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Greg_L
Banned
On the subject of the original post.
I dont know the percentages of preamp/poweramp/speaker contributions to the sound, but I know this;
The power amp tubes cooking is very important to the tone. A lot of what people consider to be the holy grail guitar tones were done with pre-master volume amps.
The power amp is very important in the good tone equation.
You know, the Marshall JTM45/Plexi/Super Leads are probably the quintessential, most often considered non-master-volume amps that have become legend because they were so loud and had famous users and all that good shit. They're generally highly regarded for their power amp distortion. The thing is though, they actually had very tight power sections. They had a lot of negative feedback. The power section stayed as clean and tight as it could for as long as it could until it just couldn't handle the power anymore. It was common for people to mod the negative feedback loop to break up the power section sooner. A good chunk of their goodness did actually come from the preamp design and phase inverter meltdown. The "volume" controls on those amps were basically just gain knobs. The amps were stupidly loud whether you had them on 1 or 10. Those old transformers contributed too. Not to mention they were most often partnered with huge cabs full of Greenbacks. They sounded killer because it was just a magical combination of things that just worked together to set the table for everything to follow.