The Leviathan is a Drive + Reverb pedal with two drive voices and two reverb modes.
It's now available as a version with an expression input to control decay time, which in some settings it can also control the self oscillation. The expression pedal resistance should be 10k.
It's started off as being vaguely based on the Death by Audio Reverberation Machine but it's been tweaked, bent and refined and now it's got a ton of mods.
First mod is the decay time. And it's an awesome mod too. The reverb module doesn't have adjustable decay, but it does have an unused stereo output.
So, I feed that back into the input and get some super long reverb decays, and if you crank it right up it will also self-oscillate.
It's kinda a really glitchy and hacky way to adjust decay time but it really sounds awesome and quite unique.
Second mod is the drive voicing. The original pedal has this really grainy low gain drive that adds a ton of colour and a few plosives to your sound.
It sounds almost like surface noise from a worn-out vinyl. I really like it so I left that alone (Sand), but I added another voice that has more gain (Silt).
Silt is based on part of the feedback loop filter from the RAT pedal, but it's used in a completely different way and sounds completely different too.
It's a lot smoother than the sand voice, has better sustain and breaks apart very nicely.
The reverb has bright and dark modes too (Breach and Dive)
You can also disconnect the reverb and use it just as a drive pedal.
This is a really versatile pedal and can go from a standard spring reverb tank, to a over-driven and saturated signal dripping with ambient bliss, create self oscillation or just rock out as a drive / distortion.
Heads up this pedal can be a noisy bastard, due to the digital reverb tank.
There is a little bit of background hiss when the signal is wet and you stop playing.
If having an audible noise floor is a problem, this probably isn't the pedal for you.
IMO it's other qualities well make up for this small flaw.
True Bypass Wiring, Top Jacks, 9V DC Jack (boss style), 9V battery, Lifetime Warranty.
Quick and Dirty Demo of the Expression Version: