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----- Original Message ----- From: "Jay Gaidmore" <[log in to unmask]> > Could somebody lead me in the right direction to finding out more about > reel to reel players and tapes? I am looking for information that will > help me understand the differences between 1/4 track, 1/2 track, and > full track, full-track mono, 2-track mono and stereo, 2 track-mono, full > track head and two track head. > If a reel to reel player is described as 1/4" broadcast 2-track, what > does 2-track mean, as well as 1-track, 3 track, and 4-track? In a > 4-channel, 1/4" machine, to what does the 4-channel refer? How about 2 > and 3 channel? Dunno if this has been answered...but I can answer this part: Generally, audio tape is divided into parallel "tracks" thusly: top edge of tape _____________________________________ track _____________________________________ track _____________________________________ track _____________________________________ track _____________________________________ bottom edge of tape For a momophonic (1 channel) signal, only two tracks (in some cases, 1 track) is needed. This is usually set up so the top half of the tape is recorded in one direction, then the tape is reversed and the bottom half is recorded in the opposite direction. This doubles the playing time of a given length of tape. For a stereophonic tape (see diagram above) two tracks are laid down in each direction, since there are two channels each with a different signal. Cassettes also use this system...since cassette tape is 1/8" wide, each track is 1/16" wide. An "8-track" cartridge has exactly that many tracks; since the stereo signal requires two tracks, four different pairs of tracks are available, and the playing heads shift slightly for each pass of the continuous-loop tape to play each of the four segments of the recorded material. Professional machines, using wider tape (up to at least 2") can record many more separate tracks (or pairs of tracks for stereo)... up to at least 64 tracks (32 pairs). Usually, these are recorded in such a way that playing all the tracks simultaneously would result in the recorded song(s) being played; the "mix" refers to selecting the levels for each of the 32 stereo signals so the final combination sounds as the engineer desires it to (each instrument or vocal usually is recorded to a different channel or pair of tracks). The engineer, of course, has to keep track of which signal is on which channel, so he/she/it knows which knob to turn to raise or lower the lavel of, say, the bass guitar. However, it is possible, by some judicious fiddling with knobs, to put entirely separate mono signals on a pair of stereo tracks using a home-use reel-to-reel tape recorder. I have a number of reel-to-reel tapes done this way of items from my 78 collection; turn the level on one channel to zero while taping 78's on the other channel for the first and second passes (one each direction) and then feed the input into the unused channel for the third and fourth passes. Note that it is possible to record an odd number of tracks...but not very useful (except for one track, which is how the earliest tape machines worked). You could either design heads of a special width to record one third (or 1/5 or 1/7, etc.) of the tape, or use an even number of tracks and not record one. However, this means you would get an odd number of playing passes, so the tape would at the end have to be rewound without playing, so it would be ready for playing later. > I have seen many references to setting the correct azimuth. What is > this and how do you set it correctly? This one I can't answer! > As you can see I am very much a novice trying to learn. References to > website or publications that would help answer the questions above would > be greatly appreciated. Hope the above helps... Steven C. Barr