops panel and the main pcb.

I'm also thinking about having the power supply rebuilt... Can anyone give me a quick outline on how to do this? Or Is it really necessary on the newer
Memorymoog Plus models serial # 2700?

Good to hear your tech found the problem, good luck with the rest.

It probably would be a good idea to at least have the tech recap the power supply, figure it is at least 25 years old. Rebuilding may also be worth looking into for more stability. MC would know more . There were a lot of Memory Moogs that were retrofitted in the filed to be MemoryMoog Plus’s, ( Mine is one of them…which is also dead right now SN is in the low 2000) I also have a regular MM (upper 1000’s) that has it’s share of problems. Too long of a story to say why I haven’t fixed either or both yet But I will. If they have had all the service updates done to them, they are pretty stable . I don’t think I would gig with it or move it around much though. If you do a google search al the service updates should be available.
I don’t know at which serial number the Plus were released. The MM is still one of the best poly synths from the 80’s it will do everything from quite pad, to tear a brick wall down. The Arpegiator was pretty cool on it and while limited the sequencer had it’s uses. I never had a chance to try the mono sequencer track that outputted to the CV outs with an external synth like the Mini Moog. Tuning the cards was always a “treat” 18 osc’s three adjustments each .

Enjoy

I want my tech to rebuild the P/S... He asked me if there was an article on-line that describes the procedure... I haven't found one yet.

I've had my Memorymoog Plus for the past 12 years and it's only been down twice, and i've never had any tuning problems, either. But it has all the updates, so... The first time it went down i had to ship it out to Wes @ analogics, and that cost me about $800 total... I can't do that again, so that's why i'm trying so hard to help my local guy figure it out.

Maybe you should send yours out to Wes! He's very confident about working on the Memorymoog, and you can't say that about many... Even Kevin is scared of them:D

Yeah, I love my MM more than any synth... I've made some great music with it, but it scares me when it stops working.

1

I've thought of sending it out to Wes, but would rather find someone local first and not ship it some where. I had a guy but he moved. Where are you located ?

Brian G wrote:I've thought of sending it out to Wes, but would rather find someone local first and not ship it some where. I had a guy but he moved. Where are you located ?

I know what you mean... I'm in Florida so when my MM came back from Wes in Ohio the flight case was pretty badly damaged, i can only imagine what it went through. If you can afford it, Fed Ex overnight or 2nd day is the way to go.