G.R.A.S. Sound & Vibration A/S products

The GRAS 1/2" Preamplifier 26CA-HT is similar to the GRAS 26CA Standard Preamplifier, but optimzed for use in high-temperature applications up to 120 °C (248 °F). It uses a CCP (Constant Current Power) supply, e.g. GRAS 12AL 1-Channel CCP Power Module with A-weighting filter. It has a very low inherent noise level, a large dynamic range and a frequency response from below 2 Hz to above 200 kHz. Its small ceramic thick-film substrate has a very high input impedance, and is shielded by a guard ring to minimise the influence of stray capacitance and microphonic interference. It has TEDS* according to IEEE P1451.4 for easy self identification and reading of calibration data. It has an integrated BNC output connector and can be used with all GRAS prepolarized microphones. The casing is made of stainless steel for maximum strength and durability.

GRAS26AI is a preamplifier designed for low-frequency applications in the laboratory and field and accommodates directly for all IEC 61094 standardized 1/2" externally polarized measurement microphones. It is rugged and reliable and can handle microphone signals up to 50 Vpeak within 1 Hz to 200 kHz. The printed circuit board is made by use of thick-film substrate technology and optimized with respect to maximum suppression of microphonics and moisture rejection. The high-quality, standard 7-pin LEMO male connector is integrated into the preamplifier and ensures that only one type of connector and cable is required for both connection and extension. 26AI is factory calibrated individually and delivered with a calibration chart stating its A-weighted and linear self-noise.