Category:Mid High Fidelity
Country of Manufacture:Japan
Release dates:1962 - 1965
Speeds: 1 7/8, 3 3/4, 7 1/2
Max Reel Size("): 7"
Number of heads: 3
Dimension: 15½ x 11 x 17" (394 x 279 x 432 mm)
Head Composition: Permalloy
Head Configuration: Stereo
# Motors: 1
Frequency Response:(all 3 dB): 7½ ips: 50Hz - 15kHz
Wow and Flutter:7(RMS): 0.15% at 7½ ips. 0.23% at 3¾ ips & 0.35% at 1 ips
Signal-to-Noise Ratio:better than 55dB each channel
Sound quality rating:5 / 10
Long-term reliability rating: 5 / 10
Weight: 43 lbs(19.5 kg)
The RS772 was the largest and most comprehensive of the 1962 National range – a quarter-track stereo machine with three heads and twin speakers.
Reel sizes up to 7″ were accommodated with three playing speeds (up to 7½ ips).
At the front of the machine were twin volume and tone controls, and a master playback control incorporating the On/Off switch. The six black piano keys from left to right are: rewind, stop, fast forward, playback, record and pause. two speakers were provided, one 8 x 5 inch internal for the left channel and a 7″ circular speaker
in the lid for the right channel.
Cross talk rejection: better than 55dB / Harmonic distortion: less than 1.8% at 3dB below rated output / Valve complement: 2 x 6267 (EF86), 2 x 12AX7, 3 x 16A8, 2 x OA70 diodes & a selenium rectifier / Rewind speed: within 3 minutes for 1,200 ft reel / Audio output power: 5 watts per channel / Inputs: 2 low impedance 20k (unbalanced) mic inputs, high impedance 100k (unbalanced) inputs / Outputs: 2 extension speakers (8 ohm), 2 line outs 2.2k (unbalanced) cathode followers / Speaker(s): 8 x 5″ for left channel, 7″ round for right (in lid)