Stereo track with mono input, all workflows are bad

When setting a stereo track’s input to a mono source, Cubase behaves oddly: it does not apply the pan law to the source when monitoring (including while recording), but does apply the pan law to the source when playing back. This means if the project has a -6 dB pan law, for example, the input to the track will be 6 dB louder when monitoring and recording than when playing back. Cubase has worked this way for several versions.

So the possible workflows/work-arounds for having stereo tracks with mono sources are:

  1. Only use 0 dB pan law
  2. Have a gain pad as the 1st insert that accounts for the pan law gain and only activate it when playing back
  3. Use two channels: a mono audio channel that feeds a stereo FX channel
  4. Try to make the mono input appear as a stereo input, ignore the channel that is unused, waste the disk space, and add a pan plugin to try and do something something… this is getting silly

Am I missing something? How are other people dealing with this? Can we get a fix for this from Steinberg?

Not sure why you are recording mono sources to stereo tracks, just use mono tracks and there is no issue - you can still send them to a stereo fx bus and pan them in the stereo field. Or have I misunderstood?

There are many reasons to want to record a mono source into a stereo track: voice into a stereo doubler, guitar-post-loadbox into stereo IR, snare into a stereo reverb.

I already listed using a separate FX channel as item (3) in my original post. In addition to it being generally less efficient for CPU load, the specific workflow problems with that approach include:

-You can’t freeze the FX channel with the souce track

-Extra tracks that can’t just be hidden in the mixer since record, monitor, pre-filter, etc. must be done on souce and mute, pan, level, etc. must be done on FX channel. Especially problematic if you use something like Mackie MCU where track real estate is precious.

So I’m afraid this doesn’t actually solve the problem without introducing new ones.

Cubase simply applying the pan law when monitoring and recording like is done for playback would solve the problem, though. Reasons why Cubase doesn’t do this continue to elude me.

I generally don’t Monitor using the Track I’m recording to and instead have a dedicated Channel for Monitoring the Inputs. If you used a scheme like this you could adjust for the Pan Law difference with the Pre-Gain (or even the Fader).

A lot of folks do this. A big reason is that Cubase doesn’t let you easily convert a Mono Track into Stereo. Sometimes you might want to put an Insert like a Stereo Delay on a Mono signal. On a Mono Track the Delay will collapse to Mono - where as a Stereo Track will always work. The way around this is to migrate the Mono Audio onto a Stereo Track, or record the Audio onto a Stereo Track to begin with. So rather than fitzing around with both Stereo & Mono Tracks it is simpler to always record to Stereo Tracks for both Mono & Stereo sources.

The problems I have with extra “monitor” channels are (A) ideally you want to monitor as close as possible to what will result in the playback including inserts, since it can very strongly affect performance, especially IRs for loadboxed guitar tube amps. And (B) the cumbersome workflow aspect of muting and unmuting channels to replay what was just recorded, same issue as my workflow/workaround #2 in my original post.

Funny, I’m the opposite. I like a separate Monitor Channel mainly because it lets me listen with effects that I’d never use on playback - for example drenching a monitored vocal in way too much reverb. Totally agree about it affecting performance, but for me that is exactly what I find valuable in the dedicated Channel.

Good luck

I can see how that would work for you. If only Cubase behaved in a sane way, then we could do both.

What happens if you use the Stereo Combined Panner with L & R set hard left and right vs. L & R both set to the center?

Since this pan law application discrepancy happens before any of the stereo track channel processing in the signal path, the track’s panner makes no difference. Indeed, you can observe the discrepancy in level using, for example, Supervision as the first insert.

You can drag a mono part onto a stereo track and it works ok (in Cubase 12 at least) however for monitoring in stereo while recording, the only workaround I can imagine is to use a “Y” cable to record to the left and right inputs simultaneously. Perhaps you could use a guitar pedal that has a stereo output in bypass or a mixer.
Does any DAW handle this the way you want?

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Studio One works the way I would expect. I actually suspect every other DAW does this correctly. It’s really the only sane way. So I’m assuming this is a bug in Cubase. I can’t imagine why anyone would want the behavior Cubase exhibits.

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I have been using Cubase since the Atari days (obviously MIDI only then) and have never encountered the problem to which you refer. I suspect my workflow is considerably different from yours though, hence asking why you would want to record mono inputs to stereo tracks!

Here are steps to reproduce this bug:

  1. Create a new project
  2. Set project pan law to -6 dB
  3. Add a STEREO audio track
  4. Set the input source to the track to a MONO input source
  5. Add Supervision insert to the track
  6. Set Supervision to Level
  7. Arm track for recording, and start recording
  8. Send some test signal to the audio input
  9. Observe the level of the signal in Supervision
  10. Stop recording
  11. Start playback
  12. Observe that the level of the signal in Supervision is 6 dB lower than while recording

Just came to confirm that also exists on my setup if it is indeed a bug. This is incredibly frustrating for those of us who multi-track with a lot of synths/modular gear.