What is bias?
Bias is the amount of energy transferred to the tape. As tiny amounts of head wear begin, the tape gap grows slightly larger. It is therefore necessary to adjust so the proper amount of energy is transferred in order to maintain proper high-end response while maintained low THD. (courtesy of Nakamichi Cassette Deck FAQ)
What is level calibration?
It is the setting that assures that the level you record on tape in the record (source) mode is what comes back on play (tape) mode. Differences develop as uneven head wear occurs. Depending on use, an annual calibration is an excellent idea. (courtesy of Nakamichi Cassette Deck FAQ)
How do I clean tape heads?
To clean tape heads, use pure isopropyl alcohol and lint-free swabs. Throw the swab away after use.
How do I demagnetize tape heads?
Practical tape head demagnetizers are available for under $10. Try to find one with a plastic coated tip. If you can't find one which is plastic coated. you can slip a drinking straw or plastic tube over the tip for the same effect. This plastic will prevent the demagnetizer from scratching the head.
Before plugging in the demagnetizer, remove all tapes from your working area and unplug the recorder. Hold the demagnetizer away from the recorder as you plug it in. Slowly bring the tip of the demagnetizer up to the tape head and slide it back and forth across each tape head for five one-second strokes. Then pull it away from the head slowly and go on to the next. After demagnetizing the heads, use the tip on each metal tape guide with a similar five strokes. Last, slowly pull the demagnetizer far away from the recorder and unplug it. Recording engineers use a demagnetizer before each recording session. (courtesy of AudioFAQ)
What is a "peak limiter"?
A peak limiter sets a "never to be exceeded" plateau for sound volume; everything over this peak gets "squashed down" in volume. Used in many 70's cassette decks.
Closed-Loop Dual Capstan Transport?
A closed-loop dual capstan transport mechanism ensures smooth, precise tape traveling and as a result excellent sound reproduction.