Power that OCD at 18v for maximum awesome! Gives it more depth and headroom; hard to describe; other than; to me, sounds way better at 18v instead of at 9v.. Also; try putting a tube screamer after the OCD to act as boost and tone shaper. Gives more impact post OCD; as opposed to before. I just got a mini Tube Screamer; I love it! Sooo tiny. I have a Keeley modded TS9 too; they can be dialed in similar; the Keeley mod has something additional in the gain range; but the mini is quite impressive for the size!