TEAC A-7400RX

The TEAC A-7400RX is a high-quality, semi-professional reel-to-reel tape deck produced by TEAC in the late 1970s as a variant of the A-7300RX model, designed for mastering and serious stereo recording applications.

General Design:

• The A-7400RX shares many design features with the A-7300RX but includes a quarter-track playback head, resulting in a total of four heads (erase, record, and two playback heads) for enhanced playback versatility.

• It is a two-unit system consisting of a transport section and a separate amplifier/mixer unit.

Tape and Speed:

• Supports tape speeds of 7½ ips (19 cm/s) and 15 ips (38 cm/s).

• Compatible with large reels up to 10.5 inches (Type 26 NAB reels).

Head Technology:

• Uses high-density Permaflux heads made of Permalloy, known for durability and excellent magnetic properties.

• Head configuration is stacked/inline for efficient tape contact and signal quality.

Motors and Drive:

• Features a direct-drive DC servo capstan motor for precise tape speed control.

• Two eddy current induction motors drive the supply and take-up reels, ensuring smooth tape transport.

Noise Reduction:

• Incorporates the dBx deci-linear noise reduction system, significantly improving signal-to-noise ratio and reducing tape hiss.

Performance Specifications:

• Frequency response:
  30 Hz to 28 kHz at 15 ips (±3 dB)
  30 Hz to 24 kHz at 7½ ips (±3 dB)

• Wow and flutter:
  0.04% at 15 ips
  0.06% at 7½ ips

• Signal-to-noise ratio:
  100 dB with dBx noise reduction engaged
  65 dB without noise reduction

• Stereo separation:
  80 dB with dBx
  50 dB without dBx at 1 kHz

• Total harmonic distortion:
  0.4% with dBx
  0.8% without dBx at 1 kHz, normal operating level

Inputs and Outputs:

• Four line inputs with 100 mV sensitivity and 50 kΩ impedance.

• Four microphone inputs with 0.25 mV sensitivity and 600 Ω impedance.

• Two line outputs at 0.3 V with 10 kΩ load impedance.

• Stereo headphone jack with 8 Ω impedance.

• Outputs available via XLR and RCA connectors.

Additional Features:

• Built-in 4-in, 2-out mixer with master level control and 20 dB mic attenuators.

• Dual-scale VU meters (+3 or +6 VU) for accurate level monitoring.

• Three-position bias and EQ switches for precise tape matching.

• IC logic controls with remote operation capability.

• Elapsed time counter with memory function.

• Edit button to disengage the take-up reel motor for tape splicing.

Physical Dimensions and Weight:

• Transport unit: 18½" x 18" x 11¾" (470 x 455 x 300 mm), 61.6 lbs (28 kg).

• Amplifier unit: 18½" x 8" x 12¼" (470 x 205 x 310 mm), 28.6 lbs (13 kg).

• Total system size: 37" x 16" x 24.5" (940 x 410 x 620 mm).

• Total weight: approximately 90.2 lbs (41 kg).