Drum

Module ID source.drum · Category Source

Drum Module A kick just after a hit. The orange line is its pitch, falling two and a half octaves to 48 Hz in the first few milliseconds. The blue curve is its level, lit up to the playhead.

Drum is one analog drum voice. Its Type turns it into a kick, snare, tom, clap, closed hat, open hat, cymbal, rim, cowbell or shaker, each built the way an 808 or 909 builds that sound: a few oscillators, a noise source, filters and decays. Send it a trigger and it plays one hit.

The same five knobs serve every type, and each means what it would on that drum's own panel. Tune sets the pitch of a kick and the metal of a hat. Snap sets a kick's beater and a snare's wires. The names never change, so a MIDI mapping keeps working when you change the Type.

Drum is polyphonic. A polyphonic gate, from Note In say, plays a new voice for each note, so fast hits ring on over each other instead of cutting each other off.

The types

Each type has its own pitch, its own range of decay, and its own meaning for Tone and Snap. The times are how long a hit takes to fall 60 dB, from Decay at 0 to Decay at 100%.

TypeBuilt fromTune 0DecayToneSnap
KickA sine that falls in pitch, and a beater click48 Hz0.12 – 2.5 sDrive, from a pure sine to a rounded, 909-like thumpHow far the pitch falls (half an octave to four) and how hard the beater clicks
SnareTwo drumhead tones, and noise for the wires185 Hz0.08 – 0.8 sThe wires, from dull to brightWires against the drum: more rattle, less tone
TomA sine that falls half an octave, and a stick click110 Hz0.12 – 1.8 sDriveThe stick on the head
ClapFour bursts of noise a few milliseconds apart, then a tail1150 Hz bandTail 0.08 – 1.0 sNarrow and dark to wide and brightThe bursts against the tail
Closed HatSix square waves at the 808's inharmonic ratios, ringing in a band around 6 kHz, with hiss above it205 – 800 Hz squares25 – 300 msWhere the band sits, and how much air is over itHiss against metal
Open HatThe sameThe same0.15 – 1.8 sThe sameThe same
CymbalThe same squares through a low and a high band, a bright splash over a long washThe same0.6 – 5 sFrom the low band to the highSizzle against metal
RimTwo tones, 1667 and 455 Hz, and a crack of noise1667 Hz15 – 200 msDriveThe crack
CowbellTwo squares a sixth apart, through a bandpass540 and 800 Hz0.1 – 1.2 sThe bandpass, dark to brightThe clank of the strike over the ring
ShakerA band of noise that swells in over 3 ms, as the beads arrive, rather than striking6.7 kHz band40 – 200 msWhere the band sits, from 5 to 9 kHzThe rattle: the beads landing unevenly inside each grain

The hats' six squares run all the time, as the 808's do. They are never caught at the same place twice, so no two hits sound exactly alike.

Every other type starts at full level the instant it's struck. The Shaker's grain swells in, because the beads in a shaker don't all hit the wall at once. Accent shapes that as a wrist does: a full shake swells in over 3 ms, and a soft one over as much as 8 ms, as well as being quieter and darker.

Inputs

PortSignal TypeDescription
TrigGate (Green)A rising edge strikes the drum. Patch a sequencer's Gate, a clock, or a MIDI gate
AccentControl (Orange)How hard each hit is, from 0 to 1, read as the hit lands. Patch a sequencer's Velocity. Unpatched, every hit is full
ChokeGate (Green)A rising edge damps the drum within 5 ms. A choke that arrives before a hit does nothing to that hit
TuneControl (Orange)V/Oct, added to the Tune knob at each hit: 1 V is an octave
DecayControl (Orange)Added to the Decay knob at each hit

Outputs

PortSignal TypeDescription
OutAudio (Blue)The drum. At default settings a full-accent kick peaks around -4 dBFS, and the hats and the rim sit a few dB lower

Parameters

ControlRangeDefaultDescription
TypeKick … ShakerKickWhich drum. The knobs keep their settings when it changes
Tune±24 st0 stPitch in semitones from the drum's own
Decay0 – 100%50%How long it rings, over the type's own range
Tone0 – 100%50%Dark to bright, as the table describes
Snap0 – 100%50%The noise or click in the hit, as the table describes
Level0 – 100%80%Output level

Tune, Decay, Tone and Snap are read when a hit lands, as on a drum machine. A hit keeps its sound however the knobs move while it rings, and the next hit takes the new settings. Level follows the knob at once.

Accent

Accent scales the hit's level, so at 0.4 it plays 8 to 10 dB quieter, and at 0 not at all. A softer hit is also darker and less snappy, as on a real drum: Tone drops by up to a quarter and Snap by up to half, and a soft kick falls a little less far in pitch. A ghost note on a snare is a different sound from a backbeat, not just a quieter one. While Accent is patched, the Tone and Snap knobs show this. An orange arc on each runs out to a bead at what the Accent makes of it, and the number under the knob reads that value in orange.

Choke

A hi-hat is two drums that can't ring at once: closing the pedal stops the open hat. To do this, patch the closed hat's trigger into the open hat's Choke as well as its Trig:

[Closed lane Gate] ──> [Drum (Closed Hat) Trig]
                  └──> [Drum (Open Hat) Choke]
[Open lane Gate]   ──> [Drum (Open Hat) Trig]

The open hat rings until the next closed hat lands, then dies in a few milliseconds, the way a drummer's foot shuts it. Any gate can choke any drum: a kick that chokes a long cymbal makes a cut-off crash.

A voice struck again while it's still ringing starts the new hit at once. It lets go of the old one over a millisecond or two, so a fast roll on a long kick doesn't click.

The display

The display draws the hit the knobs will play next. The blue curve is its level. Time runs on a warped axis that is wide at the start, so a kick's 10 ms drop and a cymbal's five-second wash both fit, with faint marks at 10 ms, 100 ms and each second. The ring time is at the top right.

The orange line is pitch. For a kick, snare, tom or rim it is the fall from the strike to the drum's resting pitch, which is printed at the top left. For the hats, cymbal and cowbell it is one line per square wave, each fading as the ring dies. For a clap or a shaker it marks the band the noise rings in, and the shaker's level curve rises from nothing as its grain swells in.

When the drum is hit, the fill flashes, and a playhead travels along the curve, lighting it as it goes. The lit curve is as tall as the hit's Accent, so ghost notes and backbeats read at a glance. A choked hit drops to nothing where the choke caught it. Hover the display for the numbers.

Patches

A kit in a few modules

The Drum Machine example is a whole kit in 14 modules: a Clock, five sequencer lanes, five Drums, a Mixer, a Reverb and the Output. Each sequencer's Gate goes to its Drum's Trig and its Velocity to Accent.

Tuned toms, or a cowbell melody

[Sequencer Pitch]    ──> [Drum (Tom) Tune]
[Sequencer Gate]     ──> [Drum (Tom) Trig]
[Sequencer Velocity] ──> [Drum (Tom) Accent]

Each step's note sets the tom's pitch, with middle C at the Tune knob's pitch. Set the Type to Cowbell for the classic 808 cowbell line, or to Kick with a long Decay for an 808 bass.

A layered snare

Patch one sequencer's Gate into two Drums, a Snare and a Clap, and mix them. The clap's bursts sit on top of the snare's crack. Turn the clap's Snap down so only its tail comes through, as a short room.

Rolls and flams

From a Note In module with several voices, two notes very close together each get a voice, so a flam rings as two hits rather than one cut short. A Clock at 1/16 with a high Swing into Trig makes a shuffled roll. Patch a falling envelope into Decay and the roll tightens as it goes.