Parasound Halo JC 1 monoblock power amplifier Page 3

On Jones' spare, languid arrangement of Hank Williams' "Cold Cold Heart"—just her piano, acoustic bass, and a sprinkle of percussive accents on electric guitar—the picture was so cleanly and exquisitely drawn that I found myself playing it again and again, even though such repeats don't give the grooves a chance to cool down and almost certainly cause damage. (Can I have another copy, Hobson?)

Admittedly, the insertion of the SME 30 turntable added an unknown variable to the mix. The only way to discern the JC 1's contribution to the super sound I was getting was to put my reference Simon Yorke 'table back in the system, but that had to wait until I'd played dozens more discs—LPs, CDs, and SACDs—and sorted through a host of other sonic qualities that contributed to the overall picture. In the end, and without comparison to my reference, the JC 1 was actually on the subtly warm and rich side of the sonic spectrum—but not at the expense of transient speed and resolution of detail.

I usually find solid-state amps too bright and hard on top, or—when designers go overboard in their attempt to cure this problem—too soft and unfocused. The JC 1 was just about right: neither etched nor softened, but just far enough on the right side of "silky-smooth" to sound tonally natural and texturally complex. Good tube designs have a much easier time in this region, but, as the JC 1 proved, it is possible to get the balance just right with transistors. I've reviewed a tube amp that was brighter and harder.

When I reviewed the Musical Fidelity Nu-Vista 300 in November 1999, I thought its midrange was slightly cool. Over time, I've decided it was the midbass that was a bit pronounced, which gave me the mistaken impression that the mids were somewhat recessed. The JC 1 struck me as being tonally more neutral and somewhat more supple and detailed in the midrange. Its rendering of a mint RCA Living Stereo LP of Jascha Heifetz's recording of the Sibelius Violin Concerto (LSC-2435) demonstrated to me that the JC 1's midband purity and delicacy left little to be desired. Still, if you prefer a typical tube amp's midband lyricism, you might respect the JC 1 in this regard without falling in love with it.

When I listened recently to violinist Arturo Delmoni playing, in person, just a few feet in front of me, at an intimate speaker demo given by Aerial Acoustics, I noted the violin's combination of edgy sweetness and soft clarity. Too much midband bloom and an amp can make a well-recorded violin sound too warm and silky-soft. Too dry and analytical, and the instrument can sound creaky and "grindy," with too much of the literal physical act revealed and not enough of the act's intended effect. The same applies to the piano.

The JC 1 was tonally and harmonically convincing on well-recorded violin and piano performances. I played the Classic LP and JVC XRCD (JVC HR 0223-2) reissues of the Heifetz/Sibelius recording and was impressed by how revealing the Halos were of the differences between these reissues and the original. On the Living Stereo LP, the violin sounded harmonically intact and physically "feathery"—delicately textured and palpably real. Both the reissue LP and the XRCD CD had the violin sounding dry and screechy—though not at all bright—and harmonically truncated. The reissue LP and the XRCD made the violin sound the way doctrinaire tube lovers think solid-state always makes violins sound. Yet the original LP, played back on the same solid-state JC 1s revealed the "tubey" nature of the original LP's electronic chain.

With this much honest power available, it was hardly surprising that the JC 1 handled major-league dynamic swings with ease while maintaining rhythmic focus—something the Nu-Vista 300 manages equally well. More impressive was the JC 1's low-level dynamic presentation, aided, I'm sure, by its outstanding signal/noise ratio. Remarkable transparency and first-rate resolution of subtle, low-level dynamic detail helped make the picture painted by the Halo convincing and seemingly complete.

The Big Showdown
I'd asked to review the JC 1 more out of curiosity than anything else. I wanted to hear how another powerful non-tube amplifier would compare to my reference, the Musical Fidelity Nu-Vista 300. So it wasn't with any kind of burning anticipation that I substituted the Nu-Vista for the JC 1. In fact, I put it off for as long as I could.

But after five weeks of more than pleasant listening, it was time to compare what my ears had become accustomed against my reference. And there were a few other variables in the chain to be considered: the SME 30/2 turntable with Celebration cartridge, the Tri-Vista SACD player, a re-tubed Hovland HP-100, the substitution of Analysis Plus Solo Crystal Oval 8 interconnect and speaker cable, and the addition of the Shunyata Research Hydra power distributor and Anaconda AxV cable.

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James Trower's picture

Parasound JC1 power amplifier comparison to the newer Parasound JC1+ power amplifier.

I have owned many amplifiers over the years; I am saying 30 or more. I have had small 75 watt amps to much more powerful 500 watt amplifiers.
I bought the JC1 amplifiers in 2004. I had read many positive reviews such as this one in Stereophile.
Upon a few weeks of listening; I honestly thought there was a problem with them. The bass was so deep, and textured, I thought something was amiss.
The dynamic swings were on a level that shocked me. The ability to go to very high volume levels, without sounding like the volume had changed. They just would not distort at ridiculously high levels.
The bass issue still bothered me. I thought part of the circuitry had malfunctioned, and was causing bass that did not exist in the music. It just seemed too present, deep and growly.
I changed speakers, as I have no tone controls in my system. The same; just amazing dynamics, crystal clear high volume levels and truly amazing bass.
It took me a bit. It was the fact the JC1's provided a huge amount of current.
I had also read many reviews stating the bass was phenomenal. I was satisfied they were not malfunctioning.
I did quite a few comparisons to amplifiers reviewed and bench tested in Stereophile. I found that the maximum dynamic output of this amp is hard to beat by any amplifier tested.
Then came the review of the new Parasound JC1+. The bench test measurements for the JC1+, even though it is rated at 450/Watts (50 more than the JC1), showed quite a bit less maximum power into 8/4 and 2 ohms.
The maximum power output was:
The JC1 - 8/4/2 ohms power output was 586/1154/2255 and 4200 watts into 1 ohm.
The JC1+ - 8/4/2 ohms power output was 500/830/1200 and no testing into 1 ohm.
I think this very high output from the Parasound JC1 was responsible for the exceptionally deep base and very large swings in dynamics. I think it also has very amazing detail and imaging.
If you can find a pair (usually around $5000) grab them. They get an A rating from me on my 20 year listening quest.