Parasound HCA-1500A Restoration and Upgrade

Materials: Parts list can be seen here.

Background: This is one of a series of solid state amplifiers designed by the legendary John Curl. Mr Curl has frequented various audio forums from time to time, and made recommendations for improvements on how his original designs were manufactured.

Restoration and Upgrades: This amplifier was non-working. All capacitors were upgraded, along with some resistors and other components. Several circuit changes were made, as well. The above spreadsheet provides a full list of updated components.