Akai GX 77BL
Akai
Japan

Tape Deck Details
Number of Motors
Number of Heads
Head Configuration
Wow & Flutter
Signal-to-Noise [dB]
Dimensions [mm]
Weight [kg]
Year built
Head Composition
Equalization
Frequency Response
Speed
3¾, 7½
Max Reel [inch]
Price
Additional Information
The Akai GX 77BL is a variant of the Akai GX-77 series, a professional-grade reel-to-reel tape deck produced in the early 1980s, widely regarded for its robust construction, advanced features, and excellent analog performance.
Technical Overview
Track System: Auto-reverse 4-track, 2-channel stereo system allowing continuous playback and recording on both tape sides.
Heads: Equipped with six heads total — 2 GX recording heads, 2 GX playback heads, and 2 erase heads. These employ advanced permalloy and ferrite/glass materials ensuring long life and consistent magnetic performance.
Tape Speeds: Supports 7½ and 3¾ inches per second (ips).
Reel Size: Designed for reels up to 7 inches in diameter.
Frequency Response:
At 7½ ips: 25 Hz to 25-33 kHz (±3 dB) depending on tape quality and conditions
At 3¾ ips: 25 Hz to 15 kHz (±3 dB)Wow and Flutter:
Less than 0.03% WRMS at 7½ ips
Less than 0.04% WRMS at 3¾ ipsSignal-to-Noise Ratio: Better than 63 dB at 7½ ips, providing a low noise floor for clean audio reproduction.
Total Harmonic Distortion: Less than 0.5% at 7½ ips.
Motors: Three DC motors—one servo DC motor for the capstan drive and two DC motors for reel drives.
Loading Mechanism: Unique tape loading roller that eases tape threading, combined with tension arms with micro-switches for automatic engagement/disengagement.
Capstan Drive: Two capstans turning in opposite directions, enabling auto-reverse with only 0.4 seconds delay.
Inputs and Outputs:
Line input: 70 mV with 47 kΩ impedance
Headphones output and line-level output: 0.775 V line out, 1.3 mW at 8 Ω for headphones
Separate left and right line input level controls and a master record level knobAdditional features:
Real-time digital tape counter with minutes and seconds display.
Three-mode timer/start switch, reverse selector, and bias adjust.
No integrated microphone input; microphone mixer optional extra (MM-77).Dimensions: Approximately 440 mm (W) x 244 mm (H) x 227 mm (D).
Weight: Around 17 kg.
Performance and Usage
The GX 77BL maintains the reliable, high-quality tape handling and sonic performance the GX-77 series is known for. Its multi-motor system ensures consistent tape tension and smooth capstan-driven speed regulation, which, combined with the advanced GX heads, offers clean, accurate analog sound reproduction. The quick auto-reverse feature is especially useful for continuous tape operation without manual rewinding.
Though it doesn’t have integrated microphone inputs, the option to add the dedicated Akai MM-77 mic mixer made it flexible for semi-professional recording. Its compact size and ease of use, coupled with robust electronics, placed it among the favored professional and high-end consumer reel decks during its production.
Summary
The Akai GX 77BL is a versatile, well-built tape deck that delivers excellent analog fidelity, mechanical precision, and practical features like swift auto-reverse and easy tape threading. It’s a solid choice for archiving, mastering, or serious home use, competing well with contemporaries like the Revox B77 or Teac models of the early 1980s.