Nakamichi PA7 versus PA7 II


What is the difference between Nakamichi PA7 and PA7II?
Also,are this amps classA?
Thank you
walther
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This is a great amp, worthy of fixing up

I spent about as much as you did in 2021 to refresh my MKII.

Absolutely worth the investment.  

The factory set bias of 40 mA will allow approximately 16 watts in Class A and, yes, it will be warm at idle but not hot. Unlike the Threshold's of that era where bias was set at 100 mA allowing 25% of rated power to be in Class A, however they were hot to the touch at idle and component reliability/longevity suffered greatly.

My tech also prefers the the MKII vs. the original and prefers the Naks over Thresholds for build quality and component selection.

I bought my Nakamichi PA-7A mkII in 1990 for $2200, and it’s still one of the best amps I’ve ever owned. After about 20yrs tho, it was sounding dark and sluggish, so I took it to a Threshold expert, and he recapped the whole thing (not cheap! $1400) but what I got back was like a $5k Threshold! It sounds glorious, and adds a certain glow to the music. I had to stop using it many years ago due to a nasty turn-on thump, and I’ve actually just taken it to a tech to get it fixed.

I recently got a pair of Cornwall IV’s and my Bryston 4B-SST2 is just too harsh and brutish for them (not surprised). I tried a Schiit Aegir2, and it sounds REAL nice on the Cornwalls... very smooth and easy, but ultimately still not quite right. THEN I pulled out my old Nakamichi, and it sounds FABULOUS on the CW’s! Yes it’s way too much power, but it simply has a certain magic to it. I can’t wait to get it back with the turn-on thump fixed.

For those that claim... oh it’s a hot amp, or oh, it’s a cold amp.... well.... it is however you set the bias! It runs many watts into Class-A. The guy that recapped mine set it so it runs pretty warm, and I can attest it’s smooth and dynamic! BTW... he also replaced the bias pots, as the originals, after 20+ years will be noisy and impossible to adjust smoothly. This is a great amp, worthy of fixing up.

The Threshold tech also told me that the MkII version is THE one to have. Nakamichi addressed many issues in the revision. Just look at the wiring in the first version vs. the MkII. They really cleaned up the power supply.

I have a PA-7Aii. I've run it with Magnepan MG3a's and Martin Logan CLS's -the first generation that are difficult to drive. It runs warm, not hot, but drives both speakers very well. It is a little cold blodded and sounds best after it's run for 45 minutes or so and sufficiently warmed up.

They are both excellent amps. And, consmetically speaking, among the best looking.

Can it do well with thiel cs 3.6? Dips to 2.5 ohms for 65% of its frequency range.
" The PA 7 ran into class A, more than the PA 7II, which meant, a warmer sound than the PA 7II. "
Total BULLSHIT
I own a PA 7ll and Ive listened extensively to a PA 7  The ONLY difference between the two is the upper wiring, the latter being a birds nest of wires aka "Cottage industry" wiring vs Nakamichi's professional job of cleaning it all up and adding a few more watts.
BOTH amps are stellar and neither is "the ONE to own", they BOTH are.
Just sold my beloved PA7 was the original owner and had it for 25 years. It was a very balanced amp with a beautiful and detailed midrange. I dont believe you can find a better amp for $700 - 900 dollars. Never had one problem with it and was still sounding like the day I bought it when I sold it.
Once had the PA 7, which I bought used. The sound is quite dynamic, supposedly better than the later model II. The PA 7 ran into class A, more than the PA 7II, which meant, a warmer sound than the PA 7II. Eventhough it had about 200W per channel, it did not well with too hard of loads comparatively with other 200 watt or 100 watt high current amps I have had experienced. All in all, if you get a unit for about $800-900 range, I doubt it can be beat for the money...even in comparison with amps that can be had up to 3k.
Nak tape decks may be great, but they are made out with plastic skeletons, therefore prone for mechanical failure (I.e: Dragon.)
stay away from nak amps

they are not musical for the money

stick to their tape decks

tom
Walther,

I think it's a fine sounding amp. I had it modified by Musical Concepts. I'ts not bright but maybe a touch warm.
A good power cable (I use Synergistic Res Ref) makes a
positve improvement.

Tim
This is related to the "Stasis" topology sound. I have a TA-4, the 100 w/ch reciever of the same Nelson Pass series. A nice amp with lots of guts, I use it in my video set up. For audio, when compared with other components it was more than a little rough. I know the PA 7 is a different animal, I'm just saying: listen first, buy later. (unless you are price/resale protected) good luck.
I have a PA 7 II and love.I run it hard into PSB gold's and it works ver well.
Thanks for your feedback.How do like the amp?Considering the age of the amp doesn't need new capacitors?
As the owner of a PA7 II can tell you it was rated at 225
Watts per channel into 8ohm vs 200 for the PA7. I don't believe they're class A but the do utilize the Stasis topology designed by Nelson Pass. This amp runs warm but not hot so if it's class A it's only at a small percentage of the rated power. That's all I know on the topic. BTW the PA7 II is rated at 325 into 4 ohms.