extreme Moog MG-1 Realistic Concertmate expansion/mod kits coming soon - and a request for opinions!

[belltones]

OK folks, bear with me because I have both a lot of information to deposit here, and a sort of convoluted request for opinions! gonna break it into 2 posts.

So I am closing in on imminently being able to release something I have been working on on and off for a couple years, what I have dubbed the "MG-1 ModEx" expansion/mod kit for the "Realistic Concertmate" Moog MG-1. To my knowledge, this might be the "most extreme" analog MG-1 mod design ever, um, presented, and I have particularly designed it for use with Eurorack and other modular gear, with 3.5mm jacks for all inputs and outputs, all inputs and outputs buffered and all inputs attenuated and capable of accepting positive and negative CV for maximum modular compatibility.

What I think are the two most important features that it offers are:

1) *Fully Independent* 1V/octave tracking pitch control for each of the two oscillators. I have done this by adding a second, fully independent tone source CV summer/scaler for Osc. 2. With an external sequencer or keyboard, this makes it a para-duophonic synth! You can play chords with one hand, send in a bassline from a sequencer and play a lead with the other hand. Oscillator 2 can also track the keyboard normally.
2) a second LFO with two waveforms, triangle and square, simultaneoulsy available at separate outputs. This LFO has a very wide frequency range.


I am awaiting polycarbonate panel overlays from Cubbison, design shown above (basically the same material as the original).

The PCBs are done:



Other features include:

• Modulation input for “Polyphony” (organ) section with depth control– add vibrato or something weirder

• Transpose control for oscillator 1

• Oscillator 1 individual high amplitude output to use as a modulation source

• Keyboard bypass switch for oscillator 2 – this allows you to, for example, either have the MG-1 keyboard transpose your incoming Sequence/arpeggiation, or have it be completely free-running while you use the keyboard for other things, or just set it as a pedal tone (drone)

• CV input depth control for oscillator 2 allows you to also just use incoming pitch CV for modulation if you want

• Pulse width modulation input with depth control for each oscillator. Pulse width modulation depth pots become direct pulse width control when no modulation source is plugged in.

• Additional filter CV input and depth control (modulate the filter with a fast LFO and a slow LFO at the same time!)

• Gate/V-trig input for envelope (V trig to S trig conversion).

• Envelope CV output (send it to PWM! Send it to Oscillator 2 and make a sync sweep!).

• Multi-trigger generator with on/off switch. Under normal circumstances, if you are holding a chord with the polyphony and trying to play a melody, for example, the MG-1 would only trigger its envelope on the first note. Multi-trigger allows it to retrigger with every key pressed– but you can also turn it off if it’s not helpful for what you’re playing.

• The option to also add a little separate PCB I make called "Universal Basic Input" to allow for output-input feedback and patching in of external signals into the pre-filter mixer. What this does is normal the output signal to a jack which is fed through an attenuator so it can be turned down to nothing or way up for crazy feedback; then, external signals can be plugged in and when using external inputs there is an optional level selector switch (line level vs "hot" for Euro level raw oscs etc). This is a little board with just a jack and single pot (and attenuator circuit) which is mounted into the rear panel and secured by just the control nuts.

A couple demos of the second prototype. A photo of the first one I did is in my user icon!:

https://www.instagram.com/p/Bs7EQ6bjcP1/
https://www.instagram.com/p/Bs8f66XDy3S/

I will definitely record more (and with better audio) when I make a nice looking one with the new overlays!

My guess is that the kit would be somewhere around $200-300 (that would be including all parts, so less if you just wanted to buy the PCB+overlay) but I haven't priced it all out yet.

Now here's the thing. The mods involve 18 op amps and add 7 pots, 12 jacks, 2 switches, and an LED to the panel, which requires connecting *54 NEW WIRES,* many of which have to be fed through the panel PCB by drilling small holes in it (I know this sounds nuts but there really is no other way, the panel PCB really does fit too snugly to add a lot of wires running across it and still be able to fit it into the panel). I set up the mod PCB to have all of the wiring run to a series of 0.1" pitch connectors on the upper edge of the board, but it is a still absolutely crazy installation. The whole time I have been working on this, for MONTHS, I have been thinking "Is this insane? Will I regret having unleashed this into the world? Will I be having to help people who mess up the installation for the rest of my life? Will I loathe installing them myself when I do commissioned builds?" I fear the answer to all of these questions is YES. I have been dreading making the build/install instructions for it for months.

