Can anyone point me to a schematic of exactly how BB King's guiar is modded? A cursory Google didn't yield anything for me.
Also, can anyone tell me exactly what people are referring to by "that old out phase B.B. Live at The Regal tone"? I have Live At The Regal and can't really decide what this is but I'm probably listening more to BB's great phrasing and my most favourite licks to really concentrate on the tone!
To recognize an out-of-phase sound I guess you'll need a guitar with this option and then it's still not easy to be sure about it. There are just too many other factors influencing a guitar sound (like amps, effects, equalizers etc.). Usually an out-of-phase sound is hollow ("twangy") and sharp, but there are many guitars sounding similar without being out-of-phase and other guitars that are out-of-phase when you wouldn't tell.
You certainly know Deep Purple's Smoke on the Water and you'll probably remember it as a tune with a full throttle bassy power riff. Well, eehm, that's what I thought too, but when I modded my first guitar with out-of-phase option and started playing that song, I realized that I'd never come so close to the original sound before, although I had a completely different guitar (Ibanez 345 instead of a Strat). Blackmore's Strat is actually out-of-phase on that one, but I couldn't tell which pickups and whether they are in series or in parallel!
AFAIK B.B.King's Lucille has simply one pickup out-of-phase, so with the pickup selector switch in the middle position it's always out-of-phase. But even in this case you still got a lot of options, because a 335 has two volume controls and this allows to mix the signals. If you turn the controls of one of your pickups to 8 you'll realize how the out-of-phase effect slightly disappears as the other pickup starts to prevail. With one volume at 10 and the other on 5 it is almost completely gone.