Another Dimension

Details

A while ago, I built a Monotonous Delay. It’s a modulated delay using dylan159’s Pelota circuit with a couple extra bells and whistles. I was aware of a Pelota variant that is a triple threat: delay, chorus, and vibrato. A chorus is basically the same thing as modulated delay, just with a delay time set so short that the repeats can’t really be heard as individual echoes. Remove the dry signal from that and you’ve got vibrato. Keep the delay time to where each repeat can be distinctly heard and you have modulated delay. dylan159 has openly questioned whether or not it can actually do chorus. The Pelota uses a PT2399 delay chip, which can’t go much below 30ms of delay time, and in practice has to be set higher than that to get it to modulate. That’s a bit long for traditional chorus, and sounds like half chorus/half slapback echo, but it’s still interesting and on par with other choruses that use the same IC.

Then there’s the Dimension-C. As with many pedals, I assumed a Dimension-C was impossible to build at home—full of bucket brigades and black magic. But I still wanted one, and wound up researching them to figure out how they worked. As soon as it clicked that it was two modulated delays with the modulation inverted on one, I wondered if I could do it with two Pelotas taped together. In the time since I’d built the Monotonous Delay, dylan159 had come out with a revised version, the Pelota 2. There was no vero layout for it, but it had a lot in common with the previous version, and I figured I could make it work.

That turned into an odyssey. I spent months on it. It was so over my head that I paused and built the Slow Danse Macabre in the middle, since the schematic and layout for that already existed and I’m much better at executing a recipe than throwing a bunch of random crap together and declaring it a souffle. The Slow Danse is the same concept as my Double Pelota idea, but without all of the filtering and careful tuning—the Pelota is heavily focused on sound engineering, in both senses of that term. While I was grinding through the circuit, I would occasionally share my in-progress schematics with my pedal peeps and they would point out several things that were wrong with it. I’d fix them and present it again, and there were always still a few things that could be improved. I finally decided to just build and see what would happen.

And it didn’t work. The pedal cognoscenti helped me troubleshoot the assembled board over the course of weeks, and I found a few things on my own. One of my TL072s was bad, which took some meticulous voltage sniffing to find—it seemed far more plausible that there was a problem with my circuit than with the components. I found an error where I was supposed to use a 4.7nF capacitor and actually used a 4.7μF, which is off by a factor of a thousand. It’s so rare to be that far off and not notice. Like if I went to the deli for a pound of cheese and accidentally got a thousand pounds, I feel like it would stand out, but it’s an easier mistake to make with capacitors. When I finally got both sections of the delay working, it became clear that the mixer section was distorting. I had to resort to math to figure out how to calculate the gain of an “Inverting Summing Amplifier,” but I got it going.

Another Dimension’s controls are Speed and Depth, which adjust the LFO like on a traditional chorus. There’s also a toggle to remove one of the choruses from the circuit, which makes it sound like a classic warbling chorus. Most importantly, it works. Special thanks to dylan159 and aotmr for helping me get through it.

Sound

As configured, I would say that it does not come as close to the platonic ideal of the Dimension-C as my Slow Danse Macabre does. It can produce a version of the Dimension-C sound at certain speed and depth settings, but it’s a little finicky about it and the effect is perhaps not as prominent. It’s got a lot more slapback delay than I was expecting (despite dylan159’s plain warnings), which could be a benefit to some, but is not my thing—it mostly makes me want to check the latency on my audio interface, even when I’m playing through a physical amp. It can probably be further improved, but I needed to package it up and call this version “done” to un-mortgage my head space.

None of this is to imply that I’m disappointed. This is the most complicated pedal I’ve ever built by a wide margin, and the design and layout was on a scale that I’ve never attempted. I’m excited that it works at all. It may turn out that it pairs better with another effect or fills its own unique niche. One interesting discovery is that when cranked up, it will do a quasi-Uni-Vibe/ultra-fake Leslie sort of thing that I was not expecting but enjoy. I’ll mess with it.

The following sample is in three parts:

• Part 1: Emomaster > Smewthe Compressor > Another Dimension > Fender Deluxe. The chorus is on a reasonably motionless setting, then overlaid with a second guitar using the same chain but with the Another Dimension pushed into bobo Uni-Vibe mode
• Part 2: The same chain but with the second delay line bypassed for a more standard chorus sound
• Part 3: I wanted to see what would happen in combination with a ludicrous effect, so this is Emomaster > Toynbee Fuzz/Envelope Filter > Fender Deluxe, and it goes to a whole ‘nother dimension

---