The Last Project

I picked up an old Arp Odyssey recently.

Arp Odyssey

It was one of those snap eBay purchases – a synth listed just moments before with a Buy-It-Now price that seemed unusually low. I’ve made a lot of those types of purchases in the last couple years. It all started with an Oberheim OB-1 that I got for $300 (plus the seller wound up throwing in a semi-functional SH-101 for free). I’m not a gambling man (or at least casinos and lottery tickets don’t really phase me), but the thrill of that split-moment decision became a little addictive.

I began watching eBay listings in most of my spare moments. I bookmarked the page of newly-listed analog synths and made a habit of routinely checking it. I’d check in the grocery aisle, on the L, at a stop light, or during breakfast. Checking at a rate of about a dozen times a day, a good deal seemed to show up every two to three months. Sometimes I was a little trigger-happy and wound up with a purchase I wished I could take back. But once I got a TB-303 for $150. That was certainly the high point, heartily nudging out the OB-1 snag from its gloried throne. I’ve bought two Minimoogs, a Matrix 12, an AKG C414, a Roland RS-09, a TR-808 and probably a few other odds-and-ends using the same technique.

Sometimes the items are in pretty-much perfect shape (like the 303 or 808). But most of the time, there’s a lot of repair work needed. The two Minimoogs required re-bushing the keyboard, heavy cleaning, some moderate electronics repair work and, for one of them, a new wooden case. The OB-1 had some filter issues but, more alarmingly, actually had a piece of the case sawn off. I ultimately had to find a local welder who specialized in aluminum welding. The Odyssey falls into this later category of synths. It’s in sad shape. Like the Minimoogs, the uneven keys are a tell-tale sign of needing new rubber bushings. A couple of the sliders are snapped off. The case seems to be missing all but one lonely screw. I believe it powers on but I think the seller claimed that it “makes funny sounds”. For an analog synth, that could mean anything from “totally broken” to “works like usual”. For the price, it’s probably still worth all the work. But lately, repairing broken down gear feels like all I do anymore.

This blog is actually a nice illustration of how I feel at the moment. I started it out in that great blog tradition of just wanting to meander about the subject and share what I’ve been up to. I thought I’d perhaps post semi-completed songs or talk about what excites me about certain pieces of music. Instead, the blog has veered deeply into the subject of my latest gear acquisition, and how I’m in the midst of repairing it.

So I’m trying to take a step back from repairing synths. And more broadly, from buying synths. And perhaps even getting rid of some synths. I suppose that calling the Odyssey “the last project” was a bit melodramatic. I still have a number of items that I intend to fix up (I’m looking at you, Lexicon Prime Time). But I’m trying really hard to stop this behavior of gear acquisition. At least for a little while.

Bit One Mission Successful

I’ve had a broken Crumar Bit One synth sitting around for about a year now. This last week I finally got it fixed up and it’s already on its way out the door (courtesy of eBay).

Crumar Bit One

I bought this from a guy in Chicago last summer. I was heading to Chicago for an old roommate’s wedding and I noticed the synth on Craigslist. I emailed the guy and we started trying to figure out the logistics of meeting up. Apparently I mentioned that I was in Michigan and he immediately grew very cautious and said that the synth likely wasn’t worth driving down to Chicago solely to see and that it had a few problems. I told him I was heading that way anyway and left a little early to make a slight synth detour.

Everything was fine, but occasionally a note would sound sort of weird. The seller wasn’t a keyboard player and wasn’t really sure what was going on. I noticed that this was only happening to every sixth note, and it sounded like the filter simply wasn’t being applied. The Crumar uses Curtis chips for its filters, so I hoped that maybe one of the chips was just bad. I figured out which Curtis chip was tied to the faulty voice and tried swapping in another chip but the problem remained. At that point I got busy with other stuff and the synth sat around all winter. Resolving to finish it up, last week I got it back out and opened it up.

Bit One - Workbench

I don’t have an electronics background and I feel like I’m over my head whenever I start poking around at the circuits. But I’ve watched my friends Kris and Jon (both gentlemen who have a much stronger grasp on electronics theory) troubleshoot circuits and I’ve gleaned that sometimes it’s better to just try to follow your gut, and swap parts out for a true empirical test. I think I’ve erred on wanting to conclusively prove that a resistor or diode was bad before I replaced it. Sometimes it’s better to just have a hunch and then test out that hunch. So in this case, I started measuring voltages around the Curtis chips and found that the voltages coming out of a couple op-amps were far different than all the others. I’ve seen old 70s vintage op-amps fail a couple times in other synths, so these seemed like worthy suspects. A quick trip to Radio Shack and I had two new op-amps installed.

Sure enough, that fixed the filter issue. Apparently one or both of these guys were bad:

The Culprits

I cleaned up a few more little things on the synth and then listed in on eBay. It’s a cool synth and I like it. But these days I’m trying to focus on using my Matrix 12. I’ve trying to narrow my focus a little, so I need to thin out the herd a little. Hopefully this will find a new happy home somewhere!