C-Sound

The C-Sound combines the widely used AudioMoth sound recorder circuits and code with a quality hydrophone and housing from Chelonia.

Selection of gain, sampling rates 8 - 384k/s, duty cycles and frequency filtering are all available.

A full specification and instructions are available here:
https://www.openacousticdevices.info/audiomoth

The C-Sound hydrophone frequency response will be verifed by the National Physical Laboratory, London.

This hydrophone has a higher frequency range than the standard F-POD hydrophone in order to give a flatter response across the frequencies of interest.

It will share the legendary robustness of the F-POD hydrophone and uses a matched pre-amplifier to give a good frequency response.

The C-Sound produces standard WAVE files that can be analysed using many software packages, such as Audacity, which has a widely used free version, and Raven.

Chelonia does not offer any support or advice on handling the settings of the C-Sound or the data analysis, but will offer calibration as for the F-POD.

These instruments do similar things, but there is a significant difference you might not spot in the specifications:

In deployments over weeks and more in some marine locations the growth of barnacles, mussels etc aka 'biofouling' is a big issue. To remove it the simple shape and robust nature of the housing of the C-Sound makes removal much easier with no risk of damaging the hydrophone or any connections.

The HydroMoth is a very neat low-cost logger consisting of an AudioMoth in a transparent plastic case.

The sound path goes from the plastic case into the air inside which loses most of the acoustic energy due to the massive change in density. This makes it very insensitive, but for some applications at shallow depths this may be satisfactory.