MICROPHONE PREAMPLIFIER SYSTEM
Features Specs Ordering User Guide

SYSTEM SPECIFICATIONS
The following are typical and apply for 70dB gain, rms, 20Hz 20kHz, RS = 150 ohms, RL = 100k ohms, TA = 25C, AUX out option, and all outputs driven, unless otherwise noted.

Preamplifier   Outboard Gain Control
Channels balanced, symmetrical Channels, GC62      2
     Model 61 1      GC64 4
     Model 62, 62R 2 Control range 12.5 70dB
Input differential      Positions 24
     Impedance, balanced

2M ohms nom || 100pF

Control signal* 4Vdc, 78uA
          Unbalanced 1M ohms nom || 180pF Peak indicator level      +24dBu
          Phantom 13.6k ohms      Hold time 100ms
Maximum level See DR graph Dimensions 1U, 19in rackmount
Equivalent input noise See DR graph   3in (75mm) D FMS
Common-mode rejection ratio > 110dB Weight, GC62 2.0lb (0.9kg)
Frequency response 0.04dB      GC64 2.3lb (1.0kg)
Bandwidth 3Hz 200kHz
Gain range 7.5 70dB Dynamic Range
     Step 2.5dB
          Accuracy 0.1dB
          Tracking 0.1dB
     Control range (Model 61, 62) 12.5 70dB
          Positions 24
AUX input non-differential
     Impedance, balanced 2M ohms nom || 80pF
          Unbalanced 1M ohms nom || 160pF
     Maximum level +30dBu
     Equivalent input noise 111dBu
     Frequency response 0.00dB
     Bandwidth 1Hz > 300kHz 
     Gain 0dB
Crosstalk (<>all chs, 15dB gain) < 110dB
Output (A, B, AUX)
     Impedance, common-mode 6 ohms
     Maximum level (RL = 600 ohms) +30dBm The maximum input level is limited only by the maximum output level of +30dBm at or less than 0.1%THD, as the output stage clips before the input stage at all gain settings.
     Offset 0.5mVdc
Peak indicator level (Model 61, 62) +24dBu
     Hold time 100ms
Phantom supply +48Vdc, 14mA/ch Signal Path with AUX Input and Output Options
Power supply  
     Voltage options (50 60Hz) 100, 120, 240Vac
          Operating range 15%
     Power consumption, Model 61 19VA
          Model 62, 62R 29VA
     Leakage current (120Vac, 60Hz) 20uA
Dimensions 1U, 19in rackmount
     Model 61 10in (254mm) D FMS
     Model 62, 62R 14in (356mm) D FMS
Weight, Model 61      7.7lb (3.5kg) *The control link from preamp to gain control is a dc control signal (no audio) via mic cable, 2 channels per cable, XLR male to female, with all 3 pins straight-wired. The signal is mic snake compatible and noise tolerant.
     Model 62 11.3lb (5.1kg)
     Model 62R 11.0lb (5.0kg)

Features Specs Ordering User Guide
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