G.R.A.S 测量麦克风|40AO|前置放大器TYPE 26CF
原装丹麦B&K 20 kHz TYPE 4958A精密阵列传声器 TYPE4958A传感器
二手丹麦B&K 前置放大器TYPE2669麦克风
现货出售 丹麦B&K 测量放大器 二手 前置放大器 TYPE2690
原装正品 B&K 丹麦 TYPE4153 仿真耳
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 G.R.A.S. 26CF can be used with all G.R.A.S. prepolarized microphones, namely:
- 1/2-inch microphones: G.R.A.S. 40AE, 40AD and 40AQ
- 1/4-inch microphones: G.R.A.S. 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 describesG.R.A.S. 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 G.R.A.S. 40AD, 40AE, 40AO and 40AQ.
Frequency range (±0.2 dB) with 18 pF microphone dummy |
Hz |
2.5 to 200 k |
Slew rate |
V/μs |
TBD |
Input impedance |
GΩ // pF |
20 // 0.4 |
Output impedance |
Ω |
< 50 |
Output Voltage Swing, min. @ 24-28 V CCP voltage supply |
Vp |
8 |
Noise (A-Weighted) max. |
μV |
2.5 |
Noise (A-Weighted) typ. |
μV |
1.8 |
Noise (Linear 20 Hz – 20 kHz) max. |
μV |
6 |
Noise (Linear 20 Hz – 20 kHz) typ. |
μV |
3.5 |
High-pass filter @3dB cut-off |
Hz |
20 |
Gain |
dB |
-0.35 |
Power supply (Constant Current Power) |
mA |
4 to 20 (typ. 4) |
DC bias voltage, typ. |
V |
14 |
Temperature range, operation |
°C / °F |
-30 to 70 / -22 to 158 |
Temperature range, storage |
°C / °F |
-40 to 85 / -40 to 185 |
Humidity range non condensing |
% RH |
0 - 95 |
Connector type |
|
BNC |
CE/RoHS compliant/WEEE registered |
|
Yes / Yes, Yes |
Weight |
g / oz |
30.0 / 1.06
|