PASS Labs x350.5 vrs. Parasound JC1


Hello, I was wondering if anyone has had the pleasure of hearing the differences between these two amps that could offer their opinion on which one they felt was a better sounding unit?

I currently have a PASS X250 amp that I have been using for several years and really have no complaints on its performance but I am thinking of upgrading to something with more Class A output power.

I like the idea of amps that transition from Class A to Class A/B operation because they will ensure I have plenty of headroom during those aggressive listening sessions.

The current Pass X250 is driving a pair of B&W 803 Diamond series speakers. By my estimation, room size and listening habits it looks like I would need about 35-40 watts of Class A power to stay in Class A operation for most of my listening (90-105db).

The specs on the speakers call for up to 500 watts of unclipped power into 8ohms. I believe they can hit 3ohm at certain points so I want to ensure which ever amp I get can keep up with their needs.

Based on my research either of the two amps in question could fit the bill easily in terms of power with the advantage going to the PASS as far as more Class A output than the Parasound. My gut tells me to stick with PASS Labs and I can't go wrong but I have always had an interest in the big JC1 also. I like the fact that the JC1 has a seemingly endless supply of output power as the speaker load drops which the B&W's are known to do often.

Please post your experiences..Thanks
eniac26
Dracule, my first problem was picked up by my dealer (after one year), then returned to me repaired. Parasound has a record of that repair so I must assume they did the work. The recent failure I paid for shipping to Parasound (at 6.5 years old) and they covered the return.

I believe comparable Pass amps are of similar size/weight so not a consideration for the OP's question. However you may rule both out for this reason.
Like Pryso, I have owned a pair of JC-1s that I purchased new six years ago. They have a hell of a lot of playing time on them and I have never had any problem with them. I run them in the high bias position driving a pair of Duntech Princess speakers which go down to the 2 ohm range . Wonderful sound.
Violin
The JC1's are absolutely killer amps. Nothing against Pass as they are also outstanding amplifiers, but I'm a sucker for mono's and the big Parasounds are nearly impossible to beat at their price point.
Hi Pryso, sending a heavy amp for repair can be a pain, not just physically but also in shipping cost. Did Parasound pay for shipping both ways? Or did you have a local dealer do the repair?
Well Roscoeiii, each person may interpret any comment however they choose, but I find your "good reason to be concerned" a little bit of a stretch. Does that mean you always expect completely trouble-free operation over more than a five year period?

Here is more background on my experience:

- Upon checking I found I've owned these amps nearly 7 years,

- The same part failed in both amps, so it was one specific problem,

- The first amp failure happened within the first year, the other amp worked fine for over six years,

- Parasound stood behind their product and repaired mine in a prompt, fair and satisfactory manner, and

- While I cannot specify when Parasound realized this consistent part failure, once they did they upgraded that part (possibly all amps within the past six years?) in their new production.

As I said, this has been my only problem in nearly 7 years. Now with this upgraded part I'll guess that 80-90% of the used JC-1s and all of the new ones should be as trouble free as any mainstream product.
I'd call this a substantial endorsement.

http://www.empiricalaudio.com/about-empirical-audio/
But Pryso, I'd say that there is good reason to be concerned about your experience (and the experiences cited above) of needing to return both of your amps for repairs. Even one repair on each amp is not a good sign at all. If it was an early problem now resolved, it sure would be nice to know at what serial # the problem was fixed. Otherwise, knowing this history, I am inclined to steer clear.
After the comment on the Parasound reliability I had to respond. I've owned a pair of JC-1s for more than five years. Each one was returned for repair of a failed thermistor. Otherwise they have performed unfailingly over all those years. And as I posted separately, Parasound was outstanding in handling those repairs. My understanding is this failure was only a problem with earlier production, an upgraded part has been used for several years now.

Regarding the OP question comparing to Pass, I don't have any direct experience. But I can say I compared the JC-1s to many other competitors, both ss and tube, and found them superior in many ways. Also, I have found the high bias setting to provide the best sonics.
I have two friends that owned /past tense the JC1s,and both had build issues and the amps went back and forth several times for repairs.Two out of two...From what Ive read that was common.Cant comment on how they are now though.So I would never buy those amps,having said that IMO Pass is a no brainer.If class A is the key for you Id step up and get the 60.5 or if funds allow the 100.5 mono blocks.Pass also has better resale and is easier to move...but I would also dump the B&Ws as quick as I can say it so take this with a grain of salt!
I cannot comment on the Pass amps, but I am running two JC1s with my B&W 803ds. I routinely listen with these amps in the "high bias" position. I doubt if there is really much of a difference between 25 watts and 40 watts or so (actually only 2 dB). Remember you will extend out of "Class A" operation into Class A/B only on the music transients.

The JC1s never seem to have any problem driving the 3.5 ohm impedance of the B&Ws. I think they are stable into 2 ohm loads.