Linux Studio Plugins Project

# Ring Modulated Sidechain Mono

Detailed: LSP Ring Modulated Sidechain Mono (RMSC1M)

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

Categories: Dynamics

Developer: Vladimir Sadovnikov

Description:

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

The simplified process can be described by following steps:

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

Such algorithm allows to mix two signals with 0 dBFS peak values without going out of 0 dBFS range.

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.
- Pause - pauses any updates of the time graph.
- Clear - clears all graphs.
- 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.
- 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.

- 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.
- SC - enables drawing of sidechain input graph and corresponding level meter.
- Gain - enables drawing of gain amplification line and corresponding amplification meter.
- In - enables drawing of input signal graph and corresponding level meter.
- Out - enables drawing of output signal graph and corresponding level meter.

Processor section:

- 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.

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.

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.