PS Audio HCA-2 Hybrid Class A Stereo Amplifier
This beautiful, high-quality black PS Audio stereo amplifier is for sale in 9/10 condition but I will rate it 8/10 for its classic status. It delivers 150 watts per channel into 8 ohms and is stable down to 2 ohms delivering 275 watts. Its hybrid design features a zero-feedback JFET input stage for pure voltage gain followed by a SDAT (Super Digital Amplification Technology) output stage with an oversized toroidal transformer that delivers current to connected speakers independent of the speakers' impedance variations with frequency of sound. The result is excellent audio performance with little heat generation as well as a great used value. To better its performance today you would need to compare amplifiers selling for more than $5000 new.
I’ve used the HCA-2 with electrostatic speakers (Quad ESL-63 and Innersound II), cone speakers (Vandersteen 3As, Von Schweikert dB99s) and several smaller speakers both in stereo and surround sound applications. Overall, its performance was comparable to more powerful and expensive CLASSE amps I've owned (CA-300 then CAV-180 on front channels): dynamic ease, background quietness, tonal neutrality, musical detailing, very good sound-staging, ability to drive difficult speaker loads, ease of operation, overdesign with quality parts for reliability, and attractive packaging. I've never experienced a problem. Being 95% efficient, it also saves you money on electricity, so it is a "greener" amp.
The speaker load didn’t matter in practice and its performance was exemplary with both electrostatics and coned speakers on classical, jazz and popular musical genres. You also have a choice of using RCA or balanced XLR connections, and quality speaker wire terminals. It was used regularly for about 5 years in a pet-free environment (about 15-20 hours weekly), then stored inside a house closet when I retired to a small home. I have just used it for a couple days now to verify its performance prior to sale and shipment. Included is the user manual, a power cable and the OEM box for safe shipment as shown in the photos. BTW, it looks better than captured in my reflecting photos.
Asking $675 for this rarely sold amplifier plus half of the FedEx shipping cost to continental USA addresses. Buyer pays an added optional $20 fee if payment is made by paypal. I will pay the Audiogon fees. Amplifier chassis is 17" x 14" x 4.5" and 35 lbs. Shipping dimensions are: 23” x 20” x 8.5” and 40 lbs.