Dark Audacity Question on Mixing - Stereo or Mono

Ok, so I download a wikiloops mix track in .Wav format and open it in Dark Audacity and save the File on my PC( which I record to via audio interface). I then open another file to make my recorded addition. I listen to the original track through headphones with using iPad so I don't get a recording bleed over.

Question: Should I add a mono track or a stereo track as my addition to the recording if I am only adding my voice or a solo instrument?

The downloaded mix is always in stereo. When I export to .wav, Dark Audacity mixes it down, but I am not sure if my voice or instrument is ending up on one channel as a separate channel. Any thoughts?

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I had to look up "Dark Audacity". I'm relearning Audacity after a few years of absence.
What audio interface are you using? Mine allows for monitoring both the original track AND the track I'm recording with either my speakers or headphones.
To your question... It probably doesn't matter whether you record a mono or stereo track, unless you're recording with two mics or signal sources. That would add some depth to your track and give you more mixing flexability.
Cheers,
David

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