Accuphase P-260 (1979)
Stereo power amplifier with switchable pure Class-A operation, released in April 1979.
Overview
The Accuphase P-260 is a stereo power amplifier manufactured by Kensonic Laboratory, Inc. (later Accuphase Laboratory, Inc.) in Japan and released in April 1979. It delivers 130 watts per channel into 8 ohms in normal operation and switches to 30 watts per channel in pure Class-A mode, eliminating crossover distortion. Designed for high-fidelity reproduction, it features MOS FETs in a parallel push-pull output stage and includes an attenuator for precise input level control.
Specifications
| Power Output (Normal, 8 Ω) | 130 W/ch |
| Power Output (Class-A, 8 Ω) | 30 W/ch |
| Frequency Response (Rated Output) | 20 Hz – 20,000 Hz +0 -0.2 dB |
| Harmonic Distortion (8 Ω) | 0.005% or less |
| Damping Factor (20 Hz – 20 kHz) | 80 |
| Input Sensitivity / Impedance | 1.3V / 50k Ω |
| S/N Ratio (A-weighted) | 120 dB (rated input, shorted) |
| Power Supply | AC100V 50/60Hz 218W |
| Dimensions | 445 mm (W) × 160 mm (H) × 390 mm (D) |
| Weight | 19.7 kg |
| Country of Manufacture | Japan |
Design
The P-260 uses MOS FETs in a parallel push-pull output stage, originally Hitachi 2SK134 and 2SJ49. All amplification stages employ Accuphase’s proprietary symmetrical push-pull design, and the circuit removes capacitors from the NFB loop to reduce distortion. Class-A operation is engaged via a pure electronic switch (PAT, PEND), not by adjusting bias resistance, ensuring seamless transition. A thermal sensor activates at 70°C to regulate bias, and the power supply uses a high-efficiency CI core with dual balanced windings. Two 40,000μF filter capacitors provide stable power delivery.
Context
The P-260 was released during the "Golden Era" of Japanese high-fidelity audio. It is listed among Accuphase’s "Classic Models Reference," following the company’s founding in 1973 with the P-300 amplifier and C-200 preamplifier. Originally branded under Kensonic Laboratory, Inc., the company later became Accuphase Laboratory, Inc.
Market
The P-260 was originally priced at ¥200,000, with an optional wood cabinet (A-8) sold separately for ¥15,000. Common issues include LED failures (D3, D4), DC offset instability, distorted output in one channel, and damage from water or prior repairs. A schematic is available on hifiengine.com, and component D3 is identified as TLR120.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.
Related Models
- Accuphase A-20
- Accuphase A-20V
- Accuphase A-45
- Accuphase A-50V
- Accuphase A-65
- Luxman L-530 (1975)
- Luxman R-404 (1975)
- Luxman RV-371 (1975)
- Luxman SQ-38U (1975)
- Luxman T-14 (1972)