Pioneer PW-A31
A 30 cm cone woofer unit built in Japan with high-efficiency magnetic design and low distortion features
Overview
The Pioneer PW-A31 is a 30 cm cone woofer unit manufactured by Pioneer in Japan. It belongs to the A series of cone-shaped woofers and was designed for use in high-fidelity audio systems. This driver features a carefully engineered cone material and magnetic circuit aimed at reducing harmonic distortion while maintaining strong output and controlled resonance.
Specifications
| Model Rating Type | 30 cm Cone Woofer |
| Impedance | 8 Ω |
| Lowest resonance frequency (fo) | 20Hz |
| Reproduction frequency characteristic | Fo ~ 3 kHz |
| Max Input | 80W |
| Rated input | 40W |
| Output sound pressure level | 93dB/W/m |
| Crossover frequency | 3 kHz or less |
| Qo | 0.27 |
| Total flux | 178,000maxwell |
| Magnetic flux density | 10,700gauss |
| Equivalent mass | 57gr |
| Baffle opening | 270 φ mm or 310 φ mm |
| External dimensions | Diameter 340x Depth 156.5 mm |
| Weight | 6.7kg |
Design
The cone is made of carefully selected fiber material with high Young's modulus and moderate internal loss. A high compliance type roll edge is used for the surround. The magnetic circuit employs a large ferrite magnet and a long voice coil designed for good magnetic efficiency and uniform flux even at large amplitudes. A pure copper cap on the pole piece suppresses harmonic distortion.
Market
The Pioneer PW-A31 was originally priced at ¥14,000 around 1974, with a later listing at ¥16,700 around 1978. It appears as a listed item for sale on eBay, indicating ongoing collector interest.
eBay Listings
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