Thanks. The rest of it is CJ 14 and 15, MR-78 tuner, and an old Philips CD-80. The CD player will be the upgrade after the bass amps are replaced. If you hear of any IRS-V's for sale, I'd like to know.
I had the Adcom GFA-565's rebuilt 3 yrs ago by a place called Big Sky Audio, Rick Krzemien. He replaced all the caps. We've agreed I'll send them back and he'll look them over. I'd like to fix them, and send them elsewhere as usable monoblocks. I won't have them back in my system. I don't expect they have a lot of value, and I don't expect to make much money here, but I also don't want to just take them to the junkyard. They're cosmetically perfect.
I've looked at the Perreaux Prisma 750. As Dave said above, I believe one needs an amp that "doubles down". The Perreaux seems to be a good candidate in that respect. I'm also looking for an amp that offers DC output protection, and that would include the Classe, Perreaux, and Spectral, and perhaps others that I don't know about yet.
Although the Perreaux seems to nominally fill the bill, I'm reluctant for a couple of reasons. First, they don't have much presence in the USA. Second, I need some amps that will work well with speakers I might buy in the future. I tend to favor established brands, even at the sacrifice of perhaps some ultimate audio quality, in the hope that 10 years or so down the line such amps would have some value, and also could be repaired if necessary.
It's been so many years since I was intimately conversant with the requirements of the Betas, but are the woofer towers the ones whose impedance drops very low, and require the current levels that these "welder amps" such as Perreaux offer?
Thanks for your input.