Parasound JC-1 - How old is too old?

I've owned the JC-5 for about five months now. Very nice sounding and way more power than I need with my efficient speakers.

I had a chance to listen to the JC-5 and an older pair of JC-1s on the same system. I thought they had a very similar sonic signature, but I had a slight preference for the JC-5 on the system I was listening on. I wasn't familiar with the speakers, but the dealer said they were about 90db/w efficient.

I suspect lower efficiency speakers would benefit more from the higher current capacity and higher class A bias of the JC-1s, but on the more efficient speakers, the JC-5 had smoother, clearer vocals.

i used to have th JC-1s, great amp, with tons of power.

i would not be too worried about dried out caps. the factory installed some pretty good caps, even on the earliest units would likely still be good, but if you want to put concern to rest, meas the ESR and cap values on each. that will tell you for sure if you are good

what about the new jc1's?

So how does the JC5 compare to the JC1?

Well, I went down to the dealer this morning to check out the amps, and one of them had stopped working just before I got there. The amps were produced in 2007. This convinced me that I really didn't want to deal with an older amp again. 

I mentioned to the dealer that I was also interested in the JC-5, and he offered me a good discount on a brand new one. So I went for it. Should have the amp by the end of this coming week.

Thanks for all the replies. Makes me feel a bit more comfortable buying an older unit. 

Electrolytic caps made in the 1980's were not nearly as reliable as those made after 2000.


30-40 years may be a better time frame for new caps. Also, temp ratings matter. Higher rating = longer life, so when you upgrade, see if higher temp caps are available for the main power supply filter caps.

O...M...G! Did somebody just mistake me for George of the Jungle? Whoa, Daddy! 😦

Oh and don't forget to tell us what you think of them.

and get to it fast. They will not last long!

Hot enough that you would not want to keep your hand on the heat sink.

I measured them at high bias (28c ambient) at 55c, internal was the same, no problem for those excellent Japanese Nichicon Gold caps. So don’t worry OP buy them.

Cheers George

Geoffkait, they run class A to 25 watts into 8 ohms. For some reason this is a magic number for John Curl. After that they run class B. Run on full bias they still can get pretty hot. Hot enough that you would not want to keep your hand on the heat sink. At 1/2 bias they are just warm but most of us think they sound better on full bias even the bass for some reason.
Jaytor, mine are 6 years old. But as Geoffkait implies these amps are built much better than any of the older Krells. Also the circuitry and layout were done by the best in the industry. In this price range it simply does not get any better. Once these amps are proven, have run for a period of time without issue they are good to go for decades unless you throw one out the bathroom window. 

I isolated four of the first JC-1s in John Curl and Bob Crump’s room at CES in early 2002 which would make the (first) JC-1s almost 18 years old. 

If anyone has re-capped their JC-1s, how old were they, and how much
did it cost? Thanks for the help.

Even if you got the first ones, they’d still be good for another 10-20 years.
They used quality caps, Japanese Nichicon Gold.
https://www.parasound.com/jc1.php

I feel that age is particularly important with Class A designs. All those components have been living in heat their whole lives.....

And they’re not Class-A but 400w A/B and run cool in normal mode, they have high bias switch on the back which gives them around 25w Class-A bias still with 400w B, then they run warmer, instead of 10w A and 400w B in normal mode and cool.

BTW great amps, I heard them many times on Wilson Alexia and nothing but the top Gryphon Antileon Evo could equal them, and the Gryphon "just" surpassed them at many $k's more.

Cheers George

@mijostyn Thanks for your comments. That's very helpful. How old are the JC-1's you are using?

Jaylor, as I said above these amps can not overheat. If someone was silly enough to put them inside a cabinet they would just keep shutting themselves off. I had a pair of Krell KMA 100s which was made with output devices not near as sophisticated as the ones used in the JC 1 and they lasted 23 years before blowing an output stage. I would have no trouble buying a 16 year old pair if the price was right. 

I have a pair of JC 1s which are now driving my subwoofers. I used them on my ESLs for many years and I can tell you that there are very few amps that perform as well and the ones that do cost way more. They may go down as the amplifier value of the century.  No JC 1 is old enough to need new capacitors at this time unless the amp was damaged. As long as the amps are running as advertised and there is no evidence of physical damage you should be good to go. They are built extremely well and use extremely high quality output devices. The thermal cut off is set pretty low so there is no way they can be damaged by heat. They would just shut themselves off and flash a red light at you. I see no reason why a JC 1 should not run reliably for 30-40 years maybe more. 
Sound wise these amps have an airy effortless like a high powered tube amp but the fist of a high powered solid state amp. God knows how John Curl does this. I'd love to hear some of his Constellation designs. Of all the amps I have been able to hear in my system only Pass amps have that airy effortlessness that I find intoxicating. The JC 1 has phenomenal
(better) bass which is why they wound up on the subs and boy do they do a honking job of it. Unless you are use to hearing high powered Pass, CH, Boulder, Soulution, or Moon amps these things will absolutely blow you away. 

Mike

Yes, that is part of my concern, particularly if the amps were used inside a cabinet which did not provide adequate ventilation. No way to know on a used amp. 

I owned a Krell FPB-300 (which also ran warm) that I had recapped when it was about 10 years old (only because it was in for service for a broken speaker connector) and it started giving me problems after another 10 years. The cost of repair at that point was prohibitive so I traded it in to a dealer that wanted it for parts. According to a dealer I talked with, failing caps was not uncommon with this series of amp.

Since the JC-1 has been around for 16 years now, I'm worried that an older pair is probably close to being in need of repair even if it was treated well its whole life.

But I'd like to hear from folks that own older units to understand what their experience has been.

I checked with McIntosh before I bought my used components and was told 20 years, unless they are bulging or leaking, then immediately.  Not sure for other brands.

I feel that age is particularly important with Class A designs. All those components have been living in heat their whole lives.....