Knowing the Cassette Tape
Cassette tapes are produced of a polyester type plastic celluloid with a magnetized coating. The gamma ferric oxide (Fe2O3) was the basis of the original magnetized stuff. About 1970, a doping cobalt volume procedure with a double-coating method to heighten overall tape output levels was developed and introduced by 3M company. This merchandise was commercialized as 'High Energy' under its Scotch brand of recording tapes. The tapes tagged with a 'low-noise' label are usually not that costly. However, these 'low-noise' tapes are not for high frequency reception.
Some Noted Facts
The chromium dioxide or the CrO2 was introduced by DuPont, the inventor of the particle, and the inventor of magnetic recording (which is the BASF), and then coatings using magnetic iron-ore or the Fe3O4 were developed in a try to approach the audio quality of vinyl records (like the Audua of TDK). These said developments also happened in 1970 as well. The TFK introduced Avilyn or the cobalt-absorbed iron oxide in 1974 and was demonstrated very productive. Eventually pure metal motes (as opposed to oxide formulations) were prefaced in 1979 by 3M subordinate the trade name Metafine. The tape coating on most Cassettes consist of Ferric Oxide and Cobalt mixed in varying proportions and sold today as either 'Normal' or 'Chrome' (and using various processes); there are very few cassettes on the market that use a pure (CrO2) surfacing.
Sound Quality
Simple sound recorders are designed to process with regular ferric preparations. High fidelity tape decks are commonly built with switches or detectors for the several nonparallel and leveling requirements for high performance tapes. The most common, the IEC Type I or the iron oxide tapes, use 120 µs playback equalization, while the IEC Type II or the chrome and cobalt-absorbed tapes require 70 µs playback equalization. The recording had a much farther time constant and there were differences in the 'bias' equalizations. The IEC Type III or the 'ferrichrome' or the FeCR is a dual layer tape with both ferric oxide and chrome dioxide was tested and marketed, but these were only available for a short time in the 1970's by Sony and BASF. The IEC Type IV or Metal Cassettes also use 70 µs playback equalization, and supply still further improvements in sound caliber. The quality is normally reflected in the price; Type IV usually the most expensive and Type I cassettes are generally the cheapest. BASF chrome tape used in commercially pre-recorded type I cassettes used 120 µs playback equalization to allow greater high frequency propelling rate for better audio quality, but the broader selling point for the music labels was that the same Type I cassette scale could be used for both ferric and for chrome music cassettes.
Cassette Tapes Statistics
These tapes have an average width of 0.150 inches or 3.81 millimeters. Each of its stereo tracks is 0.6 millimeters wide. Cassette tapes moves at 1 1/8 inches per seconds (or 4.76 centimeters in a tick).
