Fairchild Recording Equipment, LLC Fairchild 670

INPUT AND OUTPUT IMPEDANCE: 600 Ω
RANGE OF INPUT LEVEL: 0 dBm to +16 dBm
OUTPUT LEVEL: +4 or +8 dBVU (+27 dBm clipping point)
GAIN: +7dB
FREQUENCY RESPONSE: 40 cycles to 15 kc +/- 1dB
NOISE LEVEL: 70 dB below +4 dBm
LIMITING NOISES: Below audibility
INTERMODULATION DISTORTION: Less than 1% at any level up to + 18 dBm output (no limiting) Less than 1% at dBm limiting +12dBm output
TIME CONSTANT ATTACK AND RELEASE TIMES:
(Note: Positions 5 and 6 release times are automatic function of program material)
Position 1) .2 ms / .3 sec
Position 2) .2 ms / .8 sec
Position 3) .4 ms / 2 sec
Position 4) .4 ms / 5 sec
Position 5) .4 ms / .2 sec individual peaks, 10 sec multiple peaks
Position 6) .2 ms / .3 sec individual peaks, 10 sec multiple peaks, 25 sec consistently high program levels.
COMPRESSION RATIO: A function of the amount of limiting as well as setting of the two threshold controls which can be set to operate at ratios from 1:2 to 1:30
POWER REQUIREMENTS: 120 or 240 volts, 60 cycles AC, 3 amps.
CONTROLS:
a) 2 Input Gain controls: Step attenuator: 1 dB per step.
b) 2 Threshold Controls: continuously variable.
c) 2 Time Constant Switches: 6 positions so as to provide fixed and variable time constants for any type of program material.
d) 2 Metering Switches: 3 positions so as to measure plate current of each control tube, or as a limiting indicator.
e) Mode Switch: A-B positions: 2 independent limiters. Vertical-Lateral position: matrixing input and output, left and right in and out, limiting action vertical-lateral.
f) On-off switch

Installed Tubes: 8x 6386, 2x 12AX7, 4x 6973, 2x 12BH7, 1x E80F or (1x EF806), 1x 5651, 1x EL34, 1x GZ34