TBDaits

A 24-engine macro-oscillator voice spanning virtual analog, FM (incl. DX7-style 6-operator synthesis with 3 banks of 32 patches), additive, wavetable, chord, speech, granular, particle / string / modal physical models, and analog drum models — driven by a wrapper-side AHR envelope so held keys sustain and release on key-up.

Available on: Track 12 (Lead2) — selectable alongside Wavetable Osc (default boot host), Mono Synth and TBDings.
Built on: Mutable Instruments Plaits firmware 1.2 (extended 24-engine registry — orange / green / red banks).


Character

TBDaits exposes the full Plaits-1.2 engine set in a single voice. The Model knob picks one of 24 engines; Harm / Timbre / Morph then mean different things per engine (chord type, bank selection, FM index, formant ratio, decay time, …) — the OLED reflects the active engine’s parameter semantics where they’re discrete.

The DX7 engine has 3 instances (banks A / B / C, 32 patches each = 96 total) — sweep Harm to browse patches; the OLED shows A17 / B5 / C30 so you know exactly where you are.

A wrapper-side AHR envelope (Attack / Hold / Release) drives the Plaits LPG so:

  • Held keys sustain for as long as you hold them (real keyboard feel)
  • Decay knob shapes the release tail per key-up across 5 ms .. 8 s (drone mode at the very top of the knob)
  • Velocity scales both amplitude AND DX7 patch-internal timbre routing
  • Sequencer steps still re-attack crisply on every trigger

Stereo voicing

TBDaits is a stereo voice. The left channel carries Plaits’ main OUT signal; the right channel carries the engine’s AUX output — typically a sidekick or by-product of the main signal (a different filter tap, an inverted phase, a noise component, etc.). The mixer’s Pan knob blends between them: pan hard left isolates OUT, pan hard right isolates AUX, centre sums both at full level.

Three engines do not emit a distinct AUX — DX7A, DX7B and DX7C output the same signal on both channels. For these engines the Pan knob behaves as conventional left/right balance only.


Engines (Model knob)

24 engines, registry order. DX7A/B/C are highlighted as the headline FM voicings.

# Label Engine # Label Engine
0 East Virtual Analog VCF 12 Add Additive
1 PhDi Phase Distortion 13 Wtbl Wavetable
2 DX7A Six-Op DX7 — bank A 14 Chrd Chord
3 DX7B Six-Op DX7 — bank B 15 Spch Speech
4 DX7C Six-Op DX7 — bank C 16 Swrm Swarm / Granular Cloud
5 Trrn Wave Terrain 17 Nois Filtered Noise
6 SChr Strings Chorus 18 Part Particle Noise
7 Chip Chiptune (Square Chords) 19 Strg Inharmonic String
8 Dtun Dual Detune (Virtual Analog) 20 Modl Modal Resonator
9 Wshp Waveshaping 21 BD Bass Drum
10 FM2 FM (2-op) 22 SD Snare
11 Frmt Granular Formant 23 HH Hi-Hat

Parameters

The default TBDaits performance macro is organised as 3 pages, ordered for live performance: voicing controls on page 1, envelope-driven dramatic controls on page 2, supportive output settings on page 3.

Voice

The 4 main timbral controls. Model + Harm are adjacent because Harm’s display is engine-aware.

Parameter What it does
Model Engine selector (24 engines — see table above)
Harm Engine-dependent. DX7 → patch number (A1..A32 / B1..B32 / C1..C32). Wtbl → bank (A..A-, 8 banks). Chrd → chord type (oct / 5 / sus4 / m / m7 / m9 / m11 / 69 / M9 / M7 / M). All other engines → continuous tone control (% display).
Timbre Engine-dependent continuous tone control (e.g. wavefolder amount, formant frequency, mod index, brightness, …)
Morph Engine-dependent continuous tone control (e.g. asymmetry, feedback, decay time, filter type, …)

Env

Envelope-driven dramatic controls — the drop / build knobs. All four fed by Plaits’ internal envelope.

