Harmonic Pressure

Harmonic Pressure — 14 HP

Harmonic series pitch CV generator, and the tuning source the rest of the system is built around. It emits a polyphonic V/OCT where every channel is one partial of the harmonic series above a root — no quantiser, no scale table, just the ratios themselves. Patch it into String Mass Core or DroneClone and the mass tunes itself.

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Sound in 60 seconds

1. Add Harmonic Pressure and String-Mass-Core. Patch V/OCT OUT → String Mass Core V/OCT IN, and its OUT to your interface.
2. Harmonic Pressure starts at PARTIAL 1, COUNT 8, TUNING JUST — eight partials of the harmonic series.
3. You hear a stack built on pure ratios. Nothing is tempered.
4. Raise PARTIAL to 4. The stack starts on the fourth harmonic instead of the fundamental — the same series, higher and tighter.
5. Turn TUNING to EQUAL. Every partial snaps to the nearest 12-TET semitone and the stack loses its lock. Turn it back.

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Signal flow

V/OCT IN (root) ──► + PITCH offset (±2 Oct)
                          │
                          ├─ partial n = PARTIAL … PARTIAL+COUNT−1
                          │  voct(n) = root + log2(n)
                          │
                          ├─ TUNING JUST:  exact ratios, untouched
                          ├─ TUNING EQUAL: each partial rounded to
                          │                 the nearest 12-TET semitone
                          └─ TUNING MICRO: JI plus a deterministic
                                            per-partial offset
                          │
                     + SPREAD ensemble detune
                          │
                          ▼
              V/OCT OUT — COUNT polyphonic channels

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Controls

Control	Range	Default	What it does
PITCH	−2 to +2 Oct	0	Octave offset applied to the root before the series is built
SPREAD	0–100%	0	Per-partial ensemble detuning. In MICRO it sets the offset magnitude
PARTIAL	1–16	1	Which harmonic the series starts on. Snaps
COUNT	1–16	8	How many partials, and therefore how many output channels. Snaps
TUNING	JUST / EQUAL / MICRO	JUST	How the partials are tuned. Snaps

PITCH and SPREAD have an attenuverter (−1 to +1) and a CV input. PARTIAL, COUNT and TUNING are knob-only.

The three tuning modes

Mode	What it does
JUST	Exact harmonic-series ratios — pure just intonation. The partials lock and beat against nothing
EQUAL	Each partial rounded to the nearest 12-TET semitone. Use when the stack has to sit with equal-tempered material
MICRO	Just intonation plus a deterministic per-partial offset, sized by SPREAD. Simulates an ensemble that is nearly, but not quite, in tune

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Ports

Port	Direction	Notes
V/OCT IN	Input	Root pitch. The series is built above this
PITCH CV	Input	Octave offset, via its attenuverter
SPREAD CV	Input	Ensemble detune amount, via its attenuverter
V/OCT OUT	Output	Polyphonic — one channel per partial, COUNT channels wide

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Patch recipes

The intended pairing. COUNT 8, PARTIAL 1, TUNING JUST into String-Mass-Core at MODE HARM, MASS 8. Eight partials, each carrying eight voices. This is the patch the whole system was designed around.

Upper-partial shimmer. PARTIAL 8, COUNT 8, TUNING JUST. Starting high in the series gives closely-spaced intervals — a shimmer band rather than a chord. Feed DroneCore for a cheap, bright stack.

Detuned ensemble. TUNING MICRO, SPREAD 40%, COUNT 6. Each partial sits slightly off its true ratio, and the offsets are deterministic, so the detuning is stable rather than drifting.

Moving root. Drift STEP output → PITCH CV at attenuverter +0.5. The whole harmonic series transposes in steps while keeping its internal tuning intact.

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Known pairings

Module	Routing
String-Mass-Core	V/OCT OUT → V/OCT IN. The primary destination
DroneClone	V/OCT OUT → V/OCT IN for harmonic-series chord walls
DroneCore	V/OCT OUT → V/OCT IN; each channel gets its own detuned pair
Drift	STEP or SMOOTH → PITCH CV to move the root

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See also

String-Mass-Core · DroneClone · DroneCore · Music-Theory · Playbooks

Full parameter spec: docs/modules/HarmonicPressure.md