Title says all.
A stereo track has two audio channels.
A mono track has only one.
If that’s not what you meant, then you will need to be clearer in your question.
There are other variations. If you have two blue waves that are identical, you can have Two-Track Mono. Watch if the bouncing sound meter always bounces exactly the same way for both tracks. Real stereo bounces differently.
There is an odder variation where the two blue waves are a different volume but they have the same graphic pattern. That’s much harder to discover, but a home recording can have that if there is a good, single microphone, but a bad computer adapter. That’s a damaged mono recording.
There is a computer adapter which can connect a single microphone to a computer such that it produces two blue waves, but they oppose each other. I call that the “Devil’s Adapter” because it can produce a show that will only play on some computers or music players, and vanish on others.
But the show is still mono.
In none of these cases do have have “direction.” The violins on the left and brass on the right (for example). That’s real stereo.
Which variation do you have, and what prompted the question?
Koz
Is it possible that a monophonic sound be mixed by Audacity into two channels and as such lead me to believe that it’s a stereo track?
Can I compare the two channels in Audacity? I believe if the result says they’re identical then the original sound has to be mono correct?
The Vocal Remover effect subtracts left from right to remove “center channel” vocals. If the channels are digitally-identical you’ll get pure silence. (Use the “simple - full spectrum” option.)
If you recorded in stereo from a mono analog source there will be a slight difference in left & right so some signal will remain and the analog noise (random & different in both channels) will remain.
(Audio CDs are always 2-channels so if you rip a mono CD, you’ll get 2 identical channels.)
Is it possible that a monophonic sound be mixed by Audacity into two channels and as such lead me to believe that it’s a stereo track?
Sorta. I know you’re searching for the one-button solution, but there may not be one. You can start with a single blue wave mono track, duplicate it so now you have two identical blue waves. Select one of them and screw it up. Select the top wave menus and Make Stereo Track.
It’s “stereo” because the Left and Right don’t match. Some older classic mono recordings are processed so that they “seem” to be stereo. “Lead guitar on the left…” through electronic sound tricks. You can start fights about where they really are or not. That can come down to whether or not you’re enjoying them and skip the labels.
I believe if the result says they’re identical then the original sound has to be mono correct?
One partial solution is invert and cancel. Select the track > drop-down menus on the left > Split Stereo Track. Select one of the splits and Effect > Invert. Menus on the left > Make Stereo Track. Select the track > Tracks > Mix > Mix Stereo down to Mono.
If the original was two-track mono, you should be left with a straight line. No blue wave. The two original tracks will cancel to a flat line.
But that only works if the original was a simple two-track mono. If it had any tricks applied, this test fails.
We can guess at it. Drag-select some of the sound (not silence), File > Export > Export as WAV (Microsoft) and post it on the forum.
Also see:
https://forum.audacityteam.org/t/how-to-post-an-audio-sample/29851/1
Please also note we don’t do surveillance, law enforcement or conflict resolution. This is starting to sound a lot like conflict resolution, right?
Koz
If you split stereo to mono & invert one channel the result will be silence if they are identical.
Alternatively, (free) stereo visualizer plug-ins are available which work in Audacity in windows …
e.g. Mid-Side Encoder-Decoder Plugin [VST, AU, AAX] - MSED - Voxengo
https://www.izotope.com/en/products/ozone-imager.html
HoRNet StereoView, free stereo goniometer and correlation meter plugin
(NB: Currently only 32-bit , VST, (not VST3), plugins work in Audacity in Windows).
The “Analyze” option in the “Vocal Reduction and Isolation” effect gives a measurement of the “correlation” (similarity) of the two channels. See: Vocal Reduction and Isolation - Audacity Manual
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Hi Steve, I had to sign up for this, because your answer is, so far, the best, when it comes to identifying, if a record track is stereo or mono.
THANK YOU!