CJ pre-amp with McIntosh amp?

Yes the 2500A is more than just a power increase. The "A" upgrade adds more PRAT to the standard 2500. I had a 2500 which I had upgraded to the "A" level and the improvement was not subtle. If you like the cj sound you probably won't lke Mac at least I don't but that's my taste.

Chuck

There are a couple of 2500's for sale now for around $1500. would it be worth it to buy one and send off to CJ for the A upgrade?

I would ask cj for the cost of the upgrade. When I had mine upgraded it cost $500.00 plus shpping to them; they covered the shipping back to me. Hard to say whether it is worth geting one upgraded or wait until an "A" pops up. An original factory "A" model will be newer although if you send the unit in for an upgrade cj will go through it to make sure it is up to specs. I guess it depends on how much of a hurry you are in.

Chuck

Maybe I should just get the upgrade for my 2250

Another thought . I don't know if you would or ever considered a tubed amp but there is a premier 11a available on this site right now (no association). I had one paired with a pv-10 driving a pair of thiel 3.6's and it sounded wonderful. I will have more guts than your 2250 and be more musical even with the "A" upgrade on your 2250. The 11a also holds its value extremely well.

Chuck