Best upgrade option might be the wife. ;-) That would allow you to try the most cost effective upgrade which would be to have your current amp near the speakers, run short, better quality speaker cables and then run longer interconnects (ideally balanced if the amp/preamp allow) to preamp.
Seriously, if you can borrow some cables from a friend you might even try this out and see if it helps much before you decide about any major investments. Then blindfold the wife and beg her to listen to the improvements.
FWIW, I'd say a fair price for your friends Cary amps would be 25% of MSRP if the current tubes have significant life remaining. If they need replacing, I'd then say split the cost of the tubes 50/50. The biggest downside is that since KT88s have been supplanted by KT120s and now KT150s, more modern amp designs let you take advantage of far superior sounding tubes, so they better be a great bargain or you are getting the short end of the deal. Cheers,
Spencer
Seriously, if you can borrow some cables from a friend you might even try this out and see if it helps much before you decide about any major investments. Then blindfold the wife and beg her to listen to the improvements.
FWIW, I'd say a fair price for your friends Cary amps would be 25% of MSRP if the current tubes have significant life remaining. If they need replacing, I'd then say split the cost of the tubes 50/50. The biggest downside is that since KT88s have been supplanted by KT120s and now KT150s, more modern amp designs let you take advantage of far superior sounding tubes, so they better be a great bargain or you are getting the short end of the deal. Cheers,
Spencer