Mach 1: "Swift Overdrive"

rwl

Member
Build Rating
4.00 star(s)
This is a build of the Mach 1 Overdrive, based on the Greer Lightspeed Overdrive. This is a pretty transparent overdrive and the board is simple.

Since the theme of both pedals is speed, I decided that a good namesake bird would be the Swift (specifically a Common Swift), which is literally a bird named for its speed. The Swift is remarkable: it's the fastest bird in level flight, flying up to 70 miles per hour. And it can fly for 10 months at a time. It's adapted to have very short legs that it only uses to cling to ledges.

It isn't my favorite design on the front. I realized I had 9 UV prints ordered on Tayda and a 10th would drop the price of the UV prints and gloss as part of a batch discount, so I designed this one in an hour or two to round out the order. That said, it's not bad. It's printed on a sky blue background.

The build was relatively simple, and when I tested it with dials around 12 o'clock prior to boxing, I was satisfied - it was a nice clear volume boost. But once I had it in the enclosure and started playing around with the settings, I found that there was almost no gain with the drive knob all the way up. There was a faint amount of crunch but it almost sounded hollow or echoey, nothing like any of the demos. I was lucky in two ways. I found a few threads on the forum indicated problems with the OPA2134 chip... and for the past 10 pedals or so, I've socketed all my ICs (after I found out sockets were cheap and easier than soldering the ICs themselves). I auditioned a TL072 and a JRC4558D and found I liked the 4558 best. As I was swapping the chips I tried the OPA2134 again and it seemed to work ok this time - it must have been seated poorly. Even so, I returned to the sound of the 4558.

With all that said, I can't help feeling there's something wrong with the build or I'm not using it right. Unity on the volume control is about 1 o'clock, and without a loud pedal running into it, the drive is still modest, and there's a moderate hiss with the drive knob all the way up.

I've got a few questions for folks, if you're reading this:
1. Any suggestions for how to use this pedal? With knobs at noon it's a nice transparent sound, but I don't find it very versatile overall. Or maybe I messed up something obvious?
2. Are there any cheap, easy-to-use sockets for transistors? I'm realizing I should probably socket more to be able to play around with the builds that don't impress me (since I don't currently do much breadboarding). 8-pin dip sockets on Tayda are 3 cents, meanwhile transistor sockets are $1.75. I've seen recommendations to cut up the strips of male-female adapters, which are cheap, but that's a lot of work and I always seem to cut the plastic wrong and leave the pin partly or fully exposed.
 

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