by Taylor Livingston » Mon Jan 03, 2022 5:07 pm
I saw your post on TB and hopefully some users will give an answer from a player's perspective. But I can give an answer from a co-designer's perspective. They are actually completely different circuits under the hood. The Subterranea is analog and the Dubterranea is digital. For that reason, there are some people who still prefer the Subterranea despite it having fewer features and some quirks.
The Subterranea's synth voices can't really be turned off. Even if you turn the volumes for them down all the way, they'll bleed through a little bit. Since it was meant to be paired with a filter, that's not really relevant when the filter is on. But for people who want to use it without a filter, and want a normal octave sound without high harmonics, that was an issue, and something that caused many people to email me thinking their Subterranea was broken, and that's among the reasons I stopped building it. If you've already been using it for years though, you're familiar with its quirks.
The Dubterranea doesn't have that issue. You can turn off the synth voices with a stomp switch, allowing you to use it both as a synth pedal and an octave pedal without fiddling with knobs. It also has an octave up, which the Subt doesn't. It has more variety in sounds, more accurate waveforms (a sawtooth that actually sounds like a sawtooth and has the proper harmonic balance), a triangle wave that can be good if you want something less buzzy, and more variation in the Octaver voice's timbres. It also has an effects loop/expression jack which lets you control the synth voice volume with an expression/volume pedal, or apply effects only to the synth voices and leave your clean and Octaver channels unaffected.