PYE Provost HF25 Amplifiers:
The first instinct with rare vintage equipment such as PYE HF25 amplifiers is to leave them as close to original as possible. Unfortunately there were so few remaining original components, rebuilding was the best option. They were powered up to verify working state before dismantling.
Many thanks to Jeff at the audiomods.co.uk/ website for providing invaluable information required to get started rebuilding the amps. In addition to the schematic, parts list, and component layout on his site, he provided scanned copies of the owners manual pages, and detailed information about the original parts.
(The owners manual and other documents in .pdf format linked below are comprised of scanned originals provided by Jeff.)
PYE HF25 Rebuild Completed – January 2017
As of January 2017, the rewiring and refresh of these PYE HF25 amplifiers is complete. They are fully operational again. The sound is dynamic; detailed, and airy with only 6 hours of use.
Amp SN# Ending 150
Amp SN# Ending 323