Rivera Music Services Engineering Brief and Photo Sheet for Minimoog Modifications, 1980

Rivera Music Services 12-page Engineering Brief and Photo Sheet for Minimoog Modifications from January 3, 1980.

Engineering brief also available as a PDF (4MB).

It's a lot of text, sure, but if you are a Minimoog modding freak or just a modding addict in general it's well worth the read!

These scans all began (that rhymed!) when someone in the Moog Fan Club Facebook group asked if anyone had a close-up photo of the Rivera Music Services (RMS) Chromatic Transpose Minimoog mod. I knew I had a glossy photo sheet of a fully modded RMS Minimoog somewhere that I could get a sweet close-up scan from, so I went digging and in the same sleeve was this engineering brief as well.

And what do you know... it comes with a price sheet. That's some historical gold, right there. And a good reason to scan everything and post. :)

A lot of the content of the engineering brief actually appears in the "RMS Modified Minimoog" brochure that I posted about a year and a half ago. But there's a lot that's different too, including prices!

So, it made sense to do a small comparison between the two docs... and I guess readers of the blog are coming along for the ride.

For a start, the engineering brief contains a whole new first section of mods called "Updates" that RMS said would increase the stability and reliability of a stock Minimoog. This included options for:

• New stabilized oscillator board - $320
• Octave range buffers - $70
• Power supply updates I - $80 and II  - $40
• service check $55

*None* of those are listed in the brochure! Excellent stuff.

The next section in the brief is called "Custom Features", with an array of options that "provide new and unique sounds, functions, and control capabilities". This includes a number of features also found in the brochure I posted earlier. I've included prices for each feature with brochure prices in brackets for comparison:

• Fine tune control:
  Osc 2 - $40  (brochure: $55)
  Osc 3 - $40  (brochure: $55)
  Master tune  - $40  (not in brochure)
• Beat tune  - $105 ($89)
• Ribbon controller with pitch wheel reassignment  - $190 (not in brochure)
• Chromatic transpose with assignment switches  - $185  (brochure: $189)
• Preamp mode - $35 (brochure:  $29.50)
• Distortion - $50 (brochure: $49.50)
• Sync (Osc 2 and 3) - $170 (brochure $174.95)
• Contour (Osc 2 and 3) - $100 (brochure $79.50)
• LFO 4 - $150 / $180 with LED (brochure $149 includes LED)
• Modulation pedal  - $90 (not in brochure)
• Keyboard trigger  - $125 (brochure $129)

The final section in the brief is called the "Interface Capabilities" which added features to allow your Mini to "patches involving other synthesizers, controllers, processors and studio equipment. Again, most of these were available at the time the brochure came out as well:

• External CV assignment - $90 (brochure $129.50)
• Oscillators, filter, and keyboard CV and date outputs - $200 (brochure $124.50)
• V-trig to S-trig conversion cable - $40 (brochure has built this into the Mini as a V-trig input jack  - $49.50)
• Separation of keyboard and console - $250 (not in brochure)

I originally estimated the date of the brochure at 1981, and I was hoping I could compare prices to this engineering brief dated January 1980 to get a better date estimate. I figured if prices in the brochure were higher, then an '81 date would still make sense. If prices were lower, then I'd probably date the brochure a bit earlier... maybe 1979 or even 1978 

But they aren't uniformly more or less when compared! For example, the Fine Tune Control mod costs less in the brief than in the brochure, but Beat Tune mod costs more in the brief than in the brochure. Gah! 

It's also interesting to note a few features from the brief don't appear at all in that brochure - the whole service section, but also the modulation pedal, keyboard separation, and the ribbon controller. The pedal and ribbon controller are just external hardware I believe, no real "modding required", so I can see those being left out just to give more space to actual mods. 

And the separation of the keyboard from the synth is not really a mod - its more a massacre of sorts and probably couldn't really be done by your friendly neighbourhood tech. So that, and all those service mods could probably be excluded from the brochure without too much worry too. 

But still... I like consistency. Maybe some future RMS docs will help me out. 

