Nakamichi 482Z

Commentary

This is the second generation cassette deck of the 480 series equipped with Dolby C Type NR, bias fine adjustment mechanism and LED peak level meter.

As a noise reduction system, Dolby B type and C type are mounted.
The Dolby Dolby C-type is basically the same as that of the B-type. The Dolby C-type amplifies and records only the low level signal in the middle and high range of which hissing is a concern from the viewpoint of audibility, and returns it to the original level at the time of playback, thereby eliminating the hissing attached to the tape. The C-type is an extension of this, and achieves a total noise reduction of up to 20 dB by receiving 10 dB each from two noise reduction processors for the high-level stage and low-level stage.
Type C uses a sliding band method that varies the starting saturation according to the input level and frequency components to suppress the bleeding phenomenon. In addition, the spectral skewing circuit suppresses the recording saturation of high-frequency signals of 8 kHz or higher to prevent the degradation of autumn KARAS h-number characteristics and the modulation of low-frequency signals. The anti-frequency network circuit also suppresses the recording saturation caused by large instantaneous inputs.

The 482Z uses a dedicated Dolby NR processor for both recording and playback. Combined with a discrete three head configuration, simultaneous recording and playback monitoring is possible.

The head part uses a discrete three head system in which three heads for recording, reproduction, and erasing are completely separated from each other in structure.
The advantage of this method is that you can precisely adjust the verticality (azimuth) of the gap between the recording and reproducing heads. On the 482Z, you place the reproducing and recording heads in the center window of the cassette, and the erasing head in the left side small window. Both heads are located between the double capstan, ensuring a constant tape tension and head-touch without spacing loss.

A P-8L-type playhead is used as the playhead.
This head uses a laminated core made of crystalline material and has a narrow gap of 0.6 microns to prevent loss during playback and obtain wide frequency characteristics. In addition, it is designed to eliminate low-frequency waviness (contour effect) to enable flat playback down to the ultra-low frequency range.
In addition, it adopts a special shape that eliminates the phenomenon of unbalanced core and realizes a long life of more than 10,000 hours.

The recording head uses an R-8L catalogue sound head.
The 3.5 micron gap head uses a laminated core of crystalloid as well as a read head, and provides high coercivity, sharp critical zones when high-density tapes are used, and high MOL (maximum output level) recording from low to high frequency with no magnetostriction or saturation even when a large bias current is applied.
As with the reproducing head, the life of the head is over 10,000 hours.

E-8L-type erase head is used for the erase head.
This head is a double-gap type that uses a ferrite core with excellent high-frequency characteristics and a Sendust core with high magnetic flux density at the tip.

The mechanism uses a frequency distributed double capstan system.
In this system, stable tape running and head touch are obtained by the double capstan system. Moreover, by changing the diameters of the two capstan and the flywheel, overlapping of flutter cycle is avoided, and overall wow and flutter characteristics are improved.
In addition, it is equipped with a tape pad lifter to prevent adverse effects due to uneven pad pressure.

A DC servo motor is used as the main motor.
This motor detects rotational speed rotational speed as a change in voltage and controls the rotational speed to an accurate value.

A resonance damping type chassis is used for the chassis. Aluminum alloy, which has a larger damping characteristic than iron, is used, and resin is outsold to absorb microvibrations harmful to sound and prevent resonance.

C-MOS logic control is adopted for the operation system.
In this system, when the self-locking control button is pressed, the control circuit is activated and motor commands are issued to drive the mechanism. By using a cam driven by a motor instead of a solenoid plunger, sound at the time of operation is reduced. Damage to tape and transport is reduced by soft tape touch. In addition, temperature rise and power consumption are reduced.

Logic control type soft touch button is used for the control part.
It also simplifies operations and improves reliability by allowing you to move directly from rewind or fast forward to regenerating condition without having to go through the stop button.

Equipped with a bias fine tuning mechanism.
This is in consideration of the slight difference in the optimum bias value even for tapes at the same position. With the 482Z, while monitoring playback sound during simultaneous recording and playback, the monitor switch is switched to Source/Tape so that there is no difference in sound quality.
The variable range of the bias current is ± 10% from the center click position.

Equipped with a wide-range LED peak level meter for level display during recording and playback, it can display 50 dB of -40dB to + 10 dB in 16 segments.

Equipped with a timer recording and playback mechanism. By using a general audio timer, it is possible to record your absence and play an alarm clock.

Built-in MPX filter.

Equipped with a high-output headphone port.
In addition, it is equipped with a 2-level switch for headphone amplifier.

Equipped with a tape start memory function.

Remote Control Unit RM-100 (sold separately) can be used.

Model Rating

Type	Cassette deck
Truck type	4-track, 2-channel stereo system
Heads	3 heads (1 erase, 1 record, 1 play)
Motor (for tape drive)	For Capstan : 1 DC servo motor For Reel : 1 DC Motor
Tape speed	4.8 cm / sec
Wow and flutter	0.06% or less Wrms 0.11% or less Wpeak
Frequency characteristic	20 Hz to 20 kHz
Overall S/N ratio (70 μ s, ZX Tape)	Dolby B NR in : 63 dB or more (400 Hz, 3% THD, IHF-A wtd rms) Dolby C NR in : 69 dB or more (400 Hz, 3% THD, IHF-A wtd rms)
Total Distortion Factor (400 Hz, 0 dB)	0.9% or Less (ZX Tape) 1.0% or Less (SX, EX II 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	50mV/30k Ω
Output (400 Hz, 0 dB)	Line : 600mV/2.2 Ω Headphone : 10 mw (Phones Level : High) / 8 ohm
Pwer	100 V, 50/60Hz
Power consumption	30W max.
External dimensions	Width 450x Height 135x Depth 289 mm
Weight	Approx. 6.4 kg
Sold Separately	Remote Control Unit RM-100 (¥ 6,000)