software

OK, so I'm looking at Musician's Friend at Peavey's post-5150 amp heads with like 6 12AX7s for producing gobs and gobs of gain, which is fine. However, when I use my little Ibanez Tube King (that has one 12AX7) with an amp with one 12AX7, I can get a very tubey, overdriven metal sound. Why doesn't Peavey (or another company) simply put a Tube King type circuit in their amps for the gain? I guess the fact there's a ton of op-amps in the Tube King makes it not-so-tubey, and traditionalists would not tend to like that in an amp head, but would rather the distortion come from a half dozen tubes. Sounds pretty similar to me though! You just don't see many one preamp tube high gain heads that also have power tubes.

Because, it's different strokes for different folks.

Although my Rivera has 5 preamp tubes, I usually only set the gain for 5 and use and OD pedal to drive it into distortion.

There is a difference in the type of gain you get by overdriving 1, 2, or 4 tubes.

Oh, also ...
Many amps that only use 1 tube also have a solid state gain stage in there as well, which to many people sounds WORSE than multiple tubes.