pulp::signal::drum::VelocityResponse Struct Reference

How hard a hit changes the sound, beyond changing how loud it is. More...

#include <velocity.hpp>

Public Member Functions
float	gain (float velocity) const
	Amplitude multiplier for velocity in [0, 1].
float	bend (float velocity) const
	Pitch-envelope depth to add, in octaves.
float	brightness_scale (float velocity) const
	Multiplier to apply to an exciter or filter frequency.
float	noise_shift (float velocity) const
	Amount to add to a body-versus-noise balance in [0, 1].

Public Attributes
float	level_db = 18.0f
	Attenuation at velocity 0, in decibels below a full-velocity hit.
float	bend_octaves = 0.0f
	Extra pitch-envelope depth at full velocity, in octaves.
float	brightness_octaves = 0.0f
	Extra exciter brightness at full velocity, in octaves of filter corner.
float	noise_balance = 0.0f
	Shift toward the noise layer at full velocity, 0 to 1.

Detailed Description

How hard a hit changes the sound, beyond changing how loud it is.

Velocity that only scales amplitude is the single most common reason a synthesised drum sounds synthetic. A real drum struck harder is not the same sound turned up: the head deflects further so the pitch bends further before settling, the stick excites more high partials, and the balance between the body and the noise the strike makes shifts toward the noise. Turning one knob cannot reproduce that, which is why this struct exists and why every voice in this namespace consumes it rather than reading velocity directly.

All four responses are zero-cost when left at their defaults except level_db, so a voice that genuinely wants level-only velocity says so by leaving the others at zero rather than by omitting the wiring.

There is deliberately no decay term. Velocity must not shorten a note: a soft hit is a shallower swoop of the same length, not a shorter one. A voice that genuinely wants velocity-dependent decay has to expose that as its own explicit parameter, so it is a stated design choice rather than something that arrives as a side effect of this struct growing a field.

Bend depths are meant to convey tension, not portamento: a fraction of an octave is the house default, and the one voice that goes to 1.5 octaves (the Simmons-style tom) is being extreme on purpose, because the laser sweep is that instrument.

Member Function Documentation

bend()

float pulp::signal::drum::VelocityResponse::bend ( float velocity ) const

inline

Pitch-envelope depth to add, in octaves.

brightness_scale()

float pulp::signal::drum::VelocityResponse::brightness_scale ( float velocity ) const

inline

Multiplier to apply to an exciter or filter frequency.

gain()

float pulp::signal::drum::VelocityResponse::gain ( float velocity ) const

inline

Amplitude multiplier for velocity in [0, 1].

noise_shift()

float pulp::signal::drum::VelocityResponse::noise_shift ( float velocity ) const

inline

Amount to add to a body-versus-noise balance in [0, 1].

Member Data Documentation

bend_octaves

float pulp::signal::drum::VelocityResponse::bend_octaves = 0.0f

Extra pitch-envelope depth at full velocity, in octaves.

A harder strike deflects the head further, so the pitch starts higher and falls through a wider range.

brightness_octaves

float pulp::signal::drum::VelocityResponse::brightness_octaves = 0.0f

Extra exciter brightness at full velocity, in octaves of filter corner.

level_db

float pulp::signal::drum::VelocityResponse::level_db = 18.0f

Attenuation at velocity 0, in decibels below a full-velocity hit.

noise_balance

float pulp::signal::drum::VelocityResponse::noise_balance = 0.0f

Shift toward the noise layer at full velocity, 0 to 1.

A harder strike puts proportionally more energy into the transient than into the body.

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The documentation for this struct was generated from the following file:

• /home/runner/work/pulp/pulp/core/signal/include/pulp/signal/drum/velocity.hpp