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WIGGLING 'LITE' IN GUEST MODE

Moog 984 4 Channel Mixer
MUFF WIGGLER Forum Index -> 5U Format Modules Goto page 1, 2, 3, 4  Next [all]
Author Moog 984 4 Channel Mixer
dingebre
I thought this module would be a fun clone. I did it as a 5U module following the Synthesizers.com panel specification. It's big for what it does, but I think it's comparable to the Moog panel. Mine is 5 units wide. You'll see I use 1/8 inch jacks for the inputs because this is going to sit in my Synthasystem racks, and they are all 1/8 inch. I used 1/4 jacks on the output to make it easier to connect to my audio interface. I added an OpAmp in the output stage that can be switched in or out with a DPDT DIP switch, or hard wired in or out so I can bring the output levels up to the levels in my Synthasystem. Otherwise, it is a faithful reproduction of the original.

I changed the panel somewhat from the original MOOG panel but not dramatically.

It takes 4 PCBs, but they are pretty simple. If anyone is interested in more info or you want to buy some PCBs, send me an email or PM. Unfortunately, there is a lot of wasted space on the PCBs and so the price per PCB is a little jacked up, but I think in quantities, they won't be too bad. There aren't really any odd parts in it, three 2N2926 transistors, but there are several cross matches and Cricklewood or Dalbani/Nikko have them in stock. There are a couple of odd value electrolytics, but you can just get the closest value and it should be fine. I laid it out to use Alpha PCB mounted pots, but others may fit.

I need to build first it to make sure it works, but the simulations I ran seem fine. I just ordered a panel and prototype PCBs. I should have it built in a month or so.

As soon as I'm convinced it all fits and works, I'll post the schematic and FPD panel file.

David
robotmakers
The 984 matrix mixer is an extremely cool piece that can either be superfluous or necessary, and will appeal to some and not at all to others. For me, I run everything through it all the time. Others will see it as space wasting for a four input mixer. My system, which is just one snowflake in this tundra of modular variation, is dedicated to four voices set up to minimize re-patching and is split into four front-ends (largely VCOs) and four back-ends (largely EGs and filter/VCA chains). Four sources go into the 984 mixer and can be sent to any or all of the four modifier chains. This allows polyphonic or arbitrarily complex monophonic setups without repatching. A bunch of other matrices handle CV/GATE allocation and modulation. In addition, because I run a mixed Moog (1.3v peak to peak) and modern (10v peak to peak) system, the 984 helps me normalize levels so things don't get unintentionally overdriven.

I like what David did with the four outputs - moving them to the right on the panel greatly clarifies what's going where.

Best regards,
Roger
NYMo
Rodger...do you have a link to a pic of your modular please ?

Cheers
robotmakers
NYMo wrote:
Rodger...do you have a link to a pic of your modular please ?


Glad to oblige. It's actually grown a bit since this pic was taken, but here's a nice shot that was used in an article on the "Create Digital Music" site a couple of years ago. The 984 is visible in the lower part of the Moog rack.

Cheers,
Roger

dingebre
Thanks for the kind words. Very nice setup. Thanks for sharing the photo.

David

robotmakers wrote:
The 984 matrix mixer is an extremely cool piece that can either be superfluous or necessary, and will appeal to some and not at all to others. For me, I run everything through it all the time. Others will see it as space wasting for a four input mixer. My system, which is just one snowflake in this tundra of modular variation, is dedicated to four voices set up to minimize re-patching and is split into four front-ends (largely VCOs) and four back-ends (largely EGs and filter/VCA chains). Four sources go into the 984 mixer and can be sent to any or all of the four modifier chains. This allows polyphonic or arbitrarily complex monophonic setups without repatching. A bunch of other matrices handle CV/GATE allocation and modulation. In addition, because I run a mixed Moog (1.3v peak to peak) and modern (10v peak to peak) system, the 984 helps me normalize levels so things don't get unintentionally overdriven.

I like what David did with the four outputs - moving them to the right on the panel greatly clarifies what's going where.

Best regards,
Roger
NYMo
Wow we're not worthy Serious electronics !
What system is "abandon normal instruments"?

Cheers
robotmakers
Evidence of a serious addiction! That white faced unit is something I built a very long time ago with 1980s vintage CEM 3310, 3320, 3330 and 3340 chips. It was originally meant to be 6 voice polyphonic, hence the duplication of functions. I quickly gave that up and used it as mono synth. Here's what it originally looked liked perched above a Hammond M3 back in the day.

Cheers,
Roger

NYMo
Thanks Roger..nice !
(Ah..I think I understand now..the above picture is a paen to Emerson)

Cheers
dingebre
Well, it's done and I love it.
JohnLRice
dingebre wrote:
Well, it's done and I love it.
Great job! thumbs up Stereo mixing (at least) is the way to go with modulars! 8_)
dingebre
Thanks smile
Dave Peck
Ooooh! Got a picture of the back of it? I wanna see it all bare nekked!
dingebre
I'll get some more photos up tomorrow.

David
dingebre
OK, here are some more photos of the front and back. 4PCBs, board mounted Bourns pots, I use a MOTM style connector and regulators to get the +12/-15 volts I need.

