TREM¶
TREM is a tremolo. It raises and lowers the volume in a repeating pulse. It is the mode every install can use, including the free tier on iPhone and iPad.
TREM only ever dips from full level. The loudest point of the pulse is the original level, and DEPTH sets how far down the quiet point goes.
Controls¶
| Control | Where | What it does in TREM |
|---|---|---|
| RATE (centre knob) | Face | Pulse speed. Free: 0.5 to 12 Hz, shown as 2.4 Hz. With SYNC on, one pulse lasts one note length, from 1/1 to 1/64, including dotted notes and triplets. |
| SHAPE | Face | The pulse waveform. See below. |
| DEPTH | Back | How deep the dips go. |
| PHASE | Back | Offsets the right channel from the left, 0 to 180 degrees. |
| CHAOS | Face | Makes the pulse drift, skip, hang and break up. See below. |
| SYNC | Face | Lock the pulse to the host tempo. |
Everything else (DRIVE, WEAR, MIX, LEVEL) works as described in Signal flow.
SHAPE¶
SHAPE moves continuously through four waveforms, spaced evenly along the knob:
| Knob position | Waveform | Sound |
|---|---|---|
| 0% | Sine | Smooth swell. |
| 33% | Triangle | Even rise and fall. |
| 67% | Pluck | Sharp attack on the beat, then a curved release over most of the cycle. |
| 100% | Square | Hard on and off. The edges are about 6 ms long, so there is no click. |
Between those points the shapes crossfade. The default is 30%, which sits between sine and triangle.
DEPTH¶
DEPTH 100% lets the pulse fall to silence. At 50% the quietest point is half level. At 0% there is no tremolo at all. The default is 100%.
PHASE¶
PHASE delays the right channel's pulse. At 0 degrees both channels pulse together. At 180 degrees the left is at its loudest when the right is at its quietest, which gives a left-right chop. Use a stereo output to hear it. The same offset is applied to the right channel's vibrato from CHAOS.
Sync and the beat¶
With SYNC on, one pulse lasts the note length on the readout. If your host's transport is rolling, the pulse peaks line up with the beat. Bent Spool corrects toward the beat gradually and never jumps. With the transport stopped, the pulse free-runs.
TREM's synced stops run from 1/1 up to 1/64. At 120 BPM that is 0.5 Hz to 32 Hz, which is faster than the free-running maximum of 12 Hz.
CHAOS in TREM¶
CHAOS in TREM acts once per pulse cycle:
- Rate and depth drift. Each cycle's speed can wander by up to 35% and its depth by up to 25%.
- Skip. Some cycles barely pulse: the depth for that cycle falls to 15% of its setting. The chance rises with CHAOS, up to 12% per cycle.
- Stall. The pulse freezes in place for half a cycle to a cycle and a half, then resumes. Up to 8% per cycle.
- Vibrato. A slight pitch wobble that follows the pulse, up to 1.2 ms of delay modulation, growing with the square of CHAOS.
- Sputter. Above 50% CHAOS, occasional bursts of 120 to 200 ms where the depth flickers at random.
- Held pulses. Above 70% CHAOS, a cycle may be replaced by 1 to 4 evenly spaced pulses. At 100% this happens every cycle.
At CHAOS 0 the pulse is perfectly regular. The same seed always gives the same pattern of events.