Moog 902 Voltage Controlled Amplifier brochure, 1976

Moog 902 Voltage Controlled Amplifier four-page brochure from 1976.

Voltage Controlled Oscillators aka V. C. A.  aka Y. U. M. :)

If you are keeping track - this is the forth brochure in the series I've posted. You can view the other posts by clicking on their images below.

Like all the brochures in this series, the front cover includes a nice close-up shot of the module itself.  The 902 VCA brochure resembles the VCO brochures in that it includes four pages of deliciousness. Flip open that gorgeous cover and you are greeted with the brochure copy on the left and some official looking diagrams on the right. And ultimately, specs on the back page.

One thing I haven't been freaking out about lately is that Moog logo. I love logos. Especially the old-skool logos like Moog, ARP, Sequential and the like. In all of these brochures, that lovely Moog logo is right there at the top.  And the best part is, that Moog logo design is the one still used today. Nice.

But, did you notice that the location of the Moog logo on these brochures isn't constant. It's always on the opposite side that the module photo is on. Module on the left - logo on the right. Module on the right - logo on the left. Interestingly, the one brochure where the logo is on the right is also the only brochure I've posted so far that was printed in 1974 - not 1976 like the rest of them. Not sure where I'm going with that - just an observation. As I post more, we'll see if the pattern sticks.

I've never paid too much attention to VCAs until I really got into modulars. On most "regular" (read: non-modular) synths they usually just kinda sat there, almost invisible, next to an envelope generator or whatnot. They really do get the short end of the stick on most synths.

Comparatively, VCOs have wave form selection buttons, octave knobs and various other doo-dads. VCFs have, at their most basic, cut-off and resonance controls. More advanced VCFs even let you choose the type of filter -low pass, high pass, bandpass...  lucky ducks.

But VCAs... Maybe a volume knob. Waaaah.... waaaaaah.... On an Korg MS20 it's just an image of a triangle. No, really. The Yamaha CS15 has one control to adjust initial volume (besides the modulation controls for LFO and EG).

I guess my point is that its not surprising how little we pay attention to them.

I was lucky that my Moog Modular came with three VCAs, each sitting next to an envelope generator. So, it dawned on me early on how important their role was. More importantly, it dawned on me *before* I started creating my Eurorack modular. It's quite common out there to get a Eurorack system started without figuring VCAs into the equation. 

Aside: speaking of Eurorack, one of my favorite VCA-type modules at the moment is local (to me!) Eurorack module designer Hexinverter.net's Galilean Moons. And yes, I've paired it with his Jupiter Storm module too. Together they are almost too much fun in a box to be legal. He includes some great sound examples on those pages. Check 'em out.

But back to the point. VCAs *are* important, especially as your system grows and you start creating more complex patches. Don't believe me... Just read through this "Do I really need a VCA" thread on Muff Wiggler.

Some great quotes:

• Filch: "The general motto around here is : "You can never have enough VCA's""
• fredguy "I started out not using vca's much and then came to understand what they brought to the party."
• robkramble: "I totally derped and overlooked the use of a VCA as a CV router... "
• Matos: "No, you don't need a VCA. You need many VCAs!  "
• boramx: "i personally think you should have about 2 VCAs per 3u of modules."

And, I'll end this post with one other quote from forum member monobass:

"vcas are the next level shit y'all"

Yup.

Moog 903a Random Signal Generator brochure, 1976

Moog 903a Random Signal Generator two-sided brochure from 1976.

For the last couple of weeks I've been swooned by a series of Moog module brochures. This 903 Random Signal Generator brochure is the third in the series - after blogging on the Moog 921a/b oscillator bank and the Moog 921 voltage controlled oscillator module.

I gotta say, this series is shaping up to become a handsome set of brochures with those lovely front covers. Sweet.

There is one little difference with this latest brochure though. Those first two brochures each included four pages of juicy Moog-y goodness, but this latest 903a random generator module brochure consists of only one two-sided piece of paper. It's not a surprise though - that 903 panel is sparse-city, consisting of just dual white noise and pink noise outputs.  No big dials, switches or flashing lights in the local vicinity.

