Akai GX-600DB: The Pinnacle of Dual-Transport Cassette Engineering

The Akai GX-600DB came out in 1978. It is a dual-transport cassette deck, built with broadcast-quality performance in mind, and the twin transports allow duplication, monitoring, and editing. It is not as widely recognized as the decks from Nakamichi or Revox, but it remains a cult favorite among tape enthusiasts.

Historical Context: Akai’s Legacy in Analog Tape

Akai, a Japanese electronics company founded in 1946, became known for high-quality reel-to-reel recorders in the 1960s and 1970s. As the cassette format matured in the late 1970s, Akai moved its engineering expertise to compact tape systems and built a line of high-fidelity cassette decks under the GX series. The GX-600DB was one of the most ambitious models in that lineup. It was designed for semi-professional use in studios, radio stations, and mastering environments, not just for home listening.

The "DB" in GX-600DB stands for Dual Base. It refers to the twin transport mechanisms housed in a single chassis. You could play one tape while recording onto another, or dub between cassettes with minimal generational loss. That made it useful for archivists, educators, and musicians before the digital era.

Technical Specifications

Feature	Specification
Year Introduced	1978
Transport Type	Dual independent cassette transports
Tape Speed	1⅞ ips (4.76 cm/s)
Head Configuration	Separate record/play heads per transport
Erase Method	AC erase
Frequency Response	30Hz – 18kHz (with CrO₂ tape)
Wow and Flutter	< 0.06% (WRMS)
Signal-to-Noise Ratio	66 dB (Dolby B), 72 dB (Dolby C)
Total Harmonic Distortion	< 1.5%
Input/Output	Line in/out (RCA), mic in (¼"), headphone out
Tape Types Supported	Type I (Normal), Type II (CrO₂)
Dolby Noise Reduction	Dolby B and C (switchable per deck)
Motor System	Dual direct-drive capstans
Display	Dual VU meters, tape type indicators
Dimensions	480 mm × 175 mm × 420 mm (W×H×D)
Weight	16.5 kg (36.4 lbs)

Sound Characteristics and Performance

The Akai GX-600DB was engineered for accuracy and transparency. It has separate record and playback heads for each transport, so it avoids the compromises of combined heads and gives a cleaner, more detailed sound. The ferrite playback heads give excellent high-frequency response and durability. The tape path uses rubber pinch rollers and metal guides to minimize tape wobble and azimuth errors.

Sonically, the GX-600DB is balanced and neutral. Bass is tight and well-controlled, mids are clear without harshness, and highs extend smoothly with minimal sibilance. With CrO₂ tapes and Dolby C noise reduction, the deck reaches a signal-to-noise ratio that rivals many reel-to-reel systems of the era.

One of its standout qualities is dynamic range and transient response, which matter for capturing live music or spoken word. The dual VU meters give accurate level monitoring. The direct-drive capstan motors hold tape speed steady, which means low wow and flutter and excellent pitch stability.

Notable Features and Innovations

The dual-transport design was the defining feature of the GX-600DB, but several other innovations set it apart:

Independent Deck Control: Each transport can be operated separately, with full record, play, pause, and stop functions. This allows for real-time monitoring of a source tape while recording a copy.
Dolby B and C Compatibility: Offering both noise reduction systems gave users flexibility—Dolby B for casual listening, Dolby C for high-fidelity duplication.
Professional Connectivity: Line-level RCA inputs/outputs, a ¼" microphone input, and a dedicated headphone amplifier made it suitable for field recording, broadcasting, and studio use.
Tape Type Selector: Manual switches for Type I and Type II tapes allowed optimal bias and equalization settings, maximizing fidelity.
Robust Build Quality: Housed in a heavy-gauge steel chassis with a brushed aluminum front panel, the GX-600DB was built to endure daily use in demanding environments.

The front panel is clean and functional, with large transport buttons, clearly labeled switches, and dual VU meters. The transport controls feel solid, precise, and tactile.

Common Issues and Maintenance

Like all vintage tape decks, the Akai GX-600DB needs periodic maintenance to perform at its best. Common issues include:

Deteriorated Rubber Components: Pinch rollers and drive belts can harden or crack over time. Replacement with modern equivalents is essential for proper tape tension and speed accuracy.
Dirty or Worn Heads: Playback and record heads should be cleaned with isopropyl alcohol and demagnetized regularly. Over time, heads may wear and require replacement or resurfacing.
Capstan Bearing Dryness: The direct-drive capstans rely on lubricated bearings, which can dry out, leading to speed instability.
Switch and Potentiometer Noise: Dust and oxidation in volume controls or mode switches can cause crackling. Contact cleaner can help, but severe cases may require component replacement.

With two transports, the GX-600DB has more moving parts than a standard deck, so servicing is more complex. Its modular construction does make repairs more manageable for experienced technicians.

Current Market Value and Collectibility

The Akai GX-600DB is a rare find today. It is not as widely collected as the Nakamichi 580 or Sony TC-800B, but it has a loyal following among cassette purists and analog archivists. In working condition, with both transports functional and properly aligned, it typically sells for $400-$700, depending on cosmetic condition and included accessories.

Fully restored units with replaced belts, cleaned heads, and calibrated electronics command higher prices, especially with original manuals or packaging. The dual-deck functionality makes it particularly desirable for people digitizing cassette collections or making high-quality tape dubs.

Collectibility is helped by its low production numbers and professional pedigree. Unlike mass-market cassette decks, the GX-600DB was a niche product.

Conclusion: A Forgotten Gem of Analog Engineering

The Akai GX-600DB is more than just a cassette deck—it’s a symbol of a time when analog technology reached its peak. Its dual-transport design, professional-grade components, and meticulous build quality reflect Akai’s dedication to audio excellence. While overshadowed by flashier competitors, the GX-600DB delivers performance that stands the test of time.

For the modern audiophile, it offers a tangible connection to the analog past—a machine that rewards care and attention with warm, detailed sound and the satisfying mechanics of tape in motion. Whether used for music, archiving, or simply as a centerpiece of a vintage setup, the GX-600DB remains a remarkable achievement in cassette deck engineering.

If you find one in good condition, it is a purchase worth making.