UltraSoundGate Charge Amplifier with Hi-Pass Filter

for passive hydrophones without integrated pre-amplifier

part # 42002 (USG), 42003 (P48)

This charge amplifier is available in two versions that allows to connect passive hydrophones either to the UltraSoundGate units (#42002) or to other recording equipment that supplies 48V phantom-power (#42003).

  • Hydrophone input connector : female BNC socket
  • Output connector : male XLR-5 (USG version) or XLR-3 (P48 version) socket
  • Selectable input resistance : 3.3 kOhm … 15 MOhm
  • Selectable input capacitance : 100 pF or 1 nF
  • Available hi-pass cut-off frequencies at an input capacitance of 1nF [Hz] : 10, 25, 50, 100, 250, 500, 1k, 2.5k, 5k, 10k, 25k, 50kHz (or 100 Hz … 500 kHz at 100 pF)
  • Gain = 20 log (capacitance of the hydrophone / selected input capacitance)
  • Physical dimensions : 85 x 25 x 48 mm
  • Weight : 90 g

The gain of the charge amplifier depends both on the nominal capacitance of the connected hydrophone and the selected amplifier input capacitance. A hydrophone capacitance of 3nF and an input capacitance of 1nF would provide a gain of approximately 10 dB. The alternate input capacitance of 100pF would provide a gain of 30 dB. The supply voltage for the amplifier is provided by the UltraSoundGate device (via USB), which means that there is no additional power supply required. A special phantom-powered version allows to connect the amplifier directly to other audio recording equipment. 

Compatible hydrophones are for instance RESON TC4013RESON TC4033 or RESON TC4034.