DRIVE, OD and FUZZ

DRIVE distorts the input before anything else. The OD / FUZZ switch under the DRIVE knob picks the character of the distortion. DRIVE defaults to 15% and the voice to OD.

Where it sits

DRIVE comes before the dry tap, so it colors both the dry and the processed signal and is heard at any MIX setting. With DRIVE at 0 the stage is bypassed completely. Fades between the two voices and in and out of DRIVE take about 10 ms.

DRIVE runs at four times oversampling and adds 14 samples of delay. Bent Spool does not report that delay to the host. Level is matched across the knob, so turning DRIVE up does not make the output much louder.

OD

OD is a soft overdrive in the style of a tube-screamer pedal. The low end bypasses the clipper, so bass stays intact while the mids and highs saturate. Gain goes up to about 30 times. The clipping is slightly asymmetric, and the clipped part is filtered more darkly as DRIVE goes up: from about 9 kHz at the bottom of the knob to about 2.6 kHz at the top.

OD is free on iPhone and iPad.

FUZZ

FUZZ is a harder distortion. It high-passes the input at 250 Hz, applies up to about 80 times gain, blends in octave-up content from rectification, and clips it asymmetrically. A low-pass sweeps from about 7.4 kHz at the bottom of the knob to about 2.3 kHz at the top. There is no dry path inside FUZZ, since the fuzz is the signal.

Sputter on decay

As a note decays, FUZZ starves. When the input falls well below its recent peak, by 30 dB at low DRIVE and 16 dB at high DRIVE, the fuzz starts to sputter, tears into crackle and then stops. The point where this starts does not depend on how hard you played the note. Higher DRIVE shortens the sustain, from about 3.9 seconds at 10% to about 2.8 seconds at 100%, according to the engine's own measurements. The sputter is not random and does not respond to CHAOS or the seed. Quiet material below about -70 dBFS is cut off.

On iPhone and iPad, FUZZ is part of the unlock. Without it, FUZZ plays as OD.

Fuzz tremolo

FUZZ works in any mode. The factory bank has eight FUZZ TREM presets, which are TREM with the FUZZ voice. See Factory presets.