![250∝W/M --0](/images/new-backgrounds/17086/1708631x1.webp)
ENGLISH
DOLBY HX PROFESSIONAL HEAD ROOM EXTENSION(DOLBY HX PRO)
1.Dolby HX PRO is a professional recording bias system which are now available in some home cassette recorders that improving dynamic range and signal clarity for
When recording audio signals which contain
The Dolby HX Pro system responds to high or low frequencies to regulate the oscilation of the bias level added to the recording head, thus providing a stable, effective bias to the audio signals being recorded.
When an audio signal contains a large number of
Bias is thus added at the optimum rate for both high and low frequencies.
2.The unit incorporates the Dolby HX Pro system which automatically adjusts the bias for nomal, CrO2, and metal tapes at both channels independently. Since the system is automatically engaged during the recording process only, the audiophile can enjoy the full benefits of any tape without worrying about proper adjustment of switches and encoding/decoding controls.
250∝W/M --0
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10
100 | 1k | 10k |
Frequency (dB)
PRINCIPLE OF DOLBY NR SYSTEM
The Dolby NR system functions so that it automatically increases recording levels of medium and high frequencies when the recording signal level is lower than the specified level (encoding), and automatically reduces the output level to the normal level during playback (decoding). In this way, the tape hiss noise is remarkably reduced without affecting the sound quality. The Dolby NR system used in your cassette deck improves S/N ratio by about 5 dB at 1kHz and about 10 dB at 10 kHz B- type and by about 20 dB on the most frequency range in
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| Dolby NR OFF |
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Response(dB) | 0 |
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| Dolby B |
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| 20 | 50 | 100 | 200 | 500 | 1000 | 2000 | 5000 | 10000 20000 |
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| Frequency (Hz) |
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