This sub-bottom profiler is EdgeTech's long running success story in providing Full Spectrum (“chirp”) imaging. Under any conditions when compared to other sub-bottom profilers, the SB-512i provides better images more deployment options, and interface flexibility. The SB-512i has a frequency range from 500 Hz to 12 kHz. This system uses special design transmitters with low Q widesband characteristics best suited for “chirp” transmissions. If conventional off-the-shelf transducers are used then there is a need to compensate in software for the narrow band characteristics of the transmitters. The result is visible in the images created. At least two hydrophones are installed in the tow vehicle to reduce acoustic scattering from the sides. This results in a narrower across track beam pattern. Preserved in the output of the Full Spectrum chirp processing in the signal phase.