In addition to the simple configuration of 2 heads and a single capstan, the basic cassette
deck has the minimum necessary functions.
It is made in pursuit of total balance for the sound because it is simplified.
In the recording / playback head, the effective gap width of the head is set to 1.2 microns,
which is the playback limit of 20 kHz, so that the characteristics of recording and playback
are optimally balanced, and the core material has a high saturation magnetic flux density
of 10,000 gauss. I am using the sentust that I have.
At Nakamichi, we carry out strict and meticulous manufacturing control, such as processing
the core material without applying stress at all, and applying special treatment to prevent
distortion after each process, and keep the linearity of the gap severe. By doing so, we
have acquired the playback ability to clear 20kHz.
Moreover, the contour effect is suppressed to the minimum by adopting the original
hyperbolic (hyperbolic) shape, and the swell of a low region is reduced.
The double gap type which used ferrite which was excellent in a high frequency characteristic
as a core material is adopted as an erasing head.
A high erasing rate is ensured even with metal tapes that have low high-frequency loss,
coercive force, and high residual magnetic flux density.
The amplifier section has a completely symmetrical design for the pattern and circuit
configuration of the L / R printed circuit board, and consideration has been given to balancing
the characteristics of the parts and aligning the length of the signal shielded wire with
the L / R.
In addition, we have made adjustments over 30 items in the manufacturing process for every
unit to improve total quality.
In the sound-recording amplifier part, since the characteristic of a head is good, the amount
of compensation can be reduced, and as a result, a sufficient margin is secured and the
flat frequency characteristic is maintained.
Moreover, the low distortion is aimed at, and the double NF circuit which aimed at
the improvement of DC stability is adopted while suppressing the generation of distortion
by a capacitor by having the NF loop for each DC component and AC component separately.
Furthermore, the
high-through-rate low-noise operational amplifier is adopted as an amplification stage, and
the distortion is reduced.
The double NF circuit is carried in the play amplifier part as well as the sound-recording
amplifier part, and the constant distortion and the improvement of DC stability are aimed
at.
In the mechanism section, the most important point in designing the transport mechanism
is the removal of "flutter".
In the BX-125, since the rotation accuracy of the take-up reel motor is greatly related to the
flutter in the single capstan method, a high-performance motor is adopted and the pulley is
made of metal with high roundness for power transmission. It prevents the generation of
flutter.
Moreover, the vibration by rattling is eliminated by fixing the cassette firmly in the
reference position.
Nakamichi's original silent mechanism is adopted.
This is a method in which a dedicated microprocessor-controlled motor drives the operation
control cam of the head base and brakes without using any plunger to drive the mechanism,
and all operations can be started quickly with a light touch of the operation button.
In particular, the start-up of the Play operation moves speedily until just before the head
touches the tape, and when it touches, it slows down to a two-speed type to suppress damage
to the tape.
The double speed master fader control which can choose a two-step fade-in / fade-out for
4 seconds and 2 seconds is carried.
Auto repeat function, Dolby B / C type NR system, wide scale LED peak level meter, MPX
filter, memory stop, timer REC / play function, L / R independent recording level control,
output volume, 3-position tape selector, equalizer selector , Headphone jack, one-touch
REC pose, and many other functions.
RP-2G recording re-combined head E-2D Erase Head
Model rating
Model Stereo cassette deck
head 2 heads (erasing x1, recording / replaying x1)
motor <Tape transport>
For capstan drive: DC servo motor
For reel drive: DC motor
<Mechanism>
For cam drive: DC motor
Wow and flutter 0.06% or less WTD RMS
± 0.11% or less WTD Peak
Frequency characteristic 20Hz-20kHz (recording level -20dB)
Total S / N ratio (70μs, ZX tape, 400Hz, 3% THD,
IHF A-WTD RMS) Dolby C type NR on: 68 dB or more
Dolby B type NR on: 62 dB or more
Total distortion (400Hz, 0dB) ZX, EXII tape: 1.0% or less
SX tape: 1.2% or less
Input sensitivity / impedance 50mV / 30kΩ
Output level / impedance
(400Hz, 0dB, maximum output level) Line: 0.5V / 2.2kΩ
Headphone: 2.2mV / 8Ω
Power supply AC100V, 50Hz / 60Hz
power consumption Up to 17W
External dimensions Width 430 x Height 100 x Depth 250 mm
weight About 5kg.