out of phase / beyond the stereo field

[Bitfiend]

a friend came by and we got into a discussion about this. i was continually getting spikes beyond the stereo field in a project and he thought it was completely irrelevant if everything was done ITB. He stated it would only be something to worry about if you were actually recording an audio signal and that you almost couldn't truly go out of phase if, as stated, it was all created ITB. he also pointed out chorus, phaser, flange, are all supposed to modulate the signal out of phase as that is there intent.
so is it really not an issue to worry about if everything is ITB start to finish? Which also got me thinking; almost all PA systems are mono so even if a part was truly out a little would it really make an audible distinction in a club or party setting?

[Medway]

You can certainly go out of phase ITB, just take a sound and flip the phase and mix back in and it will disappear as its completely out of phase...

Has nothing to with ITB or OTB.

Yes it is their intent but there are cases where you don't want something out of phase in case it cancels out on a mono system. But for say a mono phaser effect what you hear is mono anyways so thats not a case where it would be an issue.

Or even an eq works by sending a signal out of phase which is what results in the change of tone. Changing phase is a common process the problem is usually from using wide stereo effects that dont convert to mono gracefully.

Just flip over to mono now and then and see if any of your sounds cancel out dramatically. It's mostly a problem where you have a big stereo lead sound with a wide effect, then if you flip to mono it will be much quieter.

If that happened in a club with a mono system then your lead will not be heard so obviously might not make the track sound great overall.