Denon DRM-740 Bedienungsanleitung Seite 7

ENGLISH
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DOLBY BAND C NOISE REDUCTION SYSTEM
e The Dolby noise reduction system substantially reduces the tape
background noise (hiss) inherent in the cassette medium. Dolby B NR is
most widely in use. However, Dolby C NR is a much more recent
development and represents a significantly improvements over Dolby
B NR.
e Tape background noise consists primarily of high frequency informa-
tion, which is particularly annoying during soft passages. The Dolby NR
system increase the level of low volume mid and high frequency signal
during recording and reduces the level of these signals by an identical
amount during playback. As a result, the playback signal is identical to
the original source signal, but the level of background noise generated
by the tape is greatly reduced.
DOLBY HX-PRO HEADROOM EXTENSION SYSTEM
This deck is equipped with the DOLBY HX-PRO headroom extension
system. Since the system functions automatically during recording, no
switching operation or adjustment is required. The system is effective with
any type of Normal, CrO; or Metal tapes.
The Dolby HX-PRO headroom extension system functions during recording
to lift up the saturation level in the treble range. Therefore, most of the
treble range components distorted or lost during recording on convention-
al cassette decks are more faithfully recorded on the new DRM-740 cassette
deck.
IMPORTANT INFORMATION
Condensation
The operating principle of Dolby C NR is similar to that of Dolby B NR
except for the encoding/decoding response curves. The noise reduc-
tion effect obtained with Dolby C NR is up to 20 dB, compared to 10 dB
with Dolby B NR. In addition, Dolby C NR uses an anti-saturation
network and spectral skewing circuitry, for a significant improvement in
the dynamic range of the mid- to high-frequencies.
Features of the DOLBY HX-PRO headroom extension system
(1)
(2)
(3)
(4)
Performance of Normal and CrO, tapes can be upgraded closer to that
of Metal tapes.
The dynamic range in the treble is improved significantly.
Since no decoding in playback is necessary, the improvement can be
obviously heard on any hi-fi playback system including portable
components and car systems.
The system functions whether the Dolby B/C NR is engaged or not.
e Water droplets may form on the such important parts of the deck as the rotating parts or head when the deck is used in humid places or exposed to
sudden temperature changes, such as if it is moved suddenly from a cold place to a warm place.
e The tape can be damaged or the deck may not operate if it is used under these conditions. If condensation forms, let the deck sit at room
temperature for about one hour before using it.
Cleaning the Head
e A head cleaning cassette is needed to clean the recording/playback head on this deck.
e The quality of the playback or recording sound will be poor if the head is dirty. Always keep the head clean.
* Clean the head periodically, about every 10 hours of use, in order to take full advantage of the decks performance and enjoy quality sound.
Demagnetizing the Head
e The head becomes magnetized after it are used for a long period of time or if it is exposed to magnetic forces. This results in noise and reduced
treble.
e If the head is magnetized, use a cassette-type head demagnetizer, available in stores, and demagnetize it.
TROUBLESHOOTING
Make sure of the followings before you consider as any malfunctions:
1. Are all the connections correct?
2. Is the set being operated correctly in accordance with the operating instructions?
3. Are the speakers and amplifiers functioning correctly?
If the tape deck still does not function properly, check it again, using the check list below. If the symptom does not correspond to the check list, please contact
your DENON dealer.
Tape does not run. e Power cord is off.
e Tape is completely wound up.
e Tape is loose. e Tighten tape with a pencil, etc.
e Cassette is not loaded properly. e Load cassette properly.
e Defective cassette. e Replace cassette.
Tape is not recorded when recording button is | e No cassette is loaded. e Load cassette.
pressed. e Erase prevention tab is broken off. e Cover hole with plastic tape.
Sound is warbled or distorted.
e Check power cord.
e Rewind tape.
e Heads, capstan or pinchroller are contamin- e Clean them.
ated.
e Tape is wound too tight. e Fast forward or rewind to loosen tape
winding.
e Recording input level is too high. e Adjust recording input level.
e Tape is worn out and has "drop-outs". e Replace tape.
Excessive noise e Tape is worn. e Replace tape.
e Heads, capstan or pinchroller are contamin- | e Clean them.
ated.
e Heads are magnetized. e Demagnetize heads.
e Recording input level is too low. e Adjust recording input level.
High frequency range (treble) is emphasized. e Dolby NR button is set improperly. e Set Dolby NR button properly.
High frequency range (treble) is lost. e Heads are contaminated. e Clean them.
e Tape is worn. * Replace tape.
When a CrO; or metal tape is placed in the deck, | e The cassette housing is of an older design | e Use the latest cassette with tape type detec-
a diffrent tape indicator comes on. without tape type detection holes. i tion holes.
The cassette tape cannot be removed. e If the power switch is turned off either the | e Turn the power switch ON again, and then
recording or playback mode, and the unit is press the stop ( EE ) button.
stopped, there may be case when (ele 'Then, in the stop mode, press the EJECT
cassette cannot be removed, even if the button to remove the cassette tape.
EJECT button is pressed.
SPECIFICATIONS
Type Vertical tape loading 4-track 2-channel Inputs
stereo cassette deck LINE 80 mV (-20 dBm) input level at maximum
Heads Recording & Playback (combination head) x 1 Input impedance: 50 kohm unbalanced
Erase (Double gap ferrite head) x 1 Output
Motors Capstan (DC servo motor) x 1 LINE 620 mV (0 dB) output level at maximum
Reel (DC motor) x 1 (with 47 kohm load, recorded level of
Actuator (DC motor) x 1 200 pwb/mm)
Tape Speed 4.8 cm/sec. HEADPHONE 1.2 mW output level at maximum
Fast Forward, (optimum load impedance 8 ohm
Rewind Time Approx. 100 sec. with a C-60 cassette ~ 1.2 kohm)
Recording Bias Approx. 105 kHz Accessories Parallel pin cord x 2
Overall S/N Ratio Mini-Plug Cable
(at 3% THD level) Dolby C NR on: more than 75 dB Power Supply Voltage is shown on rating label
(CCIR/ ARM) Pawer Consumption 16W
Overall Frequency Dimensions 434 (W) x 124 (H) x 275 (D) mm
Response 20 — 20,000 Hz +3 dB Weight 4.2 kg
Channel Separation
Crosstalk
Wow & Flutter
(at -20 dB, METAL tape)
more than 40 dB (at 1 kHz)
more than 65 dB (at 1 kHz)
0.03896 Wrms (JIS method), +0.1%
w. peak
* Above specifications and design are subject to change without prior notice.
Best results will be obtained with use of DENON DX and HD Series cassette tapes.
Dolby noise reduction and HX Pro headroom extension manufactured under license from Dolby Laboratories Licensing Corporation. HX Pro originated by
Bang & Olufsen.
"DOLBY", the double-D symbol [X] and "HX PRO" are trademarks of Dolby Laboratories Licensing Corporation.
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