From my understanding (oh so limited) .... No matter tube or transistor, the scope doesn't know nor care which it is. All it cares about is that things are sinusoidal and the spectrum analyzer only care that it's on frequency.
*edit to add*
So they're both going to sound identical according to how they look on a scope....unless you're over driving one to make it match the other, then of course the over driven one will sound worse.
*edit to add*
So they're both going to sound identical according to how they look on a scope....unless you're over driving one to make it match the other, then of course the over driven one will sound worse.