That may give someone not familiar with noise generators the wrong idea. A noise module is a MUST for any modular. The back of the brochure goes into some good detail on how noise can be used effectively within a patch. Percussive sounds - check! Sound effects - yup!  And of course there's the signal control applications as well like their involvement in creating randomly timed and tuned beep, boop, boop, beep, boops.

Growing up I loved noise. Not the really loud variety of clanging and banging (that came later) but that soothing noise that I find described so well by William Gibson in the opening line of Neuromancer:

"The sky above the port was the color of television, tuned to a dead channel."

I love that quote. and I also love the sound that often accompanied that screen "color" late at night when a television channel went off the air. SSHSHSHSHSHSHSHSH...

It wasn't until I got my Moog modular that I realized there was different "colours" of noise. And even then I wasn't too curious what the differences were for a long time. If you Google the topic you will soon learn there are a wack of different "colours "of noise - and as math is introduced into the equation (pun intended) if you are like me your head will begin to hurt a little bit.

According to Wikipedia, noise tends to be divided into two groups.

The first group are those colours of noise that have precise definitions:

White. Pink. Brown(ian). Blue. Violet. Grey.

In the case of this module, White noise has a "flat" frequency spectrum - "the signal has equal power in any band of a given bandwidth... when the bandwidth is measured in Hz". The example they use is that the sound power between the frequency range of 40Hz and 60Hz is equal to the sound power between 400Hz and 420Hz. Here's the chart for white noise from the Wikipedia page.

Pink noise, on the other hand, is linear in logarithmic space - "it has equal power in bands that are proportionally wide". Using the same example above, there is the same amount of sound power between 40Hz and 60Hz as there is between 4000-6000Hz. Now compare its spectrum chart below to the one for White noise above.

The visuals definitely help. :)

The second group are those with less precise definitions, synonyms for formally defined colours, or have multiple definitions - Red. Green. Black. Noisey White. Noisey Black.

I'm not even going to pretend I know *exactly*what they are talking about, but I get the idea.

I'll let you read the Wikipedia page to find out more info.

My head hurts.   :D

Moog 921 Voltage Controlled Oscillator brochure, 1974

Moog 921 Voltage Controlled Oscillator four page brochure from 1974.

Last week I posted the brochure for the 921a/b VCO bank from the same series. This 921 VCO is like the Simon to the Garfunkel of the 921a/b bank. The Captain to the Tennille.

Actually, maybe I should be using synthpop references. The Annie Lennox to the Dave Stewart of Eurythmics. The Vince Clarke to the Alison Moyet of Yazoo. The Neil Tennant to the Chris Lowe of Pet Shop Boys. The Marc Almond to the Dave Ball of Soft Cell. The Rob Fisher to the Peter Byrne of Naked Eyes. The Neil Authur to the Stephen Luschombe of Blancmange.

Okay, think I milked that one. Point is, chances are you will find both 921s and 921a/b banks making beautiful music together in a Moog Modular.

I mentioned in my last post how researched seemed to indicate that the 921 series came to be in part because the Moog Modular was transitioning from an experimental machine found mostly in music "labs" to that of a musical instrument to be found in some of the top professional recording studios. In particular, the 901 series was replaced by the 921 series with their better temperature stability, tracking accuracy and extra functionality - requirements when trying to churn out the next top 40 hit.

But these modulars were highly technical machines. And they required some technical knowledge to get up and running (and keep going).  Thus, this brochure is NOT marketing Moog modules to the average musician. And I'm not even sure if its directed towards the average studio tech either, although I wasn't hanging around in studios back in 1974 so can't really comment to their technical knowledge. The highly technical content leads me to believe this series of brochures was still being targeted towards the music lab gurus - and probably only the ones with the whitest lab coats, biggest pocket protectors and (in reference to the men) the biggest beards.

Aside: before you knock me for my nerd-bashing, I will have you know that I wear a pocket protector every day at work, and usually a different every day. Geeez - how else do people protect their pockets these days?!?! So, if you have any vintage (or new!) pocket protectors, please contact me! I'm serious.

Back to the point... were was I... oh yeah... targeted audiences.

To make my point, let's compare this brochure to the marketing material of another one of Moog's legendary products - the Minimoog.

