A 3-head cassette deck equipped with a quartz lock pulse servo DD motor.
The pulse servo DD motor developed for a cassette deck based on the DD phono motor technology is carried in the mechanism part.
The basic shape of this motor is 4-phase 8-pole plane facing brushless, slotless, coreless,
FG servo, direct drive. The Hall element developed at Victor Central Research Laboratories
eliminates mechanical contacts by the brushless structure that switches the polarity, and
realizes the rotation accuracy and long life of the motor. The brushless, coreless, and
slotless structures eliminate uneven rotation and noise such as cocking.
The pulse servo DD motor employs a method of detecting the number of revolutions with
a frequency generator, and by using an all-around integral type with 204 poles and 102 pulses,
there is no detection error due to positional deviation. Furthermore, the FG magnet is coaxial
with the capstan so that the positional deviation does not occur from the beginning, and the
method of magnetizing while holding the center of the board is adopted. Moreover, the auto
balance circuit is carried in order to prevent the torque unevenness due to the temperature rise.
The DD-9 is further equipped with a quartz lock, and the rotation speed controlled by the
pulse servo is held at a constant speed rotation by the quartz lock control.
The composite material which is effective for modulation noise is adopted as a flywheel,
and the flutter component by squeal (vibration) and the turbidity of a high region are eliminated.
The all DC composition amplifier is adopted.
Since the DC configuration amplifier can reduce the number of signal system capacitors,
the distortion, noise, and phase change generated by the capacitors are reduced, and the
transient characteristics are also improved. In particular, the head amplifier is a direct
coupling using a double differential amplifier, and the microphone amplifier, recording amplifier,
and ANRS circuit are also DC configuration amplifiers with ± 2 power supplies, and all
amplifiers through which audio signals pass are DC configuration.
The combination head which used the X-cut SA head as a play head and the SA head as a
sound-recording head is adopted.
The 3-head system, which uses a recording-only head and a playback-only head, has an
optimum gap width for each head, enabling recording and playback with higher fidelity.
The SA head has a unique composite structure in which a Sen alloy chip is adhered to the
tape sliding surface of a Permalloy 6-layer laminated core at high temperature, and has
many advantages in terms of core loss, gap accuracy, wear resistance, corrosion resistance,
etc. I'm getting it. Moreover, since the maximum magnetic flux density is high, it corresponds to
the excellent high region characteristic of a metal tape.
In addition, the X-cut SA head has improved low-frequency swell (contour effect) in response
to high-frequency expansion.
The SA (Sen Alloy) erasing head is adopted as an erasing head.
The sound-recording bias, the sound-recording equalizer, and the sound-recording sensitivity
are automatically set for each tape, and the just tuning is possible for each tape.
In addition, when mounting on the DD-9 type, the direction of B, E, S for 3 heads was
examined, and the tuning time was maintained and redesigned to improve accuracy, resulting in
a more balanced recording. It's easier.
The full logic control is adopted.
ANRS and SuperANRS are carried as a noise reduction system.
It is equipped with a two-color FL level meter that can switch between peak and VU.
This level meter is a fluorescent display board with 18 segments on each side and 20 dots
on each segment, and we have devised a special idea for red color development of 0 VU or
higher.
It is equipped with a newly developed 4-digit electronic counter.
In this counter, the magnetic change of the magnet connected to the take-up reel and turns is
detected by the Hall element, counted, and displayed by FL. In addition, it is equipped with
a two-point memory mechanism, and repeat playback between any two points is possible
when used in combination with the auto-rewind mechanism.
In addition, this electronic counter can also be used as a stopwatch by switching the switch,
and the tape running time is displayed, so you can check the remaining tape time.
The electronic volume is adopted as an input volume.
This electronic volume has been changed from the conventional round knob rotary type to
the touch type by motor drive.
The timer standby mechanism is carried and the absence recording and the alarm clock play
are possible by connecting an optional timer.
It also has a timer safety lock to prevent accidental erasure.
The REC mute mechanism is carried.
The memory rewind mechanism is carried.
The playback volume linked with headphones is carried.
Equipped with a remote control terminal, it can be operated from a remote location by
connecting an optional remote control.
Model rating
Model Stereo cassette deck
head Recording: SA
Playback: X-cut
SA Erase: 2 Gap SA
motor Quartz Lock Pulse Servo DD Motor
DC Motor
Frequency characteristic Metal: 15Hz-20kHz, 25Hz-18kHz ± 3dB (-20VU recording)
25Hz-12.5kHz ± 3dB ( 0VU recording)
SN ratio ANRS off: 60dB (WTD, 1kHz, 3% THD, metal tape)
ANRS on: 5dB improvement at 1kHz, 10dB improvement at 5kHz and above
Wow and flutter 0.019% (WRMS)
External dimensions Width 450 x Height 110 x Depth 325 mm
weight 7.6kg.