Bryston 7B SST vs. Parasound Halo JC 1 shootout...

Speaking of that Stereophile review; they mention that the JC-1 uses a 10 amp transformer - what is that equivalent to in VA? Wondering because putting out 4.2kW into 1 ohm (short term) is pretty impressive. If I remember correctly the Krell FPB-600 put out about 6kW into that load - serious company.

Well, if 10 amps is the rated input current then the transformer VA rating would likely be 10 X 120 = 1200 VA. The actual short term amplifier output will be significantly greater at 1 ohm, limited to a large extent by the storage charge in the bus capacitor bank. I think these peak power figures at 1 ohm begin to get a little academic since there are few speakers with impedance dips to 1 ohm and, even then one would have to be driving the amp relatively hard to run into trouble. Also remember that if you are using the classical solid state amplifier, or any amplifier using global feedback, you may not obtain even the rated output power in areas where, and if, your speaker has an impedance peak (most do to some extent). Amplifier output power ratings are not so impressive at 15 or 20 ohms so manufacturers generally never publish this figure. Amplifier manufacturers such as Innersound have capitalized on this to some extent by offering high output current capability as well as high rail voltages. This allows the amplifier to maintain its rated output power over a wider spectrum of speaker types and their associated impedance demands.

Again, a lot of this is academic so don't read too much into it. The 4 or 8 ohm rating is still the most important.

Don't let the JC-1's attractive appearance fool you into thinking they're mid-fi. What's under the hood is a polished design by the members of the CTC team, and the sonic results speak for themselves. I find my JC-1s drive my Sound Labs a lot better than my previous OTL tube amps. Of course YMMV, and yes I'm a dealer, but I don't see myself changing to anything else for a long time.

Brian Walsh

Well, I've not audtioned the JC-1, but I own the A21, which I understand is a notch (or several) below the JC-1. Before buying the A21, I was using a Pioneer Elite VSX-49TXi to drive my Dunlavy SC-1a/v speakers. I decided that external amplification might benefit my two channel music listening and thought I'd give the A21 a try, having read the favorable reviews of the JC1 and also a very favorable review of the A51 in DVD, Etc. All I can say is that the A21 absolutely blew me away. I realize that it may not be fair to compare a receiver (even one as superb as the VSX-49TXi) with a dedicated 250Wpc stereo amplifier, but I can say that there is no comparison, the A21 smokes the VSX 49Txi. Now I just have to save up to buy three JC-1s to use for my three front channels and let the A21 drive my surround channels and I will be in 5.1 heaven.

You got to put the CLasse CAM 350's or even the 200's in there!!