I am just curious: what's the difference in sound between a 3 gain-stage distortion at high distortion, compare to a 4 gain stage that have a lower volume?
Ibanez SA-120 (ed.2006)
BluesJr 1996-B + cathode follower + texas Heat
Crate CPB150
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Metal Muff
Simplified (this is not 100% truth, but it's to make it easier for you to imagine and for me to explain):
Take three pedals, put them all after each other: three stages.
Take four pedals, put them after each other: four stages.

When someone says a pedal has X amount of gain stages, that's pretty much what is meant, that is the pedal has X amount of stages the signal goes through. It does not mean that it will have more of less gain in total, or that it will sound better or worse, it'll just be different.
I don't think there's a straight answer to this one.
More gain stages (ie preamp tubes) -> more gain. Higher volume -> more gain.
If you run 3 tubes at high volume you could possible have as much gain as 4 tubes at lower volume. But if it will sound the same depends on the kind of tubes, amp wiring etc..
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