Ampex 351 - Page 102

Specifications
Input
Input Impedance
Outputs
Gain
Distortion
Connectors
Power Input
Tubes
Dimensions
Finish
Accessories
Frequency Response
Noise
Crosstalk Rejection
Controls
Four microphone level inputs and two line high level inputs incorpo 
rating high level mixing.
Microphone; 200 ohm non-terminating; line: 100 k ohms bridging.
(With optional plug-in balance line transformer 20,000 ohms.)
Two, 1 volt normal; 30 volts maximum unbalanced to feed bridging
input of recorder.
With internal and external control settings at maximum, — 67 dbm
on any mic channel or — 27 dbm on any line channel will produce 1 volt
output. 1 volt input to the PR-10 electronics corresponds to 0 vu.
± 1 db 40 to 15,000 cycles
65 db below signal for inputs of — 55 dbm. This represents a noise
equivalent to an input signal of — 120 dbm.
At 500 cycles, less than 0.3% with — 43 dbm mic input level, Iv output
level; less than 1% with — 29 dbm mic input level, 25v output level.
65 db at 500 cycles, 50 db at 10 kc.
Four Allen-Bradley pots (calibrated step type available on special or 
der); master gain (two gang) pot; key switches for selection of mic
or line on two input positions; key switches for channel A, both or
Channel B on each mixer position; AC line switch; mixer coupling
switch (located on the back of the chassis).
Rugged “ XL ” type on all inputs and outputs except mixer coupling
strip.
105-125 volts, 50-60 cycles, 30 watts.
Six EF86 ’ s and one 12AU7
5-7/32" H, 19" L, 5-3/16" D (for 514" rack space or portable case).
Brushed stainless steel with grey knobs.
Plug-in balanced bridging line input transformer (Cat. No. 58-0116-01),
and plug-in balanced matching line input transformer (Cat. No.
58-0116-02).