Comes stock as a Tubescreamer-type pedal, but with some modifications to the circuit to change the sound in a matter that I like. Even though it sounds great stock, it has too much compression on the tone, the bass response needs some improvement, and when used for extensive overdrive it becomes too thin of an overdrive and wimpy.
I modify them to have more increased output, a more touch-sensitive response, and a more complex gain character. The bass is far more stable than when stock and retains clarity at all settings. No matter what music it is used for, my modded SD-1 ALWAYS delivers far more than I could ever hope or expect from it.
I've had this thing forever. It's a multi-fx unit and I use it mainly for extra modulations or delays and reverbs. It's a very affordable Whammy IV, just in a different box.
I'm still trying to replace it with either a Digitech EX-7, Digitech Reverberator XP-400, or (more favorably) a Yamaha Magicstomp UB99. I really LOVE the Magicstomp, it's so impeccably unique and wonderful.
(But, it looks more and more everyday like I'm just keeping the RP80.)
There's too much to say about this one. My first real Delay pedal. Has 11 different modes, at first glance, but once you know this thing there's almost nothing that it can't do.
Also my very first looper. THAT lead to really all my songs, since pretty much all of them have loops. :)
Much thanks to Big Pawn in Clinton for this one. I walked in and found it broken. Took it home and fixed it. Possibly my favorite digital delay, even though the old-school quality of the memory chips adds some noise, it also adds a great flavor to it. It's really impossible to explain.
Line 6 MM-4:
A GREAT modulation pedal. I really like the chorus models on it. The Tremolo has me hooked, but the choruses are my main squeeze of it. The ring mod and pitch vibrato are fun, and plenty of other cool simulations on it. I do like the rotary speaker sound, but IMO the RP80 does it more like the way I like it.
Very nice looper. Multi-function and storeable presets. Also cool to record songs when I'm not in my recording room.