Lanny, the Parasound Halo JC-1 amplifiers are heavily based upon the earlier HCA-3500 stereo amplifier which you own, but there are differences significant enough to make for major improvements in the sound. The power supply is much larger, there is a lot more heat sink, and so on. Parts were selected carefully to voice the amplifier correctly, and substitutions for those specified have not been acceptable. Additionally, the circuit board layout is vastly improved. I won't go on other than to say an audition is highly recommended, and I suggest listening to a broken in pair if possible.
Brian Walsh
Brian Walsh