- Dynamic Processors – such as compressors – in general use the the original - input signal for analysis and operate on the same signal. - Side-chaining uses the signal level of another input to control - the compression level of the original signal. + Dynamic Processors—such as compressors—in general use the the original input signal for analysis and operate on + the same signal. Side-chaining uses the signal level of another input to control the compression level of the + original signal.
+- Effect Processors which have a side-chain input (sometimes also called key input) - have an additional input pin to receive a signal from an external input. - In Ardour that extra input can be connected in the plugin's Pin Configuration - dialog: the signal from one track can be tapped off and used as an input to a - plugin on a different track. This dialog is - accessed via the plugin's context-menu > Pin Connections…. + Effect Processors which have a side-chain input (sometimes also called key input) have an additional input pin to + receive a signal from an external input. In Ardour that extra input can be connected in the plugin's Pin + Configuration dialog: the signal from one track can be tapped off and used as an input to a plugin on a different + track. This dialog is accessed via the plugin's context-menu > Pin Connections….
+- In case a plugin has a dedicated sidechain input, Ardour automatically - creates a port for the input. This is a normal I/O port which can be fed by any - external signal. - The Pin Configuration dialog is not limited to - processors with a dedicated sidechain input, it also allows to manually create - (or remove) a sidechain input port and provides for flexible connection of the - signal to plugin pins. + In case a plugin has a dedicated sidechain input, Ardour automatically creates a port for the input. This is a normal I/O + port which can be fed by any external signal. The Pin Configuration dialog is not limited to + processors with a dedicated sidechain input, it also allows to manually create (or remove) a sidechain input port and + provides for flexible connection of the signal to plugin pins.
+- The operational flow in the Ardour GUI starts at the processor which is to receive - the signal: a sidechain source is selected, and Ardour creates a dedicated send-processor in the - source processor box, the level of which can be adjusted either in the Pin Configuration window - or directly on the source's send. + The operational flow in the Ardour GUI starts at the processor which is to receive the signal: a sidechain source is + selected, and Ardour creates a dedicated send-processor in the source processor box, the level of which can be adjusted + either in the Pin Configuration window or directly on the source's send.
- One example is the use of a bassdrum track to trigger - the compression on a bass track. The sidechain compressor (a-Compressor) will be placed on - the bass track, and will need to receive the signal from the bassdrum track as - a way to trigger the compression. + One example is the use of a bass drum track to trigger the compression on a bass track. The sidechain compressor + (a-Compressor) will be placed on the bass track, and will need to receive the signal from the bass drum track as a way to + trigger the compression.
- Here, on the bass track, an a-Compressor has been added, and the - Drum track has been set as the sidechain source. The mixer reflects this - by showing an SC-send processor in the drum track, very similar to a send - The bass track also shows an arrow as one of the a-compressor input. + Here, on the bass track, an a-Compressor has been added, and the Drum track has been set as the sidechain source. + The mixer reflects this by showing an SC-send processor in the drum track, very similar to a + send. The bass track also shows an arrow as one of the a-compressor input.
+- As a result, in the editor, each peak in the kick drum track triggers the compression on the bass track - and the resulting track shows the compression kicking in on each kick drum peak, hence - reducing the gain. The compression is applied to the bass, but only based on the level of the drum track. + As a result, in the editor, each peak in the kick drum track triggers the compression on the bass track and the resulting + track shows the compression kicking in on each kick drum peak, hence reducing the gain. The compression is applied to the + bass, but only based on the level of the drum track.
+- This is commonly used for ducking effect, when e.g. a radio speaker's voice triggers the - compression on the audio playing. + This is commonly used for ducking effect, when e.g. a radio speaker's voice triggers the compression on the audio + playing.
- Ardour allows the sidechain sources to be either audio or MIDI tracks/busses. This is - particularly useful when a MIDI signal is used to control an audio effect, like a - vocoder or an auto-tuner, like fat1, - the LV2 port of Fons Adriaensen's Zita AT1 - by Robin Gareus: + Ardour allows the sidechain sources to be either audio or MIDI tracks/busses. This is particularly useful when a MIDI signal + is used to control an audio effect, like a vocoder or an auto-tuner, like fat1, + the LV2 port of Fons Adriaensen's Zita + AT1 by Robin Gareus:
- Here, the MIDI track is inputed to the plugin's MIDI IN pin through a sidechain, - indicating to the plugin what note should the source audio be corrected to. + Here, the MIDI track is inputted to the plugin's MIDI IN pin through a sidechain, indicating to the plugin what note the source audio should be corrected to.
- Notice that in the example above, the output of the "Vocals" track is connected - to the input of the "Corrected" track. We could have chosen to insert the "Vocals" track - content as an audio sidechain too, totally disconnecting the input from the plugin, and - connecting the plugin's input pin to the audio sidechain port. + Notice that in the example above, the output of the "Vocals" track is connected to the input of the "Corrected" track. We + could have chosen to insert the "Vocals" track content as an audio sidechain too, totally disconnecting the input from the + plugin, and connecting the plugin's input pin to the audio sidechain port.
- Sometimes, the effects of a sidechain signal on a plugin can be enhanced by - pre-processing the signal. + Sometimes, the effects of a sidechain signal on a plugin can be enhanced by pre-processing the signal.
+- In the first example above, if the entire drum part is on one track, - then compressing with this signal as a sidechain will result in every peak triggering the compression, - be them bass drum kicks or snare, cymbals, etc. + In the first example above, if the entire drum part is on one track, then compressing with this signal as a sidechain will + result in every peak triggering the compression, be they bass drum kicks or snare, cymbals, etc.
+- In this case, adding an EQ to the drum track with a low pass filter would filter out the peaks - created by the high pitched instruments of the drum kit, and allow for a better triggering, though to - avoid damaging the original drum track, a send to an intermediary track would be better suited - to place the EQ on. This track won't be connected to the Master, as its content is of no musical - interest except for it's use as a trigger, allowing for some extreme EQ. + In this case, adding an EQ to the drum track with a low pass filter would filter out the peaks created by the high pitched + instruments of the drum kit, and allow for a better triggering, though to avoid damaging the original drum track, a send to + an intermediary track would be better suited to place the EQ on. This track won't be connected to the Master, as its content + is of no musical interest except for its use as a trigger, allowing for some extreme EQ.