I record by choosing a stereo track in audacity and using my Motu AudioExpress with the mic in input 1 and my guitar in input 2. I’ll do a song both playing and singing because I like the feel and sound as if I’m playing live… And I find it easier with timing to do that as opposed to singing over a guitar track. I know in studio they typically record both individually and then mix them into one. The vocals will go to Left and the guitar will go to Right speakers on playback. It has great sound but to me that’s not really stereo. Is there a way to have both the vocals and guitar play back in both left and right speakers with out recording each separately? Thanks!
FYI - A true-mono file will play from both speakers. Or, you can have a “dual mono” file with identical left & right channels.
There’s more than one way to do that but probably the easiest way to do it is to click the little drop-down arrow to the left of the waveform and select Split Stereo To Mono. When you export you’ll get a true-mono file with the audio from both tracks.
There are also ways of panning each track nearly to the center which might give you some “stereo feel” without sounding too weird.
It has great sound but to me that’s not really stereo.
I’d call it stereo but it’s not realistic stereo… 
There are some early stereo Beatles songs with all of the vocals on one side, drums on the other, and nothing in the “center”.
\
In a “perfect world”, I’d record your voice & guitar separately and double-track the guitar. (Play and record the guitar twice). Then put your vocal in the center (identical in both channels) with one guitar on the left and the other on the right. (Perhaps not hard-panned, but mostly to the left & right).
You can actually almost do that if you can play the guitar with more than once with “close” timing… You can play & sing at the same time without a mic on the guitar, or by killing/reducing the guitar track after recording… You’ll get some leakage, but that’s OK… It’s probably good… Then record the guitar two more times (so you’d actually be triple-tracking the guitar).
It gets stickier than that because you can’t have a vocal microphone in the same room with an acoustic guitar. There will always be cross leakage, and once you have a cross like that, your production options drop way down.
So ideally you would send your electric guitar to be recorded without your hearing it, or only hearing it with headphones. Record the voice naturally. Yes, it is awkward.
This is where overdubbing naturally pops up. create a click track, play that back into your headphones while you play and then play both back while you sing or play more. Properly set up, Audacity will give you clean individual tracks for every layer. Special effect your brains out, or play more.
Nobody said you can’t record a composite and then sing and play to the composite if that’s more comfortable. The backing track can be anything.
These two were doing this on physical tape There’s a picture of the machines in that clip. There’s only two people in that recording. Les Paul is the father of overdubbing.
https://www.youtube.com/watch?v=NkGf1GHAxhE
See
I’m surprised nobody mentioned echo and reverb. That’s the classic way of turning flat mono into [[[[[[Dimentional Stereo]]]]]]]. If you do it just right, you can be playing Disney Hall instead of in your garage.
I’ve never converted a performance, but I understand you split the mono into two monos, assign them Left and Right and apply different reverb to each. Others may post. That’s what a venue would be doing in real life. Do it in threes so you can have good control of the center channel. The main performer is almost always in the middle.
I have a friend about two miles away that has a “live” living room with a high ceiling. It’s amazing. I think they have no idea what they have.
“How about I buy the pizza and you leave me alone in there for a couple of hours with a microphone.”
Koz
Koz & Doug - really appreciate all the input! You gave me a lot to think about and work on and this is exactly what I was looking for.
Thanks again!