Re: low output pickups with high gain amps, and vice versa
As far as Yngwie goes, well honestly his rhythm guitar tone is terrible.
Absolutely no meat to it and quite frankly I'd be embarrassed to have recorded rhythm guitar tones like that.
Dave Mustaine's signature pickup is actually quite high output.
Speaking of rhythm tones, the tone on Endgame......now that's an actually quite good rhythm tone.
EMG's unique combo of a low-wind pickup that's boosted to high-output resistance via preamp is the ideal gain structure, IMO - nothing else is as tight or clean while still being smooth and controlled. I honestly think that EMG's sound far more natural than a high output pickup into a high gain amp, and low output pickups just aren't tight enough into high gain amps IMO.
Indeed, ever since I got my Schecter C-7 Hellraiser I prefer the EMGs for high gain rhythm tones.
Although the Blackouts in my Ibanez (combined with the shorter scale length) seem to just sound a bit nicer on leads.
For high gain it depends on the music. If you are doing YJM/Vai/Satch you probably want lower output pickups through high gain (though Vai does the opposite). If you are going for heavier tones though the low gain p/u don't work. They just get too warm and muddy and lose their definition. That is why a lot of metal guys go active. I know there is always a debate on here that "low output" p/u always sound better but that isn't entirely true. If you want warm earthy tones sure. You need definition and clarity and big bottom those low gain p/u mush out.
Satch tends to use medium output pickups.
He's been spotted with his custom JS series guitars with a triple single coil setup, on the Experience Hendrix tour and I imagine that would be a bit lower output to get more of a Hendrix-y vibe.
Also, his PAF Joe pickup, that came out I think it was 5-6 years ago, is a little lower output than his PAF Fred pickups, so it seems as he's gotten older he's liking the sound of lower output more.
He's always been a very bluesy guy (and even though he can shred, IMHO he's a fantastic blues guitarist too), so it makes sense.