Re: Guitar Amp w/ thick low end
I used a Ampeg V4 back in 70’s driving two V-2 cabinets and later changed to one V4-B cabinet and one V-2 cabinet monster tone machine with globs of bass, miss, and high end.
V4 had four toggle switches and you could set up the mid-range easy, easily pushed more than its 100 watts rating.
When I used it for a few hours, the power output always seems to decrease and tone drifted from loud and clean to a slightly softer (for lack of a better word) tone.
Power tubes 7027A were very hard to find even back then.
A friend gave me some KT-66 tubes, which I resisted using until he switched them without telling me. Those KT-66 sounded really nice, right up until they burned out on stage.
Got married, divorced, brother-in-law (Not same as ex-wife’s brothers) is holding all this equipment for me in Norfolk, VA.