A&D GX-Z9000

Commentary

This 3-head cassette deck equipped with dbx was developed in pursuit of higher sound quality by following the design concept of the GX-93.

The recording and reproducing heads are LC-OFC wound Super GX heads.
LC-OFC (Linear Crystalline oxygen-free copper) is made by extending a crystal of oxygen-free copper into a linear shape. Compared with conventional tough pitch coppers, the number of grain boundaries with a condenser effect is reduced to about 1 / 7,500. Furthermore, copper (Cu)₂Therefore, while tough pitch copper is regarded as a combination of many capacitors and semiconductors, LC-OFC greatly improves them and significantly reduces transmission distortion. Especially for reproducing heads with minute signal current levels, resolution is greatly improved and music clearness is improved.
The core of the Super GX Head is made of ferrite, which has excellent high-frequency characteristics, and is processed with high precision using our proprietary technology. As a result, we have obtained characteristics in terms of sound quality such as low loss in the high-frequency range, wide frequency characteristics, and low distortion. In addition, we have obtained advantages such as low magnetization, excellent abrasion resistance, low dust adhesion, and low modulation noise caused by friction with the tape.

The mechanism uses a closed loop double capstan system with a dual wide tape guide.
In this system, by controlling the tape movement with two capstan and pinch rollers, disturbance from the reel can be shut out and wow flutter is reduced. In addition, by shortening the tape span, minute vibration of the tape can be suppressed. In addition, stable tape touch can be obtained with constant tape tension from the beginning to the end of winding.
In particular, our unique double-capstan system, which we have developed over many years, has obtained excellent characteristics such that the modulation noise at a frequency 2 kHz away from the signal frequency is reduced by approximately 5 dB compared single capstan.

A quartz lock DD motor is used to drive the capstan.
This motor is a direct drive motor combined with a quartz lock system. The rotation of the motor is phase-controlled based on the high-precision frequency obtained from the crystal oscillator. This reduces disturbance of rotation against all load fluctuations and provides stable rotation characteristics.

The capstan surface has undergone a unique reverse electric hard chrome plating process, which increases the tape gripping force and reduces the slip phenomenon to nearly 0, further enhancing the advantages of the double capstan system.
Moreover, this treatment method has excellent abrasion resistance, so that initial performance can be maintained for a long time.

Excellent operability and quietness are realized by installing a unique silent mechanism.

Equipped with manual bias control function.
By installing a slave bias oscillation circuit exclusively for recording bias, the recording bias value can be controlled within ± 20%.

The recording amplifier section has a non-feedback push-pull configuration and a drive system with constant current drive.
This configuration and the drive capability of the head greatly improve the linearity of the high frequency range.

The playback equalizer amplifier section is equipped with an amplifier developed based on the basic concept of simple and straight. Combined with the effect of twin active power supply, it enables high slew rate and high stability operation.

The power supply consists of separate signal system and mechanism system to prevent mutual interference between power supply circuits.
In addition, the amplifier circuit and noise reduction circuit are supplied with ± 2 independent power supplies. This allows for stable processing of the Dolby NR/dbx NR, as well as obtaining cloudless sound without interfering with the amplifier system.

A unique twin active power supply is used for the recording and playback amplifier circuit.
In order to maintain a stable power supply against current fluctuations in all bands, the twin active power supply realizes low-output impedance over a wide band, which improves response to low-frequency signals requiring a large current.

As a noise reduction system, it is equipped with Dolby B-CNR. The Dolby IC is equipped with newly developed 3-head one chip E (Encode) / D (Decode) type to reduce sound quality degradation due to characteristic error.
The GX-Z9000 is also equipped with dbx NR, which enables high-quality recording of CDs and other sources with a wide dynamic range.

In order to prevent interference from high-frequency noise components generated by the microcomputer that operates the mechanism, the regenerative equalizer amplifier is shielded with a copper-plated shield plate. In addition, measures such as the insertion of an EMI (electromagnetic interference) filter and an independent winding power transformer are taken.
In addition, an isolated spacer is used in the power transformer to prevent high frequency noise components from the power supply.