Rivera Music Services (RMS) "The RMS Modified Minimoog" brochure, 1981

Rivera Music Services "The RMS Modified Minimoog" brochure from approximately 1981.

It takes a fair bit of equal parts motivation and curiosity to get me to sit down and write a blog post lately, and I gotta say the perfect storm happened recently. Motivation came in the form of alcohol, while curiosity came from last year's reissue of the iconic Minimoog and the recent urge to get my own '80s Minimoog modified.

And so, meet one of the original mod'sters of the synth world - Rivera Music Services out of Boston. They modded a few different synths in the late 70s and early 80s, and some of their most well known surgical procedures were done on the one and only Minimoog.

This brochure provides a great "wish-list" for anyone wanting to get their Minimoog modified, and theoretically, if the innards of the old and new Minis are close enough, any mods listed here should be able to get done on your brand new re-issue'd Minimoog as well. But - I have no data to back up this claim - just musing is all.

But evidence of this claim comes from the new Minimoog itself. It appears at least one similar modification was already included in the new reissue - the addition of a dedicated LFO (called LFO 4 in this RMS brochure). Nice!

Before I go any further into specifics on the RMS mods, I just gotta say something about the brochure itself. And in particular, about the folding used.

The 10 page brochure uses a double gate fold, but because of the extra page (five "pages" a side), one side of the gate has to have an extra fold to make it work. That way, when the brochure is fully closed for mailing, the photo of the modded Minimoog appears on the front (page 4) and the address label appears on the back (page 3).

Then, when someone received the brochure in the mail and opened it,  page 5 ("Introduction" page) and page 2 ("In summary/A special note") would have been the first "inside" pages they saw. Flipping it out the rest of the way (one flip on the left and two flips on the right) then reveals all the details of the mods that are written on side two of the brochure.

Mind blown!

It's an interesting fold and a designer would definitely have had to have known their folding options to make it work properly. Kudos!

Okay, enough about the folding. Let's get to the meat of this brochure. As stated earlier, the brochure provides a great overview of the main mods available for the Minimoog.

RMS divided their mods into four categories - with a page devoted to each. All mods are available individually as well, as priced out on the last page of the side two.

Curiously, the first category is best described as other mods - or as RMS refers to them "In a class by themselves...". These mods include:

• Fine Tune control  - with no backlash (ie: there is no tuning drift when your hand lets go of the knob)
• LFO 4
• Keyboard Multiple/Single Trigger Select (allowing the CG to fire whether or not the previous key is lifted)

The second category are referred to as "Tuning" mods that all directly affect the turning of the oscillators in unison or separately.

• Chromatic Transposition
• Beat tune (visually tune your Minimoog while the band is playing)
• Dead band on pitch wheel - increasing the "dead" zone in the middle of pitch wheel. 

The third set are referred to as "New Sounds" mods, that are designed to "increase the timbre range of the Mini by providing new modulation and control capabilities.

• Sync for Osc 2 and 3
• Contour control for Osc 2 and 3 - apparently super cool for drum sounds
• Pre-amp mod - produces a unique type of distortion similar to a ring modulation
• Distortion - a "cleaner and smoother" distortion than the pre-amp mod

Finally, the forth set of mods fall under the "Interface" category, providing even more unique functionality.

• External control voltage assignment (control each Osc individually!)
• Individual outputs for Oscillator 1, 2 & 3, and filter (Wowza!)
• Keyboard control voltage and gate outputs
• V-trig input jack - so your Roland sequencer can now control your Minimoog WITHOUT an s-trig converter - sweet!

That is some dang good history hiding out in those pages! Definitely take the time to read through the brochure for more info on the mods. And keep reading, because the best was yet to come - the price list!

Bingo! 

When reading the prices, remember that these mods are in 1980s dollars. The "full package" was originally priced at $1,087.95 - or about $3,150 in today's dollars.

Costly. Maybe. Worth it. Definitely.

And I have other docs that show these weren't the only Minimoog mods RMS provided.  So lots more to come from RMS shortly. And by shortly, I'm hoping in less that four months...  :)

So, who has the guts to attempt these mods to their new Minimoog? Or have you already? Let me know!