I was chatting about it with Rob from Retroaktiv and he suggested something that was already scrabbling around in the back of my mind, and hearing someone else say it too made me think I should just do it: making an entirely new panel PCB that replaces the entire original "synth board" (panel PCB) and has all the mods built right in. (continued)

[belltones]

(continued)

So, now that I finally have the *final* PCB version finished and was just about to start making the install instructions, I've 90% decided to scrap that whole plan and remake the whole thing with a new, big, full-panel PCB. The advantages are obvious.

• No wiring for the person building/installing it AT ALL if I sell pre-crimped cable harnesses. All of what are hard-wired connections on the original MG-1 panel board can be replaced with pin connectors, with one end of the cables plugging into the new panel board and the other to where they go to the original lower PCB.

• If the synth section of your MG-1 doesn't work, you don't even have to fix it. Only the lower PCB and keyboard are retained and have to be working.

• New sliders and switches would be built right in. I've found manufacturers that make near-identical or identical parts for both, so they would retain the look and feel of the originals, and am awaiting price quotes. This will also mean if your MG-1's controls are gunky from the black goo you don't even have to worry about it.

• It will not be the serviceability nightmare it otherwise would be

• It will be fairly easy to "roll back" to the original PCB if you want, though there will be new holes drilled into the panel.

• It could easily be adapted into a standalone CV-controlled desktop synth module as well (though the polyphony features would be missing)

If I do this, I will also take the opportunity to upgrade the crappy digital noise generator chip to an analog noise generator circuit.

Obviously, this product-- bigger PCB, more parts, including sliders and switches... would cost more, at least $100 more per kit/unit.

So I'd like to ask:
1) how many people might be interested in this product (MG-1 ModEx kit) in either form? Would anyone be interested in doing a pre-order once I've gotten a bit further with the new PCBs and priced out the new version?
2) does anyone think they'd rather have the "raw PCB" version where you connect 54 wires by hand either to save $100-$150, because you're concerned about the characteristics of the original synth being lost due to using new parts or because it, say, "seems more fun?" Or should I not even worry about making install instructions for that?
3) any other thoughts or questions.

Thanks in advance!

[Jarno]

Nice work!
But, we don't exactly trip over those synths over here in europe, how is this in the US? Are these synths easily available?

[belltones]

@Jarno, actually one of the reasons I chose this synth as the "target" for this project is because they are quite ubiquitous and relatively cheap in the US. Definitely the absolute cheapest Moog-- you can still find nonworking ones for ~$300 on Ebay pretty often which is hundreds less than the VERY similar Moog Rogue. They were designed by Moog but mass-produced and sold by Radioshack in the 80s which was a mainstream consumer electronics retailer (answering machines, batteries, radios, electronics parts, etc), when Radioshack decided it might be fun to "do a synth."
It didn't occur to me, though it should have, that the MG-1s would be much rarer in Europe and therefore the appeal of this to Europeans would be much less clear!

[Synthwizard]

I want it. Im going to mail you my MG-1 now.
A whole new synth PCB might be a good route, but at that point just reissue the synth in desktop

[KSS]

than the VERY similar Moog Rogue. They were designed by Moog but mass-produced and sold by Radioshack

You've got that backwards. The MG-1 was designed by Paul Schreiber, working with moog engineer David Luce. But Paul did the work. paults is a member here and has shared the story a few times online at various forums.

Here's one of them. Towards the bottom I've bolded where the Rogue came in. Paul said in another reply at another time that the MG-1 wasn't a good seller for RS. An ad starring Elton John didn't make a difference and RS blew them out at a loss. Only about 500 were made if I'm rememberting correctly.

Date: Sun, 25 Apr 1999 14:46 -0400 (EDT)
From: Cary Roberts
To: Analogue Heaven
Subject: [AH] Paul Schreiber's "Moog"

Forwarded message:
________________________________________________________________
Date: Sat, 24 Apr 1999 23:20 -0400 (EDT)
From: Paul Schreiber
Subject: Re: Paul's "Moog"

>Paul S. designed the Radio Shack Moog! I'll be damned.
++++++++++++++++++++++++++++++++++++++++++++++++

Since this pops up every now and then, and I'm taking a break bagging up
7,620 resistors, here is the "story".

Radio Shack has no engineering. Rather, that falls (er...'fell') under TSD
(Tandy Systems Design). Also, twice a year Radio Shack holds a private version
of COMDEX/CES, just for them! Vendors line up 50 deep and present their wares.
Back then (early '80s) about 40% of gear in a Radio Shack was bought 'outside'.
Most electronics was made in a Korean factory that Tandy owned a majority
share called EnCal (EnCal made all of Pioneer's and Alpine's car stereos
there).

