Manufacturers' Specifications

GRAS 12AA

Channels :
2 x Lemo 1B 7-pin microphone inputs
2 x BNC output sockets

Gain : - 20 dB :  0 :  + 20 dB :  + 40 dB and straight through

Supplies :
Preamplifier Supply : 28 V or 120 V
Polarization Voltage : 200 V or 0 V

Gain Error : < 0.2 dB

Frequency Response :
3.5 Hz to 200 kHz   ± 1.0 dB
2 Hz to 250 kHz   ± 3.0 dB

Channel Separation : > 60 dB, 20 Hz to 20 kHz

Noise Floor :
20 Hz to 20 kHz : < 0 dBA and < 4 dB Flat, with short circuit input
20 Hz to 20 kHz : < 10 dBA and < 15 dB Flat, with preamplifier. + dummy microphone

A-Weighting Filter : BS EN 60651 Type 0

Output Impedance : 30 ohms

Power Supply :
Batteries : 10 x LR6, AA type
Battery Life : 8 hours with alkaline cells
Line Adaptor : 12-18 Vdc regulated supply
Current : 190 mA with one GRas preamplifier
Fuse : 250 mA, slow, 250 V

Operating Temperature : - 10 °C to + 50 °C

Size and Weight :
Height : 132.6 mm
Width : 34.6 mm
Depth : 196.0 mm
Weight : 770 g : 1.69 lb without batteries