Ask any touring pro and they’ll tell you the same thing; the road is tough on tube amps, and it is not just the constant moving around and hot and cold environments they are exposed to.
Not all mains power is created equal, and so when travelling across borders – or even from venue to venue in the same city – the power your amp is receiving is not always going to be the same. And if the amps are not receiving the same power each night, they won’t sound the same.
