Pro Compressor side chain bug

[Reckless Erik]

Can anyone confirm if this is normal behaviour or a known bug. Procedure is as follows;

1. Place Pro-compressor on a track/aux insert. Label as track A
2. Create a side chain bus for the compressor side chain input.
3. Set compressor to ext side chain trigger.
4. Send another track/aux (Track B) to the side chain bus to trigger the compressor.

Observed and desired behaviour;

When compressor detects signal from Track B in side chain the compressor activates and works normally. When the send on the trigger Track B is muted no compression takes place and Track A is unaffected.

Observed and UNDESIRED behaviour;

When the send on the trigger source, Track B, is made INACTIVE the compressor behaves as if there is no external side chain and compresses the signal on Track A regardless.

[clausiii]

i think when the send is inactive then the key input is also interpreted as not present by the plugin, so the compressor works as it should. Did you try it with a different one?

[Reckless Erik]

A different plugin?

[clausiii]

Yes, any other comp with SC will do, the stock compressor/limiter for example

[yoerik roevens]

Originally Posted by clausiii

i think when the send is inactive then the key input is also interpreted as not present by the plugin, so the compressor works as it should. Did you try it with a different one?

I don't believe that would make much sense. After all, the compressor side chain gets its input from a bus, not from a track. So making the track inactive shouldn't deactivate the bus. What happens if you send 2 tracks to the side chain bus? I.e. add an empty track C, send it to the SC bus as well. Then make B inactive while keeping C active.

[Stig Eliassen]

Originally Posted by yoerik roevens

I don't believe that would make much sense. After all, the compressor side chain gets its input from a bus, not from a track. So making the track inactive shouldn't deactivate the bus. What happens if you send 2 tracks to the side chain bus? I.e. add an empty track C, send it to the SC bus as well. Then make B inactive while keeping C active.

Can't say if this is intended behavior, but it makes sense to me.

SC triggers a compressor based on input signal, and deactivating a single send feeding that SC would be the same as "pulling the plug", atleast in my mind.

If you send a second empty track to the same ACTIVE bus, the compressor will not compress.

[Reckless Erik]

Just to clear things up a bit. When the send on the trigger track is deactivated the problems occur. If you create an empty track below with an active send it makes no difference.Screen Shot 2017-05-12 at 12.02.28.jpg

[Reckless Erik]

This seems to happen irrespective of plugin type. If I mute the send then the VCA in the compressor/gate is not active and signal flows through it un-affected. Desired. But if I de-activate the send the VCA is triggered by the input signal to the plugin even though the trigger source is still selected to external.

[Stig Eliassen]

Originally Posted by Reckless Erik

Just to clear things up a bit. When the send on the trigger track is deactivated the problems occur. If you create an empty track below with an active send it makes no difference.Attachment 8494

Does this happen with the Avid Pro compressor as well? If so, that is not the case here.

[yoerik roevens]

Originally Posted by Stig Eliassen

Can't say if this is intended behavior, but it makes sense to me.

SC triggers a compressor based on input signal, and deactivating a single send feeding that SC would be the same as "pulling the plug", atleast in my mind.

If you send a second empty track to the same ACTIVE bus, the compressor will not compress.

Exactly, so it seems busses get de-activated when they have no input signal assigned to them. Makes sense, bu the pro compressor shouldn`t compress when there`s no active signal routed to it's SC input indeed.

So the OP is absolutely right. This behavior is incorrect.