Minimoog

No text whatsoever. :)

Yeah, I know - silly comparison. By 1979, the Minimoog was such a standard tool in the studio that not only did it not need more than 10 words of marketing content, but Moog didn't even have to slap a logo in their ad. So, okay, a totally shitty comparison.

A better comparison might be Minimoog's 1972 brochure. Here's the inside scan that links to the blog post.

So, this Minimoog brochure was printed TWO YEARS before the 1974 921 VCO brochure.

Let's compare the first real line of content of the two brochures:

921 VCO
"The 921 Voltage Controlled Oscillator generates periodic waveforms within a total frequency range from .01 to 40,000 cycles per second."

Minimoog
"Brutal, caustic, volcanic - Evocative, flirting, caressing - crisp, powerful, biting - Entrancing, embracing, exhilarating!"

Yup. Definitely different audiences. :)

That 921 VCO brochure content is definitely targeted towards those pocket-protected white-lab-coat-wearing music technicians while the text in that Minimoog brochure was obviously meant for the  tight-shiny-gold-pants crowd.

To be fair, there was some cross over between these two groups. And I have to say, those men and women in the lab coats *and* tight gold pants were definitely the most awesome.

I'm not saying Moog didn't create modular marketing material for a musician audience, I'm just saying this series of brochures was definitely not. 

Moog 921A Oscillator Driver/921B Voltage Controlled Oscillator brochure, 1976

Moog 921A Oscillator Driver/921B Voltage Controlled Oscillator four page brochure from 1976.

I knew it had been a while since I last published a blog post, but I didn't realize it has been about a month! Honestly, I have a wack of ads and brochures scanned, but just haven't been able to find the time to find the words. Summer and its ups and downs have gotten in the way a little bit.

But fall is now here! And although its been a pretty rainy one to date, this morning I'm happy to report I'm blogging from my sunny back deck, coffee in hand.

Perfect blogging weather. :)

I've been wanting to start posting this series of Moog module brochures for a while and the 921a/b was an excellent one to start with because there is some great history behind it.

As you may know from previous posts, I'm a big fan of Moog. I'm also an owner of a Modular Moog (see right). Although my modular contains the 901a/b VCO bank - the predecessor to the 921a/b bank - it provides a great back-story to existence of both.

Let's back up a bit. As you can see in my modular's patch diagram (created by Bob Moog himself!), there is both a 901 Voltage Controlled Oscillator as well as the 901 a/b bank that contains one 901a driver that is wired up to control (drive) three 901b VCOs. What's the point of having the 901a/b bank if you could just have 901s?

For a long time I thought the only reasons the 901a/b bank existed was because it was a great way to cram more VCOs into a smaller space. The 901 takes up a lot of room, so getting three or four 901b VCOs with multiple waveforms into the same space really was one convenience of its design. But then I found an even more valuable reason for the a/b driver system a while back when doing some research on my modules.

A PDF article titled "The 901a/b story"  found on synth-werk.com (a company that is building Moog modules!) explains that as the Moog Modular transitioned from a piece of experimental equipment to more of a musical instrument to be found sitting in professional studios and on stage, the 901's thermal instability and older electronic components resulted in problems with tuning. This was fixed to some degree by driving multiple 901b modules from one 901a controller. But, they were still pretty unstable, so Moog eventually replaced the 901 series with the 921 series giving musicians a lot more temperature stability, tracking accuracy and extra functionality.

Great stuff. And so is synth-werks as far I can tell. Definitely going to look into filling that top space in my modular. :)

The brochure/spec sheet is almost as much of a work of art as the 921a/b modules themselves. First and foremost, we get a great close-up of both modules on the front page. Then when you open the brochure up you are greeted with a wealth of knowledge - in fact, pretty much everything you've ever wanted to know about the control panel features and musical applications of the 921a/b. There is even a full page of technical charts and graphs. I'm not even going to pretend I know half of what Moog is talking about there. I'll take their word for it. Finally on the back page we get all the information specs.

I'm a fan of this whole series of module brochures, and you can expect to see more of them soon. But right now its just too nice out. Time to make the most of this gorgeous Sunday.