External FX Not Working

Hello.

I want to process a vocal with outboard equipment, and I’m totally perplexed with the results I’m getting. It’s probably simple human error, but I’m having trouble finding the error. Please help if you can.

Project facts:

  1. I am working with a single vocal track.
  2. In “Routing”, the input is set to “No Bus” and the output is set to “Stereo Out”.
  3. In “Audio Connections—>External FX”, I have set up the effect I would like to use. “Send Bus 1” is set to Line Out 2, “Return Bus 1” is set to MIC/LINE 1, and the appropriate connections are made on the rear panels of both my audio interface (UA Apollo x8) and the outboard equipment (Avalon 737).
  4. The external effect is inserted on the vocal track.
  5. Signal is clearly getting to the Avalon. The VU meter shows signal. Part of the problem here is that it is not only the vocal going to the Avalon and I cannot figure out why. As far as I can see, nothing else is routed to Line Out 2.
  6. I can hear the result when I turn up the output of the Avalon, even though the channel it’s going into on the interface is muted. The sound is bad, and if I turn it up, I get a nasty squealing feedback.

Any suggestions? I’d love to compress and EQ this vocal with the Avalon.

I don’t think Cubase 13 allow you to use an input or output in Audio Connections twice (this changes in Cubase 14). This leads me to think your issue may be outside of Cubase. Have you checked the setup of you Apollo?

I don’t think I’m using any outputs twice. When I enable the output in Audio Connections–>External FX, a popup appears saying “The selected device port is already used. Selecting the port for this bus will replace any previous connection.”

Did you mean something else?

No, that is what I meant. In Cubase 13 (as well as previous versions) an audio output can only be used once. So if you wish to use “Output #5” for your External FX, it is not possible to use it anywhere else.
So if your External FX is set up with the correct input and output, the issue is more likely to lie somewhere outside of Cubase. This is why I suggested you look into the setup of your Apollo.

Do you use control room…make sure Line Out 2 isn’t in use there if you do.

I don’t know how X8 treats monitor outs compared to line outs…maybe worth trying a higher numbered output just in case 1/2 and Monitor L/R are mirrored by default.

Yes, I use control room. But the connections in CR are disrupted when I connect External FX, same as any other output. But I followed your suggestion and tried Line Out 8. The External FX insert now works as expected. I’m happy but also perplexed. I’ll have to pinpoint the problem within the UA software settings. Thanks for the suggestion!