So, during one of these mini-trade shows who is on the presentation list
(which TSD got in advance) but a one 'Dr. D. Luce'. Well, when I saw Mr.
PolyMoog on the list I had to see this. So sure enough here he wanders in
with a hand-made small synth. He demos it. Bernie Appel, the #1 decision maker
(er...the *ONLY* decision maker of what went in the store or not) had this type
of conversation (I am giving not exact, but the general idea. It was 16-17
years ago!)

BA: What the f*** is that piece of s***? (BA enjoyed treating all new
vendors this way. This was his equivalent of "Hello.")
DDL: It's a music synthesizer prototype. [Proceeds on a 3 minute demo. You
had 5 minutes to present. Period!!]
BA: (interested, but certainly not going to show it to the Yankee geek) How
the hell do you plug it in?
DDL points out the 1/4" jack.
BA: Where in the holy hell, in my store (they were always referred to as "my
stores") does that thing go? Up my ass?

See, RS had not a single piece of gear that had 1/4" jacks! All RCA. BA knew
this.

DDL at this point looks like he's gonna puke. He's quivering & sweating like
a whore in church (sorry, that's another BA expression!)

BA: Play me a tune. [DDL one-fingers a classical thingy.]

BA: That damn thing busted? What's with this 1 finger shit?
[DDL explains about monophonic blah blah blah.]

BA turns to me.

BA: You know what the hell he's talking about?
Me: (thinking this is a trick question) Err...yeah.
BA to DDL: We'll look at it. NEXT!!!!

So began the Luce/Schreiber effort. What he had was the boards out of a
Minimoog, no A440 osc, no noise, in a box. So, I got handed that, designed
the MG-1 version (added the organ stuff BECAUSE BA was convinced that typical
RS customers wanted more than 1 note). Added RCA jacks, ring mod do-dad. Then,
had to specify parts that Moog never had to use: cheapo pots. I'll admit it:
CHEAPO. They were ALPS and I think we paid (back then) about 23 cents apiece.

That is because the RS gross profit margin was an unheard of 63% (the
average of ALL the Forture 500 is like 8%) and lastly, I spent about 3 weeks
on just the panel layout and color scheme & wrote the Owner's Manual along
with, oddly enough, Steve Leininger who designed the TRS-80. He played a Vox
in a jazz band and BA wanted his opinion as well.

Luce and I went back & forth about 5 months until they delivered the
"pre-production" units. Moog made them, Tandy supplied most of the parts (we
had a company in Japan that bought parts and resold them to Tandy. One day
I'll tell my funny modem capacitor story.)

So, the story was:

a) Moog presented the original idea to RS
b) They dumped it on me. I had to make it "Radio Shack compliant". Which
meant a re-design. Used the 3046 + Tel Labs tempco for the VCO. More
Electronotes than Moog! Moog ladder filter, 3080 VCA. Prototype had mod
wheel; *PUNT!*. Cost like $3. Get real.
c) Moog built it.
d) Tandy had 18 months exclusive. Moog then made the Rogue which is my
design without the organ/ring mod, wheels back on.
e) No, I didn't get a free MG-1 or a Rogue.
f) No, I didn't get alot of money. At that time I was making about $21,500/yr.

Final note: NO!!! I DID NOT pick that stupid black felt that lays over the
sliders, then turns to tar. That was Luce's deal. But, I DID get Luce to send
me *every* piece of Moog literature at the time: still have it!

Paul Schreiber
Synthesis Technology

[analoglsd]

I'd buy a couple...

[belltones]

OK @KSS... I guess I was mistaken about the backstory! I thought I'd read about it when I first got my first one about 10 years ago but maybe I didn't, or maybe what I read was just speculation. I should get my facts straight so I know whose work I'm undermining! But my other initial thought was that there's no way that

Only about 500 were made if I'm rememberting correctly.

just because of how ubiquitous they are, at least in the US. I have one I've had for many years and have bought two more for about $250-300 each over the course of doing this project, I have two currently in to do this mod for, for clients, and at my shop we've worked on at least 10 more. It's hard to imagine that the ones that have passed through my hands could be 3% of all the units in existence, but I did get concerned that it was somehow true (which would seriously dim the prospects of this project) and looked at the serial numbers of the ones we have here now, and they are 4430, 4997, 8699, 14100, and 15581... unless they had some kind of really complex and convoluted method of using 5 digits to represent 3 digits of data or very weird way of doing date codes I'd think that there were at least 16,000 or more likely 20,000 made. Even if they started at 4,000 the ones I have represent a pretty good distribution of values between 4,000 and 16,000. I'm relieved!

[belltones]

I'd buy a couple...

Cool, any thoughts on what format you might prefer (full panel or separate mod board)?

[analoglsd]

I'd buy a couple...

Cool, any thoughts on what format you might prefer (full panel or separate mod board)?

