Vintage Audio Recording Book booklet 4 different titles vintage sound 1950’s

Set of vintage books on tape recording and sound. Features various covers with illustrations and text. They have some shelf wear but are sound and clean internally. Tape recorders and tape recording - harold w weiler - published by radio magazines 1956 - soft cover Fundamentals of magnetic recording- audio devices inc - C J LeBel - 1951 - 46 page booklet - cover and back are there but barely attached Sound - Alexander Efron - basic science series - no 200-5 - 1957 - soft cover Tape editing and splicing - N M Haynes - robins industries corp - booklet 23 pages 1957. This group cane from the estate of a local gentleman who was chief engineer at a radio station- hosted a show- taught in local trade schools and eventually had his own radio station. I will be listing quite a few unique books over time. Thanks fir looking!