FluidAmpGate : FluidRTUGen : UGen : AbstractFunction : Object
Extension
ExtensionDescription
Absolute amplitude threshold gate detector on a realtime signal
AmpGate outputs an audio-rate, single-channel signal that is either 0, indicating the gate is closed, or 1, indicating the gate is open. The gate detects an onset (opens) when the internal envelope follower (controlled by rampUp and rampDown) goes above a specified onThreshold (in dB) for at least minLengthAbove samples. The gate will stay open until the envelope follower goes below offThreshold (in dB) for at least minLengthBelow samples, which triggers an offset.
The latency between the input and the output is max(minLengthAbove + lookBack, max(minLengthBelow,lookAhead)).
Read more about FluidAmpGate on the learn platform.
Class Methods
FluidAmpGate.ar(in: 0, rampUp: 10, rampDown: 10, onThreshold: -90, offThreshold: -90, minSliceLength: 1, minSilenceLength: 1, minLengthAbove: 1, minLengthBelow: 1, lookBack: 0, lookAhead: 0, highPassFreq: 85, maxSize: 88200)
Arguments:
| in |
Audio-rate signal to slice |
| rampUp |
The number of samples the envelope follower will take to reach the next value when rising. Constraints
|
| rampDown |
The number of samples the envelope follower will take to reach the next value when falling. Constraints
|
| onThreshold |
The threshold in dB of the envelope follower to trigger an onset: go from 0 (closed) to 1 (open). Constraints
|
| offThreshold |
The threshold in dB of the envelope follower to trigger an offset: go from 1 (open) to 0 (closed). Constraints
|
| minSliceLength |
The minimum length in samples for which the gate will stay open. Changes of states during this period after an onset will be ignored. Constraints
|
| minSilenceLength |
The minimum length in samples for which the gate will stay closed. Changes of states during that period after an offset will be ignored. Constraints
|
| minLengthAbove |
The length in samples that the envelope must be above the threshold to consider it a valid transition to 1. The gate will change to 1 at the first sample when the condition is met. Therefore, this affects the latency (see latency equation in the description). Constraints
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| minLengthBelow |
The length in samples that the envelope must be below the threshold to consider it a valid transition to 0. The gate will change to 0 at the first sample when the condition is met. Therefore, this affects the latency (see latency equation in the description). Constraints
|
| lookBack |
When an onset is detected, the algorithm will look in the recent past (via an internal recorded buffer of this length in samples) for a minimum in the envelope follower to identify as the onset point. This affects the latency of the algorithm (see latency equation in the description). Constraints
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| lookAhead |
When an offset is detected, the algorithm will wait this duration (in samples) to find a minimum in the envelope follower to identify as the offset point. This affects the latency of the algorithm (see latency equation in the description). Constraints
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| highPassFreq |
The frequency of the fourth-order Linkwitz-Riley high-pass filter (https://en.wikipedia.org/wiki/Linkwitz%E2%80%93Riley_filter) applied to the input signal to minimise low frequency intermodulation with very short ramp lengths. A frequency of 0 bypasses the filter. Constraints
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| maxSize |
The size of the buffer to allocate at instantiation time for keeping track of the time-critical conditions ( Constraints
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Inherited class methods
Instance Methods
Inherited instance methods
Examples
Watch the gate
Use for manipulating FX
link::Classes/FluidAmpGate::