nakamichi vs threshold

Thanks for the answers.
Tonykay, what do you think about the differences between PA5 and PA7?
I am asking myself : Maybe PA7 is a bit over dimensionned for me, too much heat, too much weight... ?
Will the additional power improve the sound on JBL L112 ? (89db efficiency)
My listening room leasures 25 square meters.

I've heard a good number of technicians comment about that design- as I understand it, it is one of Nelson's earlier designs but due to construction or other factors did indeed have a reputation in the service industry (I ran a service shop for 15 years before going into the manufacturing sector) for stability issues.

These days if one has survived I would expect that filter caps should also be serviced out, but there are a lot of amps that are more deserving.

A buddy of mine had the PA-5 I think it was. Great sounding amp. I remarked over and over how good I thought the amp was. If it had reliability issues I know for a fact he never would have purchased it.

I owned JBL Olympus speakers in the 70s and 80s but I'm not that familiar with the newer models. At 89db, you should not have any trouble driving them with either the
PA5 or PA7. As I'm sure you realize, the 5 is simply a junior version of the PA7. For the extra couple hundred dollars, I would get the PA7 so that you'll have enough power down the road if you should get any of the newer, power-hungry designs that are being offered today.

Nakamichi stuff tended to sound great but SOME products had reliability issues. DO not know about that particular one.

I had a later day Nakamichi CD changer and head unit for my car. The CD changer had issues. The head unit which included the amp worked fine for years. Best sounding car stereo I ever had! I wish it still worked and I still had it.

Myself I'd be sure to confirm the history of any particular Nakamichi item from a reliability perspective with the seller if possible before dropping a lot of cash.

Older gear is always subject to more issues. Nak is no exception. The market tends to reflect that. Items like CD players, record players and tape units that have moving parts are usually the highest risk.

When Nak amps work, its generally good sounding stuff. Its worth consideration if the price and history is right, or if the seller will offer a money back guarantee perhaps, but be careful and protect yourself whenever buying used, especially with vintage gear!