Convolver

• Effect
• Since 0.2.0
• convolution
• impulse
• room
• cabinet
• ir

Open in TuneToys

Convolver filters a sound through an attached WAV impulse response, for sampled rooms, speaker cabinets and creative textures.

What it does#

The impulse response is loaded and prepared away from the audio callback. The dry input is delayed to align with the processed signal. There is no automatic impulse normalization; adjust the wet gain for the response you attach. The bundled help patches use an original room impulse.

When to use it#

Use it to reproduce a measured space or cabinet. Use Reverb for a synthetic room whose decay and damping you can shape continuously.

Ports#

Parameters#

• asset: asset.

Mix (mix)#

Blend from the dry input, delayed to stay aligned, to the convolved signal.

Predelay (predelay_ms)#

Delay before the convolved signal, to separate a room's reflections from the dry sound.

Gain (gain)#

Level of the convolved signal. Impulse responses vary widely in level; there is no automatic normalisation.

IR start (ir_start)#

Where the impulse response starts, as a share of its length. A change rebuilds the response in the background and crossfades to it.

IR length (ir_length)#

How much of the impulse response is used after IR start, as a share of its whole length; shorter shortens a reverb's tail.

Partition (partition)#

Block size in samples, which is also the latency. Smaller is quicker but costs more processing. Fixed when the Toy is prepared, at the largest value it admits.

Tips#

• Attach a licensed WAV impulse through data.asset and the Toy's asset table.
• Reduce Gain for loud impulses and leave output headroom.
• Trimming the response can shorten its tail; Partition trades latency for processing cost.

See also#

Reverb, Delay, Sampler.

Help patches

Each help patch is an ordinary Toy that teaches one idea. The diagram shows the Patch; the preview shows its Frame. Open it in TuneToys to play and edit it.

1. Put a sound in a room

beginner Teaches: mix, gain, predelay_ms

Short saw notes convolved with a small room's impulse response, with Mix, Gain and Predelay.

Connections as text

• Oscillator audio output connected to Gain audio input
• Control LFO control output connected to Gain @level input
• Gain audio output connected to Convolver audio input
• Convolver audio output connected to Patch outputs audio input

• The room is a recording of how a space answers a click: its impulse response. This one is a 1.2-second small room made by Tune.Toys, attached as a WAV asset.
• Every note is played through that answer, so it sounds as if it were in the room. Mix sets how much room you hear.
• Predelay holds the room back for a moment so the notes stay clear. Gain sets the room's level on its own.

Open in TuneToys

2. Trim the response

intermediate Teaches: partition, ir_start, ir_length

IR start and IR length cut the impulse response down; Partition trades latency for processing.

Connections as text

• Oscillator audio output connected to Gain audio input
• Control LFO control output connected to Gain @level input
• Gain audio output connected to Convolver audio input
• Convolver audio output connected to Patch outputs audio input

• IR length keeps only the first part of the response: at 40 % the room's tail is cut short, like a smaller, drier space.
• IR start skips the direct sound and early reflections, leaving only the diffuse tail. Each change rebuilds the response and crossfades to it.
• Partition is the block size and the latency. It is fixed when the Toy is prepared, so a change here applies the next time it is opened.

Open in TuneToys

Related nodes

• Reverb An eight-line modulated feedback-delay network with room, hall and plate-like tunings.
• Delay Tempo-aware, smoothly retimed echoes with colored, ducked and explicit multichannel feedback.
• Sampler Plays an attached WAV asset as an instrument of up to eight voices in the Toy's tuning, with a playback region, a sustain loop and ADSR.