An EBET (Folded Electrode Transistor) is used from the amplifier to the power supply, which has an excellent slew rate and improved resolution.
For the film condenser, high-quality parts such as the West Germany ERO Co., which have been carefully examined in terms of sound quality, are placed in the optimum position.
LC-OFC with less transmission distortion is used for the inductor (coil) for high-frequency cutoff and high-frequency compensation to improve high-frequency resolution. The core material of this coil is a low-distortion core.
The electrolytic capacitor uses a high-purity aluminum foil vibration-proof coil structure developed exclusively for audio equipment, and the resistor uses a newly developed high-tone resistor that is carefully examined from the base material of the resistor to the coating film.

The display is equipped with a 3-way, 4-digit electronic counter that can display not only the tape counter but also the remaining time and elapsed time of the tape with high precision.
In addition, it is equipped with a 17-segment 2-color peak meter that can display within the range of -40dB to + 12 dB with a peak hold function, enabling detailed monitoring of the input level.

It is equipped with a recording level guide indicator. The indicator that indicates the allowable recording level according to the MOL of the tape is illuminated to assist the level setting.

Equipped with a REC cancel function, it rewinds to the end of the previous song with one touch, and after muting for about 4 seconds, it becomes recording standby.

Equipped with an intro-scan function, it skips the intro part of the recorded music for about 10 seconds each.

Equipped with an IPLS (Automatic Tracking) function, you can search for the introduction part of one song before or after.

Equipped with a direct lead-in and power eject mechanism, after setting the tape, it loads automatically by pressing the operation button and starts operation or standby.

The Auto Tape Selector automatically detects the type of loaded tape and sets the bias equalizer value.

It is equipped with an auto monitor function, and the monitor position is automatically switched to the source side when recording is in standby mode, and to the tape side when starting.

In order to prevent deterioration of sound quality due to vibration and resonance as much as possible, a high-strength bottom plate is adopted. In addition, a larger pedestal and a higher rigidity by double molding of vibration inhibitor are attempted.
In particular, the GX-Z9000 has a robust bottom plate to enhance the design grade and rigidity.

Equipped with an autoplay function that automatically starts playback after rewinding.

Equipped with auto-mute mechanism that can automatically create 4-second space between songs.

Uses gold-plated terminal.

Equipped with a headphone port and headphone volume.

Equipped with a timer start mechanism.

Equipped with an MPX filter that cuts the pilot signal that is mixed during air check.

The OFC connection code is included.

Power cord with polarity display is used for power cable.

Model Rating

Type	Cassette deck
Wow and flutter	0.025%WRMS ± 0.04% WPeak (EIAJ)
Frequency characteristic	20 Hz ~ 19 kHz ± 3 dB (Normal Tape) 20 Hz ~ 20 kHz ± 3 dB (Chrome Tape) 20 Hz ~ 21 kHz ± 3 dB (Metal Tape)
Distortion Factor (EIAJ)	0.5% (Metal Tape)
Signal-to-noise ratio (EIAJ)	59 dB (Metal Tape) Dolby B NR : 5 dB improvement at 1 kHz, 10 dB improvement at 5 kHz or higher Dolby C NR : 15 dB improvement at 500 Hz, 20 dB improvement at 1 kHz to 10 kHz
Dynamic range	110 dB (when using dbx NR system)
Heads	Recording : LC-OFC Super GX Head Playback : LC-OFC Super GX Head Erasing : erase heads
Motor	For capstan drive : Quartz PLL DD Motor For Reel Drive : DC Motor Cam Drive : DC Motor
Input Sensitivity / Impedance	Line : 70mV/47k Ω
Output Level / Impedance	Line : 388mV/1k Ω Headphone : 1.3 mw (8 Ω) / 82 Ω
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	20W
External dimensions	Width 475x Height 112x Depth 353 mm
Weight	7.3kg
Attachment	OFC connection code