@ Gear lover - to answer your question about the stereo track i must honestly say i cannot tell you a referenced answer. Why when you record something in mono and pan it hard left can you get the impression its panned further left when adding a stereo imager/enhancer? I mean isnt hard left supposed to be at 90 degrees left? I would suppose its to do with the sonics of the audio and how it is being replecated until it gets to your ear. For example (this is theoretical) a mono channel plays the same audio at the same signal strength out of both channels at the same time - when you pan it adjusts the amount of signal strength accordingly in a linear fashion. In a stereo channel you hear 2 different signals from 2 different speakers LR - in effect 2 mono channels panned hard left and hard right. When adjusting the balance between left and right you are actually turning one channel up and one down. So i would suppose that the harmonics in each individual track and heard differently as the volume is altered. sounds at 1Khz need to be played less loudly than sounds at 100Hz to be heard so we could be hearing different sonic frequencies of one of the tracks which stand out at lower volumes (panned left we hear higher freqs of right but not lower). After adding reverb etc and the stereo imager then you have sounds bouncing all over which complement and add harmonics to your signal.
Make sure your happy with your recording - eq out the bits your not happy with - you can find these by using a small q on an eq and boosting up to 10db then sweep your freq range - you will usually find them in simlar ranges - look at anything below 1k that might make the vox muddy or boxy - then look above - pay attention at 1khz-3khz. maybe add some sparkle at anything over 8-10 khz - be carefull of sibulance.
Compression - use it - dont be afraid to experiment - some vox need little - some need more, you can even go as far as harsh limiting on rap vox - sometimes squashing it to f*** can make it sound fuller and warmer.
you can do either of the 2 ways you suggested to thicken the track. Techniques i have used are
3 different recordings - 1 flat mic - centre, 1 takes with mics which add presence and warmth - u87
, solid tube
maybe. If you dont have that try recording using different techniques - rec one take 2 inch from mic - one 4 inch - try speaking lower on one take etc then eq them to fit nicely.
Pan same vox hard left/hard right and one center. Make centre the cleanest sounding vox and loudest - try different processors on other 2 like cutting hi freqs a little to make seem a little warmer. You can even put a sample delay on them so they act like a chorus effect but be careful of phasing.
use an exciter to help bring the twinkle out which will help it seem clear and alive even when not as loud in the mix - be careful dont overdue it or it will sound terrible.
I will sometimes send them via a chours but my best trick has been to send a channel through a vocoder and play the vocoder very quitetly in the background using a warm mildly destorted sound. Sat deep in the vox you can hardly hear it but it thickens the vox quite alot.
Use a saturation plugin - helps to add warmth and sit vox better in mix
Add reverb via send - 3 in fact, gate reverb, plate reverb and short reverb drum booths seem to work well on rap - remember to eq out the unwanted lower freqs.
finally eq again - but this time considering more the balance between the vox and the instru - make sure that you eq both the vox and the instru to complement each other - this can mean with tight cues and seaminly rediculous eqing - there are no rules to what sounds good.
another thing which helps alot is having an eq, a compressor/limiter, saturation plugin and maybe an imager on your master channel. these will help also get the track as you will be effecting the track as a whole when altering these plugins.
I hope this helps and boy did it take me a while to type. Let me know what you think.
before anyone starts slating me your free to correct me and ill be happy for the info - i used to think there were rules in music and feel bad when i see people telling others 'you dont know what your doing etc'. the more people i meet in music and the more i learn, the more i realise there are no rules - just what sounds good!