Stereo vs two mono tracks

[brandon]

I appreciate this topic has been covered before but I cannot quite grasp the difference in the above. 

If we think along the lines that a stereo audio track is essentially 2 wav forms 'wrapped' within a single wav file. As far as I can see there is nothing in those wav forms that makes them any different to two mono tracks of an identical recording . And if we split a stereo track into 2 mono tracks that is what we would have. 

So I hit a brick wall when I learn that a stereo track will sound different to 2 mono tracks (that are panned accordingly left and right) as I cannot see any physical way that this can be possible. There has been no magic being performed in the recording of a stereo file that makes it different. It is the same 2 dimensional wav form.  Please note I have discounted the fact that 2 different mics will provide two different recordings (and therefore that adds to the stereo effect) as that is irrelevant here.

Any advice that would help with my thought processes would be much appreciated.

Many thanks

 

[Glenn Stanton]

the main difference - dual mono is two files, stereo is typically 1 file. multiple channels (like surround) may be one or more files (depending on if they're encoded or raw really). if you have a single panning control (like the console track) then stereo files will tend to keep their channel relationship. if you have two tracks (dual mono) then your panning could change the relationship (assuming they're not strictly mono - same material in each).

[brandon]

2 hours ago, Glenn Stanton said:

the main difference - dual mono is two files, stereo is typically 1 file. multiple channels (like surround) may be one or more files (depending on if they're encoded or raw really). if you have a single panning control (like the console track) then stereo files will tend to keep their channel relationship. if you have two tracks (dual mono) then your panning could change the relationship (assuming they're not strictly mono - same material in each).

Thanks. Do you think that two mono tracks could, if a good panning technique was used, ever sound like a stereo track Glenn?

[Glenn Stanton]

sure. in dual mono  - meaning 2 mono tracks, should sound like a single stereo file when panned center (meaning levels between them are as recorded). and if you have separate pan controls (e.g. protools) on the stereo file (remembering the stereo file is really two separate mono channels in a single file), you have the same concerns about the relationship between the channels as separate mono tracks each having a single pan control.

you could easily test this: set up two mics in an XY pattern, as separate channels in your IO unit, record as stereo on one track and record each channel as mono on two tracks. you can do this at the same time.

try side by side, same thing except the spill in the mics should be more obvious depending on the distance and source, and then try another. in all cases you should see/hear that both the dual mono and the single stereo are the same. here's a reference for the mic'ing: https://blog.samson.co/blog/2019/08/4-stereo-microphone-techniques-with-audio-samples/ and of course: https://www.dummies.com/?s=+Stereo+Microphone+Techniques

[brandon]

Thanks again and that's a good example. Am glad someone agrees with me as I would have spent lots f unnecessary time pondering over whether to record stereo or mono. I have read a great deal about stereo recordings being more wider spatially than mono recordings are and I couldn't fathom out why - and I do believe there is no (and cannot be no) difference.

[Glenn Stanton]

so, don't confuse the file content with the file representation - a mono recording is "not wide". a stereo recording, if its a single mono source is "not wide", its just "big mono".

there are techniques for "widening" mono tracks. and even more for "widening" proper stereo content. sometimes, using mid-side recording (effectively 3 tracks) is excellent for some purposes because you can change the relative width of the content from stereo to mono with excellent mono integrity retention. there is also lot's of discussion on LCR "stereo" (left-center-right) panning and the various degrees within a stereo image.