Tannoy HPD 385A, HPD 315A, HPD 295A (1970s)
A series of integrated drive system loudspeaker drivers from Tannoy, used in classic British speakers of the 1970s and 1980s.
Overview
The Tannoy HPD series—comprising the HPD 385A, HPD 315A, and HPD 295A—were integrated drive system loudspeaker drivers introduced in the 1970s. These drivers formed the core of many of Tannoy's classic speakers from that era, including the Arden, Devon, and Berkeley models. Designed as a successor to the Monitor Gold series, the HPD line offered greater power handling and improved cost efficiency while maintaining the brand’s signature Dual Concentric configuration.
Design
The HPD series featured a "High Power Design" with a ferrite magnet, distinguishing it from the earlier Alnico-magnet Monitor Gold drivers. It shared a similar crossover design with the Monitor Gold line, reflecting a consistent engineering approach in Tannoy’s high-end passive networks. The drivers were noted for their robust construction and dynamic sound, contributing to what is considered a classic British audio character.
Context
The HPD series succeeded the Monitor Gold and was used widely across Tannoy’s speaker range in the 1970s and 1980s. While some audiophiles prefer the sweeter midrange of the Alnico-based Monitor Gold, others favor the HPD for its greater punch and dynamics. The series is regarded as iconic and legendary among vintage audio enthusiasts.
Market
Common issues with vintage HPD units include foam surround rot, drying ferrofluid in the high-frequency horn, and aging capacitors in the crossover. Refoaming kits and replacement ferrofluid are available from specialists, and re-capping the crossover is recommended for optimal performance. When refoaming, repairs should replicate the original factory method—installing the foam "under" the driver cone. The HPD series remains highly sought after by collectors and restorers.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.
Related Models
- Tannoy 4033 (1975)
- Tannoy monitor-red-iiilz-(10 inch) (1974)
- Tannoy monitor-silver-12 (2001)
- Tannoy inch3128-(12 inch) inch (1980)
- Tannoy 3828-(15 inch) (1980)
- Akai AM-2850 (1975)
- Akai AP-206 (1975)
- Nakamichi BX-1 (1985)
- Acoustic Research research-ar-17 (1978)
- Acoustic Research AR-19 (1994)