About this Stereophonic Recording
The STEREOLAB stereophonic disc represents the highest points yet reached in the recording of music on disc with so complete a fidelity to the original performance that all the consciousness of an intermediary vanishes between it and the listener, who is enveloped in the glorious sound of living music. Especially designed microphones, tape recorders and amplifiers are employed, on a basis of acoustically precise calculations, in this multi-channel recording, to produce duel master tapes each of which represents a different angle of listening. Each embodies a frequency response covering an entire range of human hearing and in combination they produce a rounded, full and balanced three dimensional sound. The disc is cut with the 45 / 45 system, making it possible to hear from a disc for the first time all of the subtle details of the original performance in proper perspective, with each instument reaching the listener from its proper location on the stage or in the ensemble. This disc may be played with any stereophonic cartridge.

In order to reproduce this disc with optimum fidelity the prime requisites are, in addition to a suitable stereophonic cartridge, a pair of preamplifiers and amplifiers of wide range and low distortion, the two speakers, preferably matched, but at least of similar characteristics. The left and right channels should be balanced so that each produces an equal volume of sound. This cannot be done by giving both the same setting as even matched speakers may vary their efficiency. The simplest way is to play a monaural containing speech or a vocal selection through the stereophonic system. (Any stereophonic cartridge will reproduce a monaural disc without damage). The right-left controls should then be adjusted until the voice appears to be coming from the exact center position between the two loudspeakers. If the volume of sound coming from left and right is equal to the ear, and yet the sound seems to be equally spread between the two speakers instead of coming out dead center, the phasing of the speakers may be out of adjustment. This can be corrected by reversing the leads of only one of the speakers. This phasing adjustment will often serve to eliminate the so called "hole in the center" effect occasionally encountered on stereo recordings when this is attributable to incorrect phasing. It should be borne into mind that both the level and phasing adjustments are purely impirical in nature.

Loudspeakers should be placed if possible about 8 to 10 feet apart (from center of left speaker cone to center of right hand speaker cone), and should preferably face straight out into the room, rather than being angled in towards center. The listener can be assured that this recording, when the playback is initially adjusted properly, will simulate to an extraordinary degree the illusion of music being performed in one of the world's great concert halls.

DUOPHONIC ULTRA-HIGH FREQUENCY DISKS are the result of a concentrated effort by a dedicated groop of world renowned artists and sound scientists, an effort which represents years of painstaking research in all phases of the recording field. In order to acheive this exciting goal of superlative quality and fidelity, each operation of the recording cycle must be supervised by qualified and dedicated personnel. DUOPHONIC ULTRA-HIGH FREQUENCY DISKS guarantee the participation of many of the world's finest musicians and technicians, the combination of musical knowledge and engineering craftsmanship that insures the production of the finest quality of musical sound.