Nine Network Australia sound recordist Charles Davey had the challenging task of recording
in the extreme environment of Mexico’s Cave of Crystals for a feature on ‘60 Minutes’.
|At the mining town of Naica in the Chihuahuan Desert of northern Mexico, the Cave of Crystals is located deep underground and has one of the harshest environments on earth. Connected to the Naica Mine nearly 1,000ft below the surface, the Cave of Crystals’ main chamber contains very large, natural selenite/gypsum crystals. The crew’s journey was extremely dangerous due to stifling 100 per cent humidity and temperatures hovering at about 48° C, which can kill a person within a few minutes..|
The project was shot on Sony XDCAM and recorded with a PDW 700 camera. For the audio Charles Davey used a Sound Devices’ 744T digital audio recorder and 442 field mixer. This kit was carried in a Petrol field bag, along with four Lectrosonics receivers, a time-code receiver and a camera link transmitting to the XDCAM. On his boom was a Sennheiser 416 and Sanken microphone heads for the four wireless mics he was using.
“The main challenge faced during this shoot was moisture and heat,” Charles said. “The gear was covered in beads of moisture within minutes of entering the cave. In no time, it became hot to the touch, and I was worried it wouldn’t operate properly.”
Another challenge was navigating the jagged cave floor to get as much footage as he could in the short amount of time he could spend in the cave. “Just moving around in general was quite difficult, as the ground was very uneven, and time was always a factor while inside the cave because we could only enter and shoot for short periods at a time,” said Charles. “The 744T and 442 audio recorder in particular faced up to the environment without dramas. There were no break downs and the audio was never compromised.”
The Sound Devices 744T, a compact four-track, file-based digital audio recorder is typically used in rigs for feature film and episodic TV sound mixing, and the time code implementation adds flexibility for various productions, from over-the-shoulder to cart-based. It records and plays back audio to and from an internal hard drive, CompactFlash cards and external FireWire drives. It can read uncompressed PCM audio at 16 or 24 bits, with sample rates between 32 and 192 kHz. Compressed audio recording and playback from 64 to 320 kbps is also supported.
The recorder’s audio path includes Sound Devices’ microphone preamplifiers made for high-bandwidth, high-bit-rate digital recording, and can help improve frequency-response linearity, low-distortion performance and low noise. The 442 field mixer that Charles used contains four microphone preamplifiers, and has now been replaced in the product line by the 552. The new model has the same attributes of the 442, plus an integrated recorder and an extra input and, again, suits small run-and-gun projects up to larger multiple-input productions. www.sounddevices.com