Parasound JC1's vs. Sim Audio W10

Cadougie - there are a couple of reliability things that could use improvement, mostly in older used JC-1's. Parasound is aware of these and some of these have been improved in the newer versions. I'm surprised that you had problems with a recent amp - perhaps it was from an older build lot.

I resolder all of the power transistor solder joints because some of these are not good in the older amps. The open-frame pots used for the bias adjustment seem to drift (or the other components drift), and finally, the inrush limiters do not have a lot of margin, so I use higher current versions. Once these things are changed, it is a very robust amp. I have had mine for several years and use it every day.

Bob. What is the difference between high and low bias on a practical and sound quality level?.

thanks Shane

Hi Shane,

In low bias the unit will go into AB mode at about 10w which is audible with my Rockport speakers and isn't in high bias which allows about 30w of class A. I normally run the amps 24/7 in low bias and flip the switches to high bias when I want to listen to anything above tuner level......This saves a bit on heat and electricity and is a useful feature on this large amp........

Bob,

Is it ok to turn the JC-1's on and off every day or does it take to much of a toll on them? I prefer to do this but certainly do not want to hurt the amps. Thanks for your responce

Break in time. Bob I am going to have listen one more time to a pair of JC-1's in the next couple of weeks.

What is the minimum play time until these amps will show most of what they are worth and sound pretty nice.

I had a listen to a pair 6 months ago and frankly was underwelmed - they had about 100-150 hours on them and I ran them in for another 50 of so. The dealer in total has probably only put about 300 hours max even now. He much prefers the sound of the moon W5 and has dismissed the JC-1's as he believes the long play time as garbage.

Bear in mind that the dealer is not going to let me play these amps for 1500 hours, and I am not going to buy anything on the promise of fundamental changes in sound at a later stage.

I would appreciate your honest oipen opinion as always.

cheers Shane