Can you setup an external FX sidechain to feed a compressor?

Hi all,

Not yet a Cubendo user, been thumbing through the manual, forums and various YouTube videos for a while.

I have some noobish questions that haven’t been answered by various YouTubers, but this may just be 4am brain in full effect:

  • Can you setup an external FX sidechain to feed a compressor in a friction-free way? (I would hope so!)
  • What would the optimal way to do this be? Would you setup a dedicated ‘External FX’ just for the sidechain? Or would you make it a part of your compressor ‘External FX’ (e.g. three sends on one ‘External FX’ assuming stereo send-return bus, and a mono sidechain bus on the same ‘External FX’?)
  • Would it be delay-compensated in sync with the stereo send-return of the compressor?
  • Or would the better way to do this simply be to create a sidechain ‘bus’ and not treat it like an ‘External FX’? Or would I create a bus that then feeds an External FX as an Insert?

Sorry if these are silly questions. I couldn’t find anyone talking about this online, so I’m assuming it’s either so simple that I’m overthinking it, or it’s a little obscure.

Would this feature be in the trial for Cubendo to try out? (Only just discovered there’s a seemingly fully featured trial now! Ack.)

Hi there,

you can define your external effect as a, well, “External Effect” in Cubase’s Audio Connections panel.

Then you would create a dummy audio track (or effects track, doesn’t matter) and load that defined External Effect as an insert effect. Note: Cubase will allow you to compensate any delay manually so that your external effect gets in sync with the rest of Cubase.
Set the output of the dummy track to “No bus” if you want to use the signal only for the side chain.

If you setup the side chaining itself you then select that dummy track as the source.

I know your problem. It’s a bit puzzling.
To get around, there are a few ways I can think of but the following must be the easiest if you can afford some CPU time.

  1. make 2 external effects, one for main and another for side-chain, connect only send for side-chain ext efx.
  2. insert the main ext efx to a group (you can also do it on master, but easier if inserted to a group)
  3. insert the sidechain ext efx into another group
  4. do mixing. You can insert any post effects to the main group, after the main external effects. Route this to master, and also can insert master plugins.
  5. insert the same plugin sets as the main group to the sidechain group, route the group to the same destination i.e. master. (<- the side chain ext.efx has no return, so this group don’t make any sound, but important to connect to the same destination for PDC.)

If you insert the same plugins on the side chain group and route to the same destination like above, the amount of the buffer size becomes the same, so the side chain signal will be pre-delayed by the same amount as the main signal. Only inserts after the main ext efx should be copied to the SC group. No need to worry about pre-efx.

This is the easiest, I think.

You can also do this on 2 audio tracks, one for signal and another for just SC. The principle is the same, use the same amount of post plugins on SC bus, and route to the same destination. Also possible to do it on master and output, too.

Another way is to create 1 extenal effect with 1 stereo + 1 mono sends (1 for sc) and a stereo return and use this instance on a quad group. This will be a bit tedious because all the panner of the signal sent to this group will be changed and you have to send to back side for SC.

The problem is, any plugin inserted after the main external effects and the sidechain signal will affect the timing between 2. So you have to match the Cubase’s internal PDC amount. The easiest is above, use the same amount of post plugin and route to the same destination.