ARP Model 1601 Sequencer "Extra hand" advertisement - Part 2, Contemporary Keyboard 1976

ARP Model 1601 Sequencer 1-page advertisement in Contemporary Keyboard November/December 1976.

Part 2

If you don't want to read Part 1 of the blog post, I'll catch you up.

First I yammered on about the ad itself - design, ad-copy and it's general all-around creepy goodness. I also mentioned the Spec Sheet write up and other appearances made by the ARP 1601 Sequencer in other ads and promotional material.

Then I mentioned how I came across one recently, but got all grumpy trying to find consolidated information on the Web about it. Instead, strewn about the Web are a number of references to different designs and model numbers. And to make matters worse, ARP gave this sequencer a generic name - "Sequencer". Why wouldn't ARP give it a cool name like they did for the "Axxe" or "Odyssey"?

So, yah, I was a little grumpy last weekend. I'm much better now, thank you very much.

But later on, rather than keep being all angry about it, I decided to do something. Probe. Google. Catalogue. Organize.

First, although it looks like the Sequencer had two major "designs", I found that most people usually just refer to their unit as "ARP Sequencer Model 16xx". This number is usually found on the back of the machine with the serial number. But I did find one or two instances where others classify the Sequencer designs as Mk 1's and Mk 2's - probably because the ARP Odyssey uses a similar naming convention. Makes sense.

The differentiation between the two designs is easy to see - and the colour schemes basically match the last two versions of the Odyssey - which also helps in trying to narrow down manufacturing dates.

So, based on this naming convention (Mk 1 and MK 2) and the model numbers I was able to find online, I've summarized my findings below. It may not be everything, but it's a start:

Sequencer Mk 1 - model's 1601, 1611, 1612, and 1613
The Mk 1 is generally believed to have been initially released in 1976 with a black and gold colour scheme, matching the ARP Mk 2 Odyssey of the time period. Wooden side panels are also distinctive to the MK 1's. The appearance of the ads and Spec Sheet write up in 1976, and a 1601 Sequencer manual found on retrosynth.com that includes a copyright date of September 1976, support a 1976 release date.

For comparison purposes, I've included an image of a Mk 1 Sequencer from a 2008 e-Bay auction found on MATRIXSYNTH, alongside a photo of an ARP Odyssey Mk II image from Wikipedia.

So, where do you go when you want to get a good sampling of ARP Sequencers? Why, MATRIXSYNTH of course! And the site didn't disappoint - it had a number of ARP Sequencer posts with photos of Mk1s that also included model #s. Based on these posts, and other pages on the Web, I'm thinking that the Mk 1's included model #'s 1601, 1611, 1612, and 1613. Although, I was never able to find an actual photo of the back of an ARP Sequencer with a 1601 model number printed on it. I've only ever seen the 1601 referred to in the sequencer manual I found on retrosynth.com. Could it be that "1601" was the overarching model, and the 11, 12, 13 were the models within it? If you have a 1601 with the model number on the back, please let me know!

Here's a few example Web pages that included references to model #s.

• model 1601 manual found on retrosynth.com, in particular this cover image
• model 1611 from July 2010 auction.
• model 1611 anniversary edition with "old school coloured LEDs"
• model 1612 - serial #0001
• model 1613 with great high-res images
• model 1613 with a date of 1975?!?! I followed the auction link to e-Bay and it does say 1975. Huh.

Sequencer Mk 2 - model's 1621, 1623
I can't find a definite release date of the Mk 2 Sequencer, with its new black and orange colouring. And not only did the colouring change, but the Sequencer was also sporting a new sleek and clean look due to the removal the wooden side panels. Boooo!

Aside: I've always wanted to start an urban myth that wooden side panels make analogue synths sound better. The wood interacts with analogue waveforms, absorbing certain higher frequencies, providing a warmer sound. :)

It would make sense that the colour scheme would have been updated when other ARP synthesizers like the Mk 3 Odyssey was released with the same "Halloween" theme. Most sites, like Vintage Synth Explorer and arpodyssey.com put the Mk 3 Odyssey manufacturing start date around 1978, although Wikipedia references it at 1976. I'm more likely to believe 1978.

For comparison, below is a photo of an MK 2 ARP Sequencer from a 2007 MATRIXSYNTH auction post via Flickr, next to a Mk 3 Odyssey image from Wikipedia. Dang they look smart together. Wouldn't you like to have those two sitting beside each other in your studio?

Web pages and posts of Mk 2 Sequencers with model #s are not as common at Mk 1's, but I did find enough references online that lead me to believe that there were only two Mk 2 models available - 1621 and 1623. I couldn't find any reference to model 1622's anywhere online.

• model 1621 at synthfind.com
• model 1621 from MATRIXSYNTH found at Flickr
• model 1623 at synthfind.com
• model 1623 at Tonetweakers.com
• model 1623 at obliq.net (scroll down a bit)

When you compare the front panel layouts of the Mk 1's and Mk 2's, there doesn't seem to be any differences, leading me to believe that they function exactly the same. So, why the different model numbers? Different "batches"? Or changes internally? Design engineers that wanted to torment me 35 years later?

Most likely.

I can't find any references online - and have never been around one, let alone a bunch of different models, long enough to open them up and take a look.

Yup. You heard right. As I mentioned earlier, I came across one for sale. And I turned it down.

Don't judge me. I'm trying to build a Eurorack modular system. I'll blog about that when the Tip Top u-ZEUS flying bus board and other modules finally arrive.

I'll kick myself later.