I'm including a couple of photos of my "vintage" modular so you can see how the 5U works with my other euro stuff. I know this is a 5U format, but I think this is ok since it's a mix, If not, I humbly apologize. Primarily a resurrected Steiner-Parker Synthasystem using the original designs and all original components (thank you for all your help Nyle...). There are some DOT COM modules in the top two cabinets with a CP3 4 input mixer clone I'm working on and a space for an ordered COTK phase shifter. The bottom two cabinets house the Synthasystem modules with a MOS-LAB low pass filter clone with a space for a MOS-LAB high pass filter which is on order on the left side. The right side has more Synthasystem modules and my clone of the Moog dual trigger delay, reverb, and a 914 fixed filter bank clone. The 914 is working but I'm waiting on the latest and hopefully last PCB sets. The bottom row has a COTK frequency shifter clone and my 984 clone.

There's a Tinysizer on the right side. The controller is one of Roger Arrick's new midi controllers which goes into a Steiner-Parker Duophonic keyboard clone which takes the midi and drives a set of reed relays which perfectly mimic a bus style keybed and divider to drive the Steiner electronics.
Dave Peck
Very clean build, well done!

.....Okay, now I'm really curious about the Steiner-Parker stuff in your synth. Please consider posting about that in the general synth subforum, maybe in the 'show us your synth' sticky thread!
dingebre
******************************
Edit 7/28/2015:
My website has a new address:

www.analoguerealities.com
******************************


Ill post more in the general thread. That's a good idea. Thanks

For a quick answer... You can go to my website:

http://user.xmission.com/~dingebre/Synthasystem.html

My "official" forum, not much activity.

http://electro-music.com/forum/index.php?f=189

And a thread dedicated to the Steiner Microcon synth in a box I reassurected

http://www.electro-music.com/forum/topic-49530.html

Chris at Synthcube.com is selling some of the Modules as kits and assembled. I offer PCBs. Nyle gets half of any net profit from my sales.

Nyle started his business in the 70s selling modular stuff and he was my neighbor. The longer version is on my web site.

Very cool and unique stuff.
Isaiah
Great work, David! thumbs up

Another thread for those interested in the resurrected Synthasystem:
https://www.muffwiggler.com/forum/viewtopic.php?t=49580&highlight=synt hasystem
goom
Very nice, David!
davebr
Very nice indeed. If anyone is interested I took some photos and quick scope measurements of a Moog 984 that I recently restored. I made a web page for each of the modules since there is so little documentation and photos available.

Moog 984 Four Channel Mixer

Dave
dingebre
davebr wrote:
Very nice indeed. If anyone is interested I took some photos and quick scope measurements of a Moog 984 that I recently restored. I made a web page for each of the modules since there is so little documentation and photos available.

Moog 984 Four Channel Mixer

Dave


Thanks for the kind words Dave. And, a big public thank you for your help when I was struggling debugging the tone control section in my prototype. I will also highly recommend your site for the Moog info and a wealth of other useful and interesting stuff.

David
krisp14u
Thanks to David for the PCB I am now the very happy owner of a Moog 984 matrix mixer It's motherfucking bacon yo



I have been talking with David about the possibility of making a small run of mixers the same as the one I have built with a panel from Ben

Its maybe not for the space conscious 5U user but well worth the space if you have it

I’m loving the way the EQ and the whole thing colours the sound

I need 5 builds to make it worth it and the price would be around 270-290 GBP + shipping

this is not something I will be stocking but more a one off build for anyone who would like one but doesn't have the skills
Stereotactixxx
That is one sweet looking matrix mixer. While I'm not sure I can justify another mixer atm, I am intrigued and I have been lusting for an output mixer. I have a few questions though. What kind of signal levels does it expect? Will signals overdrive nicely over a certain level? Is the mixing part similar in design and sound to the CP3, except for being AC coupled? What kind of output levels can/will one get out of it, and will it play nicely also within a patch, not just as an output mixer?
dingebre
Stereotactixxx wrote:
That is one sweet looking matrix mixer. While I'm not sure I can justify another mixer atm, I am intrigued and I have been lusting for an output mixer. I have a few questions though. What kind of signal levels does it expect? Will signals overdrive nicely over a certain level? Is the mixing part similar in design and sound to the CP3, except for being AC coupled? What kind of output levels can/will one get out of it, and will it play nicely also within a patch, not just as an output mixer?


This mixer is a faithful reproduction of the original (but in a slightly narrower panel). As such, it expects the original Moog levels which I think were 2.5Vpp. That said, it works well in my system which runs about 10Vpp. It overdrives nicely and the tone controls add some nice highlights to the output.

The CP3 and 984 are completely different designs. The 984 is a 4 channel matrix mixer with a three transistor, non-inverting, AC coupled signal path with tone controls and a modest gain of about 1.25. The matrix also allows for recombination, too (see page below from the moogarchives.com site)

The CP3 is a DC coupled mixer with a gain of about 2.5 (I think) with inverting and non-inverting outputs.

Dave Brown was an huge help in this project and the photos and other information at his site were invaluable. He had the chance to repair/rebuild a fairly large Moog system and documented it extensively.

http://www.modularsynthesis.com/
http://www.modularsynthesis.com/moog/moog.htm
http://www.modularsynthesis.com/moog/984/984.htm

Otherwise, Dave's site is just a great resource.

I think the 984 was intended as a final output stage but since this goes in a modular synthesizer, you can put it anywhere in the signal path you want, right?
Stereotactixxx
Thanks for the extensive reply David.
The more I think about it, the harder it is to resist.
If Paul produces a small run of this, I'm getting one.
davebr
I did my own 2 channel final output mixer and feed it with the split from a fixed filter bank. While restoring the Moog, I will say I was quite impressed with the 984 and thought the tone controls actually added a lot. If I wasn't out of space I would probably redo my system and incorporate one. It is a nice design and a very nice redesign.

Dave
modularsynthesis.com
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