I can imagine perfect pitch might even be a handicap if you don’t have good relative musical memory. Music is really about relationships and distances, not any absolute number of cycles per second.
I’d like to hear from a guitarist singer who has PP, about how they transpose a song.
Well, that’s easy. Ultraviolet. What ultraviolet sounds like, I have no idea. 
But I never thought about how someone with perfect pitch perceives pitch. I’ve had fever induced synesthesia (I was tasting shapes that I saw), and it was nothing like that. Thankya.
In what sense? It’s the same as how anyone transposes a song to an different key. The singing is the easy part. The only difference is in playing - remembering to move your fingers to a particular chord when your ear is telling you that a different chord comes next. It is easier to do if you’re not also focusing on singing at the same time. Having the chords written out is handy so less concentration is needed. If it’s a transposition of only a step or two, I can retune my brain enough to think it’s in the correct key. More than that and it gets tricky.
This is why I said that. It sounded like it could be confusing for you to use a capo.
I can’t transpose on the fly, but as a non PP person I don’t think I use any skill that involves PP in my playing. To transpose I use a capo or other chords, but I don’t think about the untransposed music again, maybe ever.
Hmm - I find the barred C-shape to be harder, particularly in the larger frets near the nut.
The pickup is usually hexaphonic (i.e. has six pickups, one for each string). The Line 6 Variax is one such model, allowing simulation of multiple guitar types (Stratocaster, Gibson Les Paul etc). These guitars also allow tuning selection - basically, fret fingering and bend information can be determined by comparing the current string frequency with the open string frequency, and this information is used to synthesize the required output. In fact, the guitar does not need to be in tune at all - you play the open strings to calibrate the initial settings, and the computer does the rest of the work (although it all works best if the strings are at or very close to normal tuning).
Guitar MIDI synthesisers also use hexaphonic pickups, and have a similar range of features with a wider range of instrumental sounds that could be performed.
Yeah I’m guessing if was circa 2000 he was using a midi setup and it was definitely aaphonic pickup.
He uses it to simulate other instruments too so that makes sense.
Thanks for the explanation, I want sure what terms to google.
Strange, I’d have thought the singing would be the difficult part. Assuming perfect pitch, you know what note you are singing, I guess. So if you have learned a song in a given key, singing it in a transposed key might feel odd? Or do you just tell yourself, OK, I’m singing this in (newkey) rather than the original key?
After starting capoed, at 1:28 JT changes keys by moving the capo in mid song.
I know a piano guy who likes the keys with flats: F, B flat, E flat, etc. I don’t know if that’s because they sound better of if it’s easier to play them. The easiest keys for guitar are the ones with sharps-G, D, A, etc.
I used to put on a recording and play individual notes to find the melody. That would tell me what key the song was in. If it were a difficult key, like B flat, I’d just capo 3 and I could play chords for G. Round up the usual suspects: G, C, D are the I-IV-V and then the minors would be Am, Bm, Em.
Once I figured that out, I could put it in different keys to suit my voice.
I can’t do that cleanly enough. I use 2-3-4 instead. I can’t barre a C, either.
There are some songs that will sound goofy if you don’t barre them. Sister Golden Hair comes to mind. And how about a moving capo—IOW slide guitar?
I don’t play slide but I understand they alter the tuning to a chord, like D-A-D-F#-A-D. Three strings…I wonder if he tuned it like a 5 chord, E-B-E maybe.