CCP Preamplifier with BNC Connector GRAS 26CF 1/2″

Gain and filter switch settings

There are two flush-mounted switches for selecting various combinations of gain and filtering, i.e.:

Gain switch settings:

• 0 dB – for normal microphone signals.
• +20 dB – for boosting weak microphone signals.

Filter switch settings:

• A-Weighting – as required in standard measurements.Linear – to let the microphone signal passunfiltered.
• High-pass – to cut off unwanted low frequencies.

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.

The GRAS 26CF can be used with all GRAS prepolarized microphones, namely:

• 1/2-inch microphones: GRAS 40AE, 40AD and 40AQ
• 1/4-inch microphones: GRAS 40BE and 40BD, using the optional 1/2-inch to 1/4-inch adaptor RA0019
• It has an integrated BNC output connector.
• The casing is made of stainless steel for maximumstrength and durability.
• CCP stands for “Constant Current Power” and describesGRAS power supplies that maintain a constant level ofcurrent for driving IEPE transducers like this preamplifier which can be used with prepolarized microphone cartridges such as GRAS 40AD, 40AE, 40AO and 40AQ.