Parasound JC1's vs. Sim Audio W10

Gladstone, I run my JC-1s in high bias 24/7 and have for a couple years for both my Rockports (an easy load) and my Sound Lab M-1s (tough load) and curious what speakers are a tougher load than the Sound Labs? I chose the parts in the units and will say that those cheap Superior Electric posts cost five times as much as what is normally used by Parasound, are the originals that everyone copied and eat things like the WBT, Edison Price and Cardas binding posts. They were chosen for their performance, not their pricing. The JC-1 is what it is, a very powerful amplifier that can be machine built in Taiwan using specified parts that also sounds very good.........Sure we could do better if the retail pricing was 25K/pr........

Bob Crump
CTC Builders

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