spaf (04/12/83)
The "half-speed" in a half speed master refers to the speed at which the album "mother" is cut. The master tape is played at half speed, and the "mother" (usually wax or shellac) is rotated at half its usual speed. Applying some of those wonderful laws of physics, it takes only 1/4 the power to cut the "mother" at 1/2 the speed. Thus, the tracks get cut much more precisely and the sound quality is better. The channel separation is much better and the fidelity is better, although an old tin box with a knitting needle won't reproduce the differences very well. I'm not sure if they're worth all that is charged for them, but I am impressed with the sound. They also wear a bit better since a higher- quality vinyl is used for the pressings.