[Stratrat]

Man, there are a LOT of variables in that question.....but in general, a guitar equipped with humbucker (dual-coil) pickups will have a "fatter" sound than single coils. Different amps are voiced differently, even comparing tube amps to tube amps. A Mesa Dual Rectifier is going to have an entirely different tone than a Fender Twin, etc. It is true that tube amps are generally considered as "warmer" sounding than solid state amps - but there can be exceptions to that rule also.

Pedals can drastically change your tone - you talked about Hendrix having a fat, warm tone, yet he played a Strat with single-coil pickups. It's grossly over-simplifying things, but within distortion pedals you have 3 general classes - overdrive, distortion and "fuzz". A fuzz pedal will give the sound you're looking for. I believe the pedal he used (or one of them, anyways) was the Dallas Arbiter Fuzz Face (which Dunlop just released a copy of). Just about every pedal mfr. has a fuzz pedal on the market - Electro-Harmonix has the Big Muff Pi, Digitech has the "Hendrix Experience Pedal", and many others also offer them.