Full panel

[cooties]

I didn’t think it could be possible to squeeze more fun out of the MG-1 than it already provides, yet here we are I’ll commit to take two straight away, and will probably grab more afterwards, in ones and twosies. I see MG-1s here all the time and I know this would be a popular mod. As you know, whenever one’s on my bench, I’ll always buy your dust shield kit, too!

My personal choice: the cheaper mod board with the through-wires. I’m biased, as I can handle the complexity of implementing all that wiring/soldering, but I know that’s not going to be everyone’s cup of tea. Oh, and if you end up just offering full panel, I’ll take them too.

[Lackan110f]

Nice project! I myself made some very useful mods to mine a while back, and to me you seem to got the most important enhancements in place, but some are missing

In my opinion I think you should also look at:

• Sustain, for a ADS- or ADR envelope. Makes a ton of difference. More than you would think actually.
• Transpose -1 oct for both OSC's since they by default are rather high pitched.
• Overdrive for a more saturated output

Have you seen the MG1 mod thread on the moog forum by a guy named "Facon"?
https://forum.moogmusic.com/viewtopic.php?f=1&t=22856

Some really useful tips there.

I choose to call mine "Moog" since that is what it is. The Moog name already is on the PCB.
(Although I understand this is difficult since you are doing this commercially. No need for anyone to start a copyright lesson here.)

As I said, great project. Best of luck!

[belltones]

Thanks folks!

In my opinion I think you should also look at:

• Sustain, for a ADS- or ADR envelope. Makes a ton of difference. More than you would think actually.
• Transpose -1 oct for both OSC's since they by default are rather high pitched.
• Overdrive for a more saturated output

Oh, one thing I forgot to mention while running through the features is that I also expand and trim the Osc 2 transpose range to be able to drop Osc 2 by a full octave. I'm halfway with you there.

The sustain was definitely one thing I went back and forth on whether to add, considering doing a Minimoog style envelope where in this case, the release time control is appropriated as decay as well (compared to vice versa in the Mini, but functionally the same) but in the end it didn't make the cut. I decided it wasn't worth it to have to add the amount of extra wire connections to the mods PCB that it would take to have the new components there, looped into the original AR circuit and to the sustain level pot (the design I was going to use would have added 5 wires). If I'm doing it as a separate PCB that is added and wired in as was my original plan, I've completely maxed out what can fit on the mods PCB. The mods PCB has to fit in a very specific space between the transformer, other (lower) PCB and keyboard. It can't be more than 2-3 mm larger in either dimension than what I've laid out in my very tight layout.
But if I do a fully new panel PCB I will be able to reconsider the option of putting sustain in. If I decided to, I would probably take the opportunity to redesign the envelope entirely to make it a Minimoog style ADSD (in this case ARSR)! I'd just run into the challenge of where to put the control pot for sustain level, because in my current panel overlay layout I have nowhere to put one.

Doing a whole new panel PCB increases the danger of "feature creep" because it makes me tempted to just change every little thing about the synth I don't like! At a certain point, is it even the same synth at all? Where should I draw the line?

Legal concerns: I know for a fact that it would be a legally terrible idea to slap the currently in-use, registered-trademark Moog logo on it, so that's out of the question. I'm even very wary of altering their design a lot, making a new overlay and putting the word "Moog" on it at all (though it was my plan). That might already almost qualify, or even actually qualify as "producing counterfeit goods." I think if I'm making a new PCB it will bring things even closer to that point. But I can't just not say "Moog" on the new overlay as if I'm pretending that I invented the whole thing! I'm hoping the scale of this venture is small enough that Moog won't care, but I can't be sure. I might ask a friend who is a lawyer about it, but I feel like he'll probably tell me I'm pushing my luck. I guess I could ask Moog but I'm scared they'll just forbid me from doing it, even though the scope of this venture is so small ("maybe I can make a couple grand if I'm lucky!") that I feel like/hope they shouldn't care.

Finally @Lackan110f, regarding overdrive, I'm not sure how you implemented it, but I think if you add the "supplementary" Input/output feedback board I mentioned it does it one step better!

Oh, here's a picture of that PCB by the way:

[KSS]

[DJMaytag]

Only about 500 were made if I'm rememberting correctly.

I'm pretty sure this isn't correct. My understanding based on serial ranges (not the actual serial numbers themselves) was that several thousand were made. Moog & Tandy/RS aren't exactly companies that do small production runs.

[KSS]

I'll have to ask paults. I probably slipped a zero, but will be surprised if it's more than 5K. There was quite a writeup-dustup about it a few years ago. Others were then -as now- surprised too.

[CollinRussell]

Were these PCBs ever released? Didn't see them on the belltones site.