An amplifier built at the same time as the advent of quadraphonic systems. The Japanese equivalent of the Western QL 600A.
It is a bridge unit, that is, a device engineered to meet the needs of those who already owned a stereo system and wished to switch to quadraphonic sound without having to replace the components of their system. By
connecting this amplifier to a traditional stereo system, it is possible to achieve quadraphonic sound.
Quadraphonic sound (or quadrophonic and sometimes quadrisonic), equivalent to what is now called 4.0 surround sound, uses four audio channels in which the speakers are positioned at the four corners of a listening space. The system allows the reproduction of sound signals (in whole or in part) that are independent of one another. Four-channel
quadraphonic surround sound can be used to recreate the highly realistic effect of a three-dimensional experience in a live concert hall at home. It can also be used to enhance the listener’s experience beyond the directional limitations of normal two-channel stereo sound. Quadraphonic audio was the first consumer product in surround sound. Since it was introduced to the public in the early 1970s, many thousands of quadraphonic recordings have been made.
Quadraphonic sound did not achieve widespread commercial success when it was first introduced due to a series of technical problems and format incompatibilities. Four-channel audio formats were, in fact, more expensive to produce than standard two-channel stereo. Playback requires additional speakers and amplifier channels. It may also require specially designed decoding equipment.
A quadraphonic system will reproduce the front left, rear left, front right and rear right audio signals in each of the four separate speakers. The sound from the rear speakers should be of the same quality, or nearly the same quality, as the front speakers. Ideally, it is preferable to use four identical speakers.
This unit provides 10W amplification at 8 ohms for the two rear channels only.
However, it can also be used as a standard stereo amplifier, albeit with a single input.
Refurbished and in perfect working order. In excellent cosmetic condition.
Original Japanese unit operating at 100 VAC, supplied with a transformer for use with the European mains supply.
Specifications:
Total harmonic distortion: 0.
5%Damping factor:
40Input sensitivity: 100mV (line)
Signal-to-noise ratio: 90dB (line)
Output: 100mV (line), 20mV (DIN), 1V (Pre out)
Speaker load impedance: 4Ω (minimum)
Dimensions: 430 x 138 x
337mmWeight: 7.
8kgYear: 1972
