Let's suppose that the 47 lb amp sounds a little better than the 13 lb amp I just purchased. Let's say that it has a bit more weight/authority in the bottom octaves. Speaking for myself only, I'm willing to give up a bit of ultimate sound quality for the 34 lb difference. I believe there
could be a sonic difference between the amps in question. I don't have the luxury of comparing the 47 lb amp and the 13 lb amp in live situations over an extended period of time. If I did have that luxury, I would likely choose the lighter weight piece of gear, anyhow. But that's just me. YMMV. MOD (mine often does).
One thing I've learned through the years...those who think power amps sound different from each other and those who hear differences in cable will always feel that way. Those who don't hear differences between amps and between cables will always feel that way. I don't care who thinks what. I'll let you discuss among yourselves. And I don't care who is right. I'm just going to enjoy my bass rigs and play my butt off. Carry on, mates.
M. M.