Multiband Ring Modulated Sidechain Stereo

Detailed: LSP Multiband Ring Modulated Sidechain Stereo (MBRMSC1S)

Formats: CLAP, JACK, LADSPA, LV2, VST2, VST3

Categories: Dynamics

Developer: Vladimir Sadovnikov

Description:

This plugins performs multiband ring-modulated sidechaing of the audio signal.

The simplified process can be described by following steps:

Split input and sidechain signal into multiple bands.
Process each band independently:

Rectify the sidechain signal. All negative audio samples on sidechain input change their sign and become positive.
Limit the sidechain signal. All audio samples of the sidechain signal that come from previous step are limited by the 0 dBFS threshold.
Modulate the original signal. The original signal is multiplied by rectified and limited sidechain signal.
Subtract from the original signal. The modulated result is subtracted from the original signal.

Mix processed bands together.

As a side effect, because sidechain signal can change rapidly, the original signal can become distorted. To minimize distortion effect, additional smoothing, prediction and reactivity controls were added.

Controls:

Bypass - bypass switch, when turned on (led indicator is shining), the output signal is similar to input signal. That does not mean that the plugin is not working.
Mode - the crossover mode.

Classic - classic operating mode using IIR filters and allpass filters to compensate phase shifts.
Linear Phase - linear phase operating mode using FFT transform (FIR filters) to split signal into multiple bands, introduces additional latency.

Slope - the slope of crossover filters.
Type - The sidechain source type:

Internal - the input signal is taken as a sidechain after pre-mixing stage.
External - the sidechain input signal is taken as a sidechain after pre-mixing stage.
Link - the shared memory link is used as a sidechain input signal after pre-mixing-stage.

Source - The sidechain source type for both left and right channels:

Left/Right the left and right channels are processed using the left and right channels of sidechain respectively.
Right/Left the left and right channels are processed using the right and left channels of sidechain respectively.
Left both the left and right channels are processed using only the left channel of sidechain.
Right both the left and right channels are processed using only the right channel of sidechain.
Mid/Side the left and right channels are processed using the middle and side signal repesentation of sidechain respectively.
Side/Mid the left and right channels are processed using the side and middle signal repesentation of sidechain respectively.
Mid both the left and right channels are processed using only the middle signal repesentation of sidechain respectively.
Side both the left and right channels are processed using only the side signal repesentation of sidechain respectively.
Min both the left and right channels are processed using the minimum signal between left and right channels of sidechain.
Max both the left and right channels are processed using the maximum signal between left and right channels of sidechain.

Pre-mix - shows pre-mix control overlay.
Mix - shows the Dry/Wet control overlay.
Link - the name of the shared memory link to pass sidechain signal.
Zoom - zoom fader, allows to adjust zoom on the frequency chart.

Band-processing controls:

Band number button - enables additional split filter in the crossover and associated band with it.
Range - allows to set the frequency range for the band.
On - enables the signal processing for the selected band.
Solo - turns selected band into solo mode.
Mute - mutes the selected band.
Lookahead - allows to add some small delay to the signal and force sidechain to reduce the input signal earlier than actual peak happens.
Ducking - allows to add some small post-delay to the sidechain signal to force slower shutdown of the sidechain signal.
Hold - the time period the sidechain envelope holds it's maximum value before starting the release.
Release - the release time of the sidechain.
Amount - the additional pre-amplification of the sidechain signal before the limiting stage.
Stereo link - the knob that allows to set how the gain reduction of the left channel affects the gain reduction of the right channel and vice verse.

Signal section:

Input button - allows to pass the processed input signal tho the output of plugin.
Input knob - the loudness of the processed input signal.
Sidechain button - allows to pass the unprocessed sidechain signal tho the output of plugin.
Sidechain knob - the loudness of the unprocessed sidechain signal.
Output - the overall loudness of output signal.
Active - enables side-chaining effect. May be useful for A/B testing the signal with sidechain effect and without it.
Invert - enables inverse function: in this mode the plugin works like a ring modulator instead of rin-modulated sidechain.

'Analysis' section:

FFT In - enables FFT curve graph of input signal on the spectrum graph.
FFT SC - enables FFT curve graph of sidechain signal on the spectrum graph.
FFT Out - enables FFT curve graph of output signal on the spectrum graph.
Reactivity - the reactivity (smoothness) of the spectral analysis.
Shift - allows to adjust the overall gain of the analysis.

Pre-mix control overlay:

In -> SC - the amount of signal from input channel added to the Sidechain.
In -> Link - the amount of signal from input channel added to the shared memory link.
SC -> In - the amount of signal from sidechain input channel added to the input channel.
SC -> Link - the amount of signal from sidechain input channel added to the shared memory link.
Link -> In - the amount of signal from shared memory link added to the input channel.
Link -> SC - the amount of signal from shared memory link added to the sidechain channel.

Dry/Wet mix control overlay:

Mix Dry - the amount of dry (unprocessed) signal.
Mix Wet - the amount of wet (processed) signal.
Mix Dry/Wet - the knob that controls this balance between mixed dry and wet signal (see Mix Dry and Mix Wet) and the dry (unprocessed) signal.