Part 2 & Building the Two Thousand Six Hundred (TTSH)


The TTSH an Arp 2600 Clone

Part 2, Arp 2600: Hell Breaking loose

In 1983, The US parent company of Garrett Manufacturing/Air Research (Bendix) was purchased by the parent company of Allied, which was merged with Signal and TRW and Kellog-Rust and…. The 80s were not kind to many aerospace companies either. Huge companies were all amalgamated, bought, sold, ripped up in an effort to become competitive. Sometime in the fall of 1985, we became Allied-Signal Aerospace and they closed down the microcircuit division. Engineering, production, repair and spares….. ‘POOF”… gone. I was fortunate, I was only 27 so they moved me to the electronic/avionics controls division as a circuit designer. Many others lost their jobs. Gary Benson, being about 50, was one of them. Meetings and discussions became weekend things, which became monthly things, which became irregular phone calls, and then stopped all together. Our Arp project died. Gary eventually moved to Texas to work for General Dynamics and I never heard from him again.

I still had, 3 completed sets of PCBs, Schematics, Digital PCB files and net lists, hundreds of components, assembly specs & instructions, test specs and tooling for test circuits. I also had a few poly design circuit boards and files for the new CPU and Voltage controller/processor board. Months went by, then years. I got married, had kids and eventually moved to St. Catharines with my family in 1989. The remains of the Arp project lived in cardboard boxes in the basement (along with my Moog clone from 1978), the only board that did not fit was the voltage control/processor board for the intended Arp poly. It hung on the basement workshop wall, in the dark just like the whole project idea and stayed there until 1995.

The summer of 1995 saw a torrential thunderstorm, which dumped almost 10 inches of rain in an hour. Our street and sewer lines backed up, and my basement was flooded with a mixture of raw sewage, mud and rain water, that was 5ft deep. Everything below that water mark, was basically destroyed. There was so much stuff contaminated, we basically threw it all into a giant dumpster and never saw it again. Power tools, electronics, collectables, kids artwork, furniture, freezer, washer, dryer, furnace, water heater, and old Arp projects. The only thing from that project to survive, was the VC Processor hanging on the shop wall, and some components. They were all 6ft above the floor. Gone, what I thought yjen, was a final chance at obtaining an Arp 2600, but truth be told is at that point in time, an Arp or analog synthesizers in general, were just not a priority. I had left work at the aerospace company and re-enlisted back into university. As a student of computer science and artificial intelligence, there was huge potential for all sorts of creative but digital endeavours.

Perspective & Context.

Some people may be getting into their first synths or learning about Arp Instruments in general, or maybe they are building their own TTSH are probably thinking “How could you have thrown all that stuff out, it is worth a fortune”. Nope, it was not worth anything then and it is not really worth anything now. In the late 1990s nobody was interested in analog synthesizers, let alone Arp 2600s. Electronic music sort of dissipated in the 1990s, and nowhere near as prevalent as it was in the 70s and 80s. There were thousands of used synths on the market. There was only the odd person who still had a modular synth, and they probably still had vinyl records, none of which was recorded later than 1983. I still have a commodore 64, and 2 Apple II plus computers, disks, monitors wrapped up in storage bins hoping to make my millions…. Nope, not worth much either.

I mention this because this entire story has to be put into context and has no real evidence to back it up. No photos, no web pages, no books, no video. Back in the day, nobdy carried cameras with them, the internet was only found in universities and large government companies. So this is really just a history from my perspective on what I can remember. Now at 62, close to retirement, I am always asked about analog synthesizers and “how easy it must have been to get one”. Fact is, information was just harder to obtain and you had to be lucky enough to meet people who would share their knowledge. In the next section, this becomes relevant as I do not have anything written from that time. No spec sheets, no drawings, no files, no Arp PCBs, no Arp assembly instructions. So take this with a grain of salt and please do not cite my build rationale as the gospel or absolute truth.

I do have a VC Processor pcb and some hand scribbled notes I found in a plastic bin of other work related drawings. I am using my recollection from the knowledge of another for how I built my TTSH and how I will build the other Arp clones. The fact is, I really have no exact idea of how an Arp 2600 was made. But I do have knowledge of how the industry worked, how electronics companies built things, how analog gear was designed, built and serviced. We did have industry standards, and for the most part they were fairly consistent across the field. I also have a photo, hanging on my wall.

In 1984 I was working over my lunch on the project, when my boss, some marketing people and the Vice-President came into our engineering offices. They were making a 50th anniversary calendar, and wanted some “high tech” images. Back then, our CAD system was indeed high tech. So, they asked me to bring up a couple project files on the screen. I posed with a colleague in some sort of “stupid mansplaining pose” to make it look like we knew what we were doing. Funny thing about CAD system and computers back then… they were not fast loading files as they had to transfer from the main storage to the local storage, then load in the HP workstation. So, the only file I had availible, was the one I was currently working on. The VC processor PCB. Funny how things turn out, I had forgotten all about this until I started writing this post. So, I pulled out my iPhone….

The Author in 1984, a colleague and Zuken / HP CADD system

Currently, there are multiple clones and reissues for an Arp 2600. I personally think, that there is now a flood in the market place and it will eliminate the mystique for this synth, and most likely others as well. You can buy one from Behringer, which will sound somewhat the same for many patches. But it is not 100% analog either, it has a digital reverb unit which is definitely going to change the tone. Also, I doubt patching CV into the digital reverb will do the same funky stuff patching CV into a spring reverb will do. Korg (which purchased Arp) also has a re-issue which is 100% analog (except the MIDI implementation). In order to be production worthy in today’s market place, both Korg and Behringer use modern equivalent components like transistors, capacitors, and op amps.

The LM301 used in original Arps are still available (and inexpensive), but some of the older JFets are not around, or are so scarce or expensive, using them commercially would make the price point too expensive for consumers. The TTSH however, has been a DIY project that has been around for several years now, has gone through multiple revisions and allows the builder to use older components if they wish. This fact was why I chose to build a TTSH, as it would allow me to use the older components like MC1539G op amps which were used in the Blue Marvin version. Or, allow me to experiment with other Op amps of the same period that were better than the LM301. Like the LM218, LM201, and AD711. Most of all I could build it knowing about production specs and techniques Gary Benson talked about all those years ago. Because other than layout, the TTSH circuits are pretty much identical to an original Arp 2600. Saves a ton of time relaying out PCBs on a CAD system. That is for sure!

I did not intend to build a TTSH for myself. I actually got involved in another project that would have been a 1:1 identical clone of an Arp 2600. Specifically, it would have used really high-end audio components and even some OEM parts. In fact, this particular project (call it the LS Arp), was so close to the original you could swap out circuit boards with a real Arp, and everything would have worked fine. With Behringer releasing a “consumer grade” Arp 2600, I just do not see demand for the TTSH anymore. There is also rumour that Korg is releasing a reduced size “consumer grade” version as well. Given that and waiting two years on the LS Arp to still be completed, I decide to build TTSH for myself, while they were still available.

The TTSH Build

Arp 2600 Part 1

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