Proceed Levinson HPA-2 250 x 2 / 500 x 2 Amplifier near San Francisco, CA..................

This is an offering for a Proceed HPA-2 amplifier.

The HPA-2 was the top of the line flagship Proceed amplifier and was named in the top 10 for amplifiers of the year in 2000, a list that included the Krell FPB-600 and Mark Levinson 336.

This amp is in great operational condition with surface scratches/logo missing from front (sticker fell off).

Some design features of the HPA-2 include a proper dual mono dedicated power supply including twin 663 VA toroidal transformers for a total power supply in excess of 1.2kVA. The power supply capacitors are mounted directly to the printed circuit board rather than using point to point wiring. The layout of the circuitry uses short, thick traces for high current paths Each channel of the Proceed amplifier uses twelve 150 watt power transistors. These transistors are all individually tested and sorted, and are used in matched sets to ensure that no one transistor bears a disproportionate part of the overall load.

Rated power output: 250 w/ch rms 8W, 500 w/ch into 4W.
Frequency response: within 0.15 dB from 20 Hz to 20 kHz
Signal to Noise ratio (main outputs): better than –80 dB (ref. 1 w)
Input impedance: 100kW (balanced) 11kW (single-ended)
Voltage gain: 23 dB (balanced) 29 dB (single-ended)
Input sensitivity: 3.17 Vrms for full rated output (balanced), 1.586 Vrms for full rated output (single-ended)
Shipping weight: 94 lbs. (43 kg)
Connector Complement:
two binding posts per channel
one RCA input connector per channel
two 1⁄8" mini-jacks for remote turn-on and loop-through
two RJ-45 modular connectors for PHAST™ communications
one IEC AC mains connector

Output impedance: less than 0.05W, 20 Hz – 20 kHz

After Madrigal discontinued the Proceed line the transformer locations were changed and the HPA-2 became the Mark Levinson 431/432 series of amplifiers