I've recently got a new amp that the builder said would sound significantly better after a period of 40-80 hours. Sure enough, when i first got it i was underwhelmed, but now (after about 40 hours on it) i love the thing and the sounds i'm making with it. It's an extremely simple amp V,T, B,M, so it's not that i'm figuring out how to dial it in, i just am loving the sounds i'm getting out of it whereas before they were a bit harsh to my ears. I've usually been someone who buys used in the past, so i guess i've never had to really examine this idea before, but i'm beginning to wonder if a "burn in" period is true for all amps, and if i might of dumped a couple of really nice new amps prematurely (and am about to do the same with another, not the amp in question), before they had found their voice. I'm not talking about speakers, btw, i'm convinced they do change with use. I would imagine the effect would be stronger with amps that go for a basic, unprocessed sound, rather than one with a bunch of options, but who knows? What say ye?