Cassette Decks Glossary
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2-head and 3-head cassette decks
With 2-head cassette decks, one head is a combination play/record head and the other is an erase head. 3-head decks use separate heads for play, record, and erase, so you can monitor directly off the tape while recording from another source.
Automatic bias adjustment
With the touch of a button, the cassette deck automatically records a series of test tones, determines the proper bias setting to optimize recording quality with the tape you're using, then rewinds the tape so you're ready to record.
Plays (and records on some models) both sides of a tape without you having to take it out and flip it over. Because the mechanism can change directions, you can switch sides anytime with the touch of a button. Auto-reverse is handy for uninterrupted playback of an entire tape (or two entire tapes in a dual-well auto-reverse deck with relay play). The auto-reverse recording feature is especially useful if you need to do unattended recording of long performances.
An inaudible high-frequency tone (typically around 100 kHz) that is mixed with the input signal and passed through the recording head to excite the tape particles, preparing them to record effectively.
Each tape formulation requires a particular bias level to maximize its recording response. If too much bias is used, high-frequency response will be impaired, causing the recording to sound dull. If too little is used, high frequencies will be accentuated, causing the recording to sound overly bright and harsh. In addition, distortion will increase and the amount of signal the tape can accept at middle frequencies will decline.
Some decks automatically optimize recording bias for whatever tape you're using. This is more convenient than decks that let you make manual adjustments, but some audiophiles prefer the greater flexibility of a deck that lets you adjust the bias yourself.
Automatically zips past unrecorded sections of tape.
Dolby® HX Pro
This circuit adjusts cassette tape bias during recording to extend dynamic headroom and improve the tape deck's ability to record high frequencies without distortion.
Unlike Dolby noise reduction systems, Dolby HX Pro requires no decoding. That means if you record a cassette with an HX Pro home deck, you'll enjoy the full benefits of its treble extension when you play the tape back in any car stereo or portable cassette player.
Dolby noise reduction
Dolby noise reduction systems reduce cassette tape hiss and background noise. Dolby B reduces high-frequency hiss by 8 to 10 dB. Dolby C works over a wider frequency range and reduces hiss by 15 to 18 dB.
Dolby S covers the full range of audible frequencies, reducing hiss up to 24 dB in the higher frequencies, and up to 10 dB in the lower frequencies. Dolby S noise reduction is the most effective at increasing the signal-to-noise ratio of the deck.
Dolby noise reduction is an "encode/decode" process — both the recording deck and playback deck must have the same type of noise reduction (B, C, etc.) for best results. A partial exception to this rule is Dolby S, which was specially designed to also provide good sound when played back on any deck with Dolby B, including portables and car decks.
The portion of the audible frequency range (20-20,000 Hz) a deck can reproduce. Several values may be shown: one for standard (type I) tape, one for high-bias (CrO2) tape, and one for metal tape (where applicable).
Dual-well decks with this feature allow you to make good quality recordings at twice the normal speed when dubbing from one tape to another.
Lets you plug in a microphone to make live recordings.
Multiplex (MPX) filter
All FM stereo broadcasts contain a 19 kHz pilot tone that tells the receiver to decode stereo. This tone can interfere with the operation of a cassette deck's Dolby noise reduction circuits. An MPX filter removes the pilot tone for better recording. Switchable MPX filters allow for higher frequency recordings with sources other than FM.
Allows you to increase or decrease the speed of playback in order to raise or lower the music's pitch.
A dubbing deck feature which automatically begins playing the second tape when the first tape is finished. You can play up to four sides non-stop.
A dual-record dubbing deck feature which automatically begins recording onto the second tape when the first tape is finished. You can record up to four sides non-stop.
A measure of how well a cassette deck silences background noise. A higher rating — in decibels (dB) — indicates less noise.
An especially useful feature when recording, it gives you an estimate (in minutes and seconds) of how far into a tape you are.
Wow and flutter
Measures the variance in a cassette deck's playback speed. The lower the percentage, the better the performance.