As one of the loudest animals on the planet, pistol shrimp live in colonies of up to 16,000 and can snap their claws so quickly that the water around them vapourises. They also create bubbles, which implode with a loud cracking sound. The cracking noises, along with vibrant imagery of the shrimp, form the basis of a groundbreaking film.

‘The underwater world is not a silent one,’ says Ambient Recording Marketing Manager, Timo Klinge. ‘Coral reefs are filled with millions of sounds just like a jungle or a summer meadow.’

Creating a specific underwater housing (SD-UW) for the audio recorder, Ambient Recording set out to capture the sounds for first commercial documentary to feature underwater surround sound.

The German company cast Sound Devices’ 788T multitrack digital location recorder in the starring role for recording off the shore of the Caribbean island of Bonaire for a documentary entitled The Cannon Crackers of the Pistol Shrimp.

‘We knew we wanted to use Sound Devices recorders when we created our complete surround underwater rig because they are extremely compact, very rugged and have excellent sound,’ Klinge continues. ‘We created the underwater housing in order for the 788T to operate efficiently underwater.’

The Ambient Recording housing – designed to accommodate all Sound Devices 7 Series recorders – is made out of hard anodised seawater-resistant aluminium, which is then PTFE-coated, giving it the highest possible durability and stability. The top is made out of 4cm-thick Plexiglas to offer clear sight of all meters and displays. Power, record, stop and volume functions can be controlled through the housing, which is waterproof up to 100m and weighs 10kg, including the recorder – beneath the water its buoyancy is just slightly negative, which can be adjusted by additional buoyancy bodies depending on what you attach to it.

In addition to the two Sound Devices 788T recorders, Ambient Sound used a Sonar Surround RS5 underwater surround rig attached to the Sound Devices underwater 7 Series housing with four Sonar Surround DS30 directivity spheres, each equipped with an Ambient TC4042 hydrophone. Three Ambient TC 4013S hydrophones were attached to one of the camera housings and one Ambient TC4032 hydrophone was used to record distant sounds.

‘Selecting Sound Devices 7 series as the recorders to design our underwater housing around was definitely the right choice,’ Klinge adds. ‘We have tested the rig over and over and Sound Devices’ gear has consistently exceeded our expectations.’

Sound Devices 7-Series family of digital audio recorders includes the two-track (702, 702T, 722), four-track (744T) and eight-track (788T) units, which record and play audio files with either 16- or 24-bit depth at all professional sampling rates up to 192kHz (96kHz on the 788T). They support multiple storage media, and have analogue/digital I/O and high-speed computer connectivity.