At the IAJRC-UK meeting at Reading in November 2007, there was a presentation about 'recreation' recordings that were made to take advantage of the improvements in recording methods over the years. It covered acoustic to electrical recording, electrical to hi-fi recording (largely associated with the change from recording on wax blanks to recording on tape and from 78s to LPs) and from mono recording to stereo recording. It was the latter aspect that generated the most interest especially in the attempt to identify the first genuine jazz recording in stereo. It is appreciated that there is a technical difference between stereophonic and binaural recording and reproduction but for the purpose of this article, they are both called 'stereo'.
When LP records were introduced in 1948, record companies began to reissue their 78s as compilations on the new medium. Then some companies decided to re-record the old material in high fidelity. This particularly applied to Capitol Records since it, having only been formed in 1942, did not have a back-catalogue of material. In the big band field, Capitol engaged many well-known band leaders to assmble bands to record each leader's old hits. The covers of the LPs showed a picture of the leader in black and white to represent the old lower fidelity records and then in colour to illustrate the new hi-fi versions. In fact, the LPs were generally called 'X.Y.X. in Hi-Fi'. Then stereo came on to the scene.
Stereophonic sound transmission had been demonstrated at the end of the 19th Century as part of the development of the telephone, but there was at that time no practicable means of recording and reproducing it. By the late 1920s, Alan Blumlein at EMI in England and Arthur Keller at the Bell Laboratories in the USA were independently investigating the possibilities of stereo recording and reproduction. Neither knew what the other was doing. Bell successfully demonstrated a stereo reproduction scheme using a two groove system with the grooves either on the same disc or on separate discs. Meanwhile, Blumlein went beyond this with the two sound channels within a single groove. He used two systems. The first had one channel recorded in lateral mode with the other in vertical mode. The second was with the two channels combined in what was known as 45/45 mode. Thus, he anticipated the method actually used in commercial stereophonic discs when they appeared in 1957. Blumlein also showed how to record stereophonic sound optically on motion picture sound-tracks.
Magnetic wire recording had been made practicable by Vladimir Poulson in Denmark at the end of the 19th Century and was used for many years by both amateur and a few professional recordists. The principles of magnetic tape recording were the same as those for magnetic wire recording. In Germany, during the 1930s, engineers achieved recording on tape, either paper or plastic, coated with a magnetic iron-based compound. The German engineers produced stereo tape recordings as early as 1942!
At the end of World War Two, a couple of the German machines were taken to California where they were used as the basis of the first commercial tape recorders. Bing Crosby, who wanted to be able to pre-record his radio programmes so he wouldn't need to go through two different broadcast for East Coast and West Coast time zones, provided financial support for the venture.
The recorders used tape that was a quarter of an inch wide and carried one track of recorded material; termed 'full-track'. There was an inconvenience with this in that the tape had to be rewound after being recorded or played. The next stage was the use of half-track recording so that recordings could be made in each direction and no rewinding was necessary. This paved the way for stereo recording with the two channels each recorded on one of the tracks. Unfortunately, manufacturing techniques did not allow both the half-track heads to be mounted in one housing and so two housings each with a half-track head were used, mounted some two inches apart. …