Mono Track with Stereo FX


I think I’m coming back to Cubase. A 3 year detour to Logic (and while it has many nice features) it seems Cubase caught up with most of them, while having much better performance and efficiency. However there are still a few features lacking!

One thing I do on a regular basis in Logic is record a mono Vintage Synth track into Cubase via Audio. Then I would like to apply FX to it. Usually I use my analog external hardware for this…but sometimes it is also a plugin.

For external hardware:

It seems that the Mono to Stereo External FX plugin does not work properly on a Mono track? It loads up but it seems to sum both return channels to mono. (Which makes sense because it is a mono track) But it there a way it can understand this and automatically make the mono track a Stereo Track?

Or how is this achieved?

My external FX are not always just reverbs. An analog chorus I would love to quickly and easily route the Mono Audio track (via the external FX plugin) and it be 100% wet, so no need for a bus etc etc. Or is that the only way to achieve this?


Route the output of the mono Instrument to the Stereo Group Channel, and apply the Stere FX on the Stereo Group Channel.

Alternatively create a mono input and route this to a stereo track. This will show as a mono track (ie one single audio file), but will be able to process stereo efx. Obviously this track will use slightly more cpu resources. I very rarely use a mono track these days. I do all my guitars in this manner so that they can have individual stereo delays and other processing.

You mean record into a stereo track?

The thing is…I typically will record all my mono synths (well mono). Because alot of the times I don’t process them straight to a stereo device, rather I route them to my 1176 hardware or other hardware compressor/filters via the external FX plugin. Those are mono out/mono. So what would happen on a stereo track if I use a mono External FX plugin? Probably not good right?

I guess my only option then is your first one.
Since a majority of my studio is Hardware I am going to have alot of Stereo Group Channels just to process my mono audio tracks and make a mix(if it involves mono to stereo). I’ve been gone since Cubase 6, but I’m surprised this hasn’t come up and been implemented like it is done in Logic.

Place mono files on mono tracks for mono processing.

Place mono files on stereo tracks for stereo processing.

You may also take a look at the insert routing editor for additional routing options.

I tried various things during lunch and it actually seems that Cubase cannot do what I was expecting it to be able to do. (mono to stereo)

This applies for all of the workflows suggested above.

Basically the only way I can get an Mono-to-Stereo External FX to work correctly from what I see is by making it a Stereo FX. Therefore I essentially waste an output channel of my interface. ie I have to assign Out 3 and 4 to External FX and coming back on In 3 and In 4. But I’d rather not use up Out 4 (only need Out 3) is I’m only sending a mono signal.

If anyone knows otherwise please let me know, but this seems to be the behavior for External FX channels. Surprised it cannot do this.

I think this approach applies for Plugins, yes…but it does not seem to work for External FX with Mono Send and Stereo Return. Try it and you will see.

An external FX is in fact a special case of a plug-in. Both Send and Return should be configured as stereo. By placing a mono file on a stereo track one gets a stereo signal that is composed of two identical mono signals. That is to say, there are two channels in action and they both have to be processed simultaneously.

Have you tried this scenario:

Mono file on a stereo track > Ext. FX Out 3 (enabled) + Ext. FX Out 4 (disabled) > DA for Out 3 > Y cable > Ext. Processor L + R > AD for Ins 3 + 4.

I can try that…but no need for a Y Cable.
Many vintage hardware FX Boxes (and even some current Guitar Pedals for that matter) have 1 input and 2 outputs.

For example take a look at the Yamaha SPX90. It has 1 mono input, but 2 stereo outputs.
I have a few pieces like that in my studio, this is why I am asking the question.

I never record to a mono track as I see no reason for it. Some more discussion here…

Regards. :sunglasses:

If I was all ‘in the box’ I would do the same.
However I am not.