Parameter What it does
Decay Release time of the wrapper’s AHR envelope feeding Plaits’ internal LPG (5 ms .. 8 s exponential; drone mode at the very top of the knob holds the envelope indefinitely). The release tail is most audible on engines without strong internal envelopes (East / Phase Distortion / Wavetable / Speech). Percussive and resonator engines (Modal, Particle, Bass Drum, Snare, Hi-Hat) have their own decay shapes baked in — Decay still shapes the LPG, but the engine-internal envelope often dominates the audible tail.
FMod Envelope → frequency modulation depth
TMod Envelope → timbre modulation depth
MMod Envelope → morph modulation depth

Shape

Supportive output settings — set per voice and rarely touched live.

Parameter What it does
Level Voice-internal output gain — applied post-engine and pre-LPG. This is independent of the mixer track level on the Mixer screen: Voice Level shapes how hard the engine drives Plaits’ soft-clipper (affecting timbre / saturation feel), Track Level adjusts the per-track contribution to the master bus (affecting the mix only). Use Voice Level for tone, Track Level for balance.
Color LPG character: VCF (filter sweep) / Mix (blend) / VCA (amplitude only). Mostly-audible on the analog / wavetable / granular / modal / additive engines. On DX7A / DX7B / DX7C the engine’s internal velocity-to-timbre routing overrides the LPG colour input, so Color has minimal effect on those banks.
Freq Pitch detune (±12 semitones) around the played MIDI note

Browse the 96 DX7 patches by selecting Model = DX7A / DX7B / DX7C and sweeping the Harm knob. The OLED reads A17, B5, C30 etc. Lock Harm per step in the sequencer to step through DX7 patches across a pattern.

Crank Decay to the very top for drone mode — the envelope never releases, holding the LPG open indefinitely. Combine with the Noise / Speech / Modal engines for textures that sustain past key-up.

Use FMod / TMod / MMod for performance drama — automate or hand-sweep these for build-ups and drops. Each scales how much Plaits’ internal envelope modulates the corresponding voicing parameter.


Playing TBDaits

With the sequencer: per-step velocity is honored on every trigger (re-attack snaps the envelope to the new velocity). Lock Harm per-step to browse DX7 patches inside a pattern. Lock Model per-step for radical engine switches mid-bar.

With an external keyboard: held keys sustain for as long as you physically hold them — the wrapper’s AHR envelope tracks key-state directly. Velocity drives both amplitude (via wrapper master gain) and DX7 patch-internal timbre routing (via accent). Decay shapes the release tail on key-up.

In the sequencer: each step has a fixed length (Length / Gate setting); at step-end the sequencer emits a NOTE OFF and the wrapper’s release phase begins per the Decay knob. Holding a sequencer step longer does not extend the gate beyond its programmed length — for held / drone notes use Decay = drone-mode (knob top) or play live with a keyboard.


See also

  • Mono Synth — single-engine Braids-based monophonic alternative.
  • PolyPad — chord-pad voice with built-in chord generator.
  • TBD03 — 303-style mono bass.

Origin & credits

TBDaits wraps the Mutable Instruments Plaits firmware 1.2 voice (extended 24-engine registry) for the TBD-16 PicoSeqRack plugin host.

Plaits is © 2018-2021 Émilie Gillet, MIT-licensed (see plaits/LICENSE). Firmware 1.2 adds 8 “orange-bank” engines (Virtual Analog VCF, Phase Distortion, Six-Op DX7 ×3, Wave Terrain, Strings Chorus, Chiptune) on top of Plaits’ original 16-engine palette.

The wrapper around Plaits adds:

  • A wrapper-side AHR envelope so held keys sustain and release on key-up (Plaits hardware default behaviour assumes an external CV envelope on the LEVEL input)
  • Per-engine semantic OLED rendering for HARMONICS (DX7 patch number, Wavetable bank letter, Chord name)
  • A silence gate so drone-style engines (Noise / Speech / Modal at high decay) don’t hum continuously when no notes are playing
  • Per-instance LCG and PSRAM placement-new for the Voice + 16 KB allocator workspace

  • DSP source: plaits/dsp/voice.{h,cc} and the plaits/dsp/engine{,2}/*.{h,cc} engines
  • TBD-16 wrapper: rack/RackTBDaits.{hpp,cpp} (PicoSeqRack)
  • Related reading: Plaits manual