*None of this is to say pedals are bad or inferior*
I would like to chime in on this Pedal Sound VS Amp Sound because IMO everyone so far seems to be wrong to some degree.
IMO, yes, a distortion pedal will leave a distinct sound on an amp more-so than the amp itself, simply because the amp is more than likely going to be relatively clean when you use a distortion pedal. The amp might darken it or brighten it, but it will be the pedal making "the sound".
An overdrive would be an amp that is already being driven hard and the pedal drives it harder, so more of the amp is coming through. That doesn't mean the OD pedal won't impart some characteristics though. That is not to say a distortion pedal can't be used to drive an amp hard like an OD, but if anyone has ever distorted a distorted signal, its not going to display a good example of either distortion source. It might sound raunchy and badass, but neither will be well represented as the major source of "the sound".
None of this says that the amp doesn't matter, but unless the amp is distorting, then it is the less crucial part in measuring the base of "the sound". I know people are saying a tube amp on clean with a pedal will sound different than a JC120 on clean with the same pedal. It will. But it won't remove the pedals characteristics and the distortion (not the tone) will be the same because the pedal is what is creating it. The tube amp may roll off some of the high end, but you will still be able to tell they are the same pedal, and the pedal would be 80% of the sound.
A tube amp on the verge of break up will
generally sound better with most distortion pedals than a clean solidstate amp to a lot of people, and that is why Jimi and others got such great tone from a simple FuzzFace. But that doesn't mean the FuzzFace wasn't the key to the sound.
Did that make any sense?