Why can't we just use our ears? Put a mono LP on and the sound/image should be coming dead center, right? If's it's one side or the other, you know you need to adjust Azimuth... am I missing something???
Yes, Sonny - I think you
are missing something!

Put a mono record on and, yes, the soundstage should appear to come from the centre ... but only if the following parameters are equal (or compensate for each other in terms of L & R channels):
* output of phono cartridge.
* output of phono stage.
* output of preamp.
* output of power amp.
Otherwise, you have to use your balance control to centre the image.
If all these parameters
are equal (or you've adjusted your balance control to centre the image), I don't think altering
azimuth will change anything. However, I'm not sure about altering bias (in a mono situation).
Regards,
Andy