This version (02 Jan 2023 11:03) was approved by Jagan M.

Noise Gate


The NoiseGate block is used to control the volume of an audio signal. Computes the RMS Level of an Incoming Audio Signal and Reduces the Noise which is Below a User-Defined Threshold by Setting the Gain as 0

Targets Supported

Name ADSP-214xx ADSP-215xx/SC5xx ADAU145x/146x
NoiseGate Block Block Schematic



Input0AudioInput channel0


Output0AudioOutput channel0

Configurable Parameters

GUI Parameter NameDefault ValueRangeFunction Description
RMSTC 5 ms 0 to 10000 ms Controls the rate of the RMS-approximation calculation used to track the input level.
Decay 5 ms 0 to 10000 msControls the rate at which the signal compression ratio will subside after the input signal level has dropped below the threshold. Larger values result in longer decays, with 23 never recovering to the original gain
Hold 0 ms 0 to 2000 ms Controls the time to maintain it's current output gain when the input level changes
Threshold1 dB -24 to +24 dBSets the threshold point. If the input signal's approximated RMS level falls below the threshold point, Noise Gate attenuates the signals below the threshold by applying gain as 0.This threshold level does not need to be an integer; its resolution can be set in steps of less than 0.01 dB.
NumChannels115Number of input and output channels. Change in this value requires re-compilation

DSP Parameters

Parameter NameDescriptionADSP-214xx/SC5xx/215xx ADAU145x/146x
RMSTCTime constant for RMS calculationFloat 8.24 format
DecayDecay valueFloat 8.24 format
Hold Time to resopond for input level falls below threshold levelFloat 8.24 format
ThresholdthresholdFloat 8.24 format

DSP Parameter Computation

Decay = 1/P^(1000/(Decay * FS))
Hold = FS * HOld/1000
Where P is 1/9 and FS is the sampling rate

Where FS is the sampling rate

resources/tools-software/sigmastudio/toolbox/dynamicsprocessors/noisegate.txt · Last modified: 25 Apr 2022 09:35 by Jagan M