Nakamichi BX-2

Commentary

A two head cassette deck adopting Dolby B type and C type.

The head part adopts a 2-head configuration using an RP-2D read / write head and an E-2D erase head.
The RP-2D head reduces the waviness in the low range by processing the contact surface with the tape into a hyperbolic shape.

Single capstan system is adopted for the mechanism part.
In this system, the wow is less likely to come out than in the double capstan system, but there is also a problem that the flutter is increased. In order to solve this problem, the BX-2 takes note of the effect of the rotational accuracy of the winding motor on the flutter, and adopts a metallic pulley with extremely high roundness to prevent the flutter from coming out even in the power transmission stage.

A double NF circuit is used for the recording equalizer circuit and the playback equalizer circuit in the amplifier section to reduce distortion and stabilize DC, and to compensate for head loss based on theoretical values.
In addition, a discrete configuration using a low-noise transistor compatible with the reproducing head is used for the reproduction equalizer circuit, and a low-noise operational amplifier is used for the recording equalizer circuit to obtain a dynamic range.

By making the bias current oscillator extremely stable and with very little waveform distortion, the music signal is prevented from being modulated by the instability of the bias current. In addition, there is a built-in bias adjustment mechanism for each tape position of the L and R channels, ZX, SX, and EX, so that the best bias is obtained.

The tape control mechanism uses a silent mechanism that uses a microprocessor and a dedicated motor. It is driven by a dedicated motor without using a solenoid plunger to reduce operating noise.
The BX-2 has a cam with a special shape attached to the mechanism, which detects the operating condition, outputs 3-bit digital information, and is controlled by a microcomputer.
As for the contact between the head and the tape, we reduce the damage to the tape by moving the head quickly until it comes into contact with the tape and slowly from immediately before it comes into contact.

Equipped with Dolby B Type and Dolby C Type as noise reduction system.

The front panel uses aluminum thick material that has been pulled out.
The cassette lid and meter are made of 5 mm thick acrylic glass.

Equipped with a 2-position equalizer switch, 120 μ s and 70 μ s can be selected.

Equipped with an LED peak level meter that can display from -30dB to + 5 dB.

It is equipped with a 4-digit counter using LED, and with 0000 as the base point, plus counts to 9999 and minus counts to -999.

Equipped with a recording balance volume and a recording master volume.

An MPX filter switch is mounted to prevent malfunction of the Dolby NR circuit by removing 19 kHz pilot signal included in FM radio wave.

Equipped with memory play and memory stop functions.
When the memory switch is set to the Memory Play position, the tape counter 0000 stops the playback from the fast-forward / rewind operation, and the playback starts automatically. When the memory switch is set to the Memory Stop position, the playback stops automatically at 0000 from the fast-forward / rewind operation.

It is equipped with the one touch rec pause function, and when you press the rec button, it automatically enters the recording pause state.
Then press the play button to start recording.

Equipped with Rec Mute function.

Equipped with timer recording and playback functions. By combining with an optional timer, you can record your absence or play an alarm clock.

It has an output volume.

It has a headphone port.

All the products had about 30 adjustments including bias L/R and recording / playback level L/R.

There are 2 color variations of silver and black.

Model Rating

Type	Stereo cassette deck
Truck type	4-track, 2-channel stereo system
Heads	One Record / Rehead (RP-2D) One Erase Head (E-2D)
Motor (for tape drive)	For Capstan : 1 DC servo motor For Reel : DC Motor
Tape speed	4.8cm/s
Wow and flutter	0.06% or less WTD RMS 0.11% or less WTD Peak
Frequency characteristic	20 Hz to 20 kHz (recording level -20dB)
Total S/N ratio (IHF-A, ZX Tape, 70 μ s)	Dolby B on : 62 dB or more (400 Hz, THD3%, WTD RMS) Dolby C on : 68 dB or higher (400 Hz, THD3%, WTD RMS)
Overall strain rate	1.0% or Less (400 Hz, 0 dB, ZX, EXII Tape) 1.2% or Less (400 Hz, 0 dB, SX Tape)
Erasure rate	60 dB or More (100 Hz, 0 dB)
Channel separation	36 dB or More (1 kHz, 0 dB)
Crosstalk	60 dB or More (1 kHz, 0 dB)
Bias frequency	105kHz
Input Sensitivity / Impedance	50mV/30k Ω
Output Level / Impedance (maximum output level)	Line : 0.5 V (400 Hz, 0 dB) / 2.2k Ω Headphone : 1.2 mW (400 Hz, 0 dB) / 8 Ω
Pwer	100 VAC, 50Hz/60Hz
Power consumption	Up to 23W
External dimensions	Width 430x Height 110x Depth 250 mm
Weight	Approx. 5.5 kg