If a standalone pedal, I'll pick OD3. Thick and fat sounding. I can survive kahit SS amp. But if I have a good amp or a tube amp, the SD1 is a good booster. The mid hump works well sa solo. OD3 don't have the mid hump going, which is not a bad thing, just a different thing lang.
Pansin ko lang, if you move clockwise the gain knob ng OD3, nadadagdagan pa ang volume. Nice feature. SD1 don't have it.
Here's a demo of both pedals.
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