ARP Omni symphonic electronic keyboard advertisement #2 from page 29 in Contemporary Keyboard February 1977.
If you read my first Omni ad blog post, you may have noticed I didn't touch on one certain aspect of that ad - the demo sound sheet that was obviously attached to the centerfold between the two pages of the ad. Now I have no choice but to touch on it since ARP was smart enough to keep the demo record promo thing going for the next two months with this single-page advertisement - an ad that showcases a shiny close-up image of the sound sheet. Again - smart move ARP, one month of promotion just wouldn't have cut it. More on that promo record in a second.
In that first two-pager post, I really focused on one question - the manufacturing start date of the Omni. Most online resources, as well as Mark Vail's "Vintage Synthesizers" book have the manufacturing start date of the Omni beginning in 1975. But, based on a lot of evidence, including commentor Micke from my last blog post, I questioned when the Omni really started to be commercially available - and hinted at a much later date. Say, late 1976.
This ad piles on even more evidence to this theory. For one, the first sentence in the ad copy is:
"The ARP Omni is an incredible new electronic keyboard you have to hear to believe"."new". That's pretty clear-cut. But there's more.
If you look at the small address form that readers could fill out, you will learn that for $1 you can send away "to receive your demonstration record and complete information on the ARP synthesizer line."
And if you look even more closely at the photo in that form, you will see that at the top of the pile of ARP information (*drool*) is the October 1976 issue of ARPeggio - ARP's newletter. You can barely make it out, but that issue has Less McCann on the front cover with the title "Less McCann 1st to Try New OMNI". And, if you had a copy of the newsletter, you could flip to page 7 and read the article titled "New ARP Omni: Completely Polyphonic". Content of both articles make references to the "new" ARP Omni. And this is the October 1976 issue! Granted - ARP newsletters weren't too frequent, but still... the evidence for a later manufacturing start date just keeps mounting.
You can view the full newsletter online - I scanned all the pages and blogged about it back in June.
Okay, now that I got that out of my system...
My second-hand copy Contemporary Keyboard didn't include the attached demo sound sheet, but over the years I've manage to pick up a few copies of what I believe is the same one. The Omni demo I have is performed by Tom Piggott, who worked at ARP and was one of the three ARP authors of the book "Learning Music with Synthesizers". It includes examples of all the sounds - violins, violas, string cello, bass, and synthesizer section, many of them played in combination. There is also a comparison of the instruments with the wave form enhancement, chorus/phaser, and stereo effects enabled so the listener can get a really good understanding of just what $2300 or so bucks gets ya. Split and footswitch capabilities are also showcased.
I found a copy of the mp3 online at peterunderdog.com's ARP Omni resource page. The "Sounds" section includes the link to this mp3, as well as a link to another Omni demo recording that unfortunately is broken (the link - not the record :o) That Omni site also includes some good tech and repair information, along with links to other ARP-related sites.
In my last blog post I linked to two other Web pages that included some other good Omni reference info - but here they are again - Wikipedia and Vintage Synth Explorer. Definitely check those two out if you want to learn more.
As I was surfing around looking for more good reference material, I also started to look at more and more photos of Omni's through Google's Image search, and my curiosity turned quickly to the "Waveform Enhancement" switch. Never heard of it before.
According to an ARP Omni page on cy-gb.facebook.com, the switch "allowed selection of a square wave voice waveform vs. the default quasi-sawtooth waveform". An ARP Omni service manual (PDF) I found on Synthfool describes the feature as "altering waveforms produced by the Omni to a hollow like (square) sound".
There is a bit more detail on how the basic sound of the Omni is obtained, and how the Waveform Enhancement sound is eventually created, in section two of that service manual (theory of operation, page 5):
"The OMNI's tone generator circuitry consists of a master oscillator at 500 kHz., which drives a large scale integrated circuit top octave divider. The top octave divider produces the highest twelve tones in the instrument. Frequency dividers derive the remaining pitches from the top octave divider. The squarewave outputs of each divider are waveshaped to a sawtooth form (the waveform enhancement alters the waveshape to a differentiated squarewave)."A few sources on the Web indicated that you can hear the Waveform Enhancement sound from the Omni in the lead line from Modern English's I Melt With You. I've included the YouTube video in this post so you can hear the sound yourself, see the Omni in action at around 1:52, and most importantly, to get "extra points" from my girlfriend, who loves this song. :o)