Sound Devices Keeps its Cool in Mexico’s Cave Of Crystals

When Nine Network Australia sound recordist Charles Davey was given the task of recording audio in the extreme environment of Mexico’s Cave of Crystals for a feature story on the Nine Network Australia news program 60 Minutes, he turned to Sound Devices’ 744T digital audio recorder and 442 field mixer.

Located in the mining town of Naica in the middle of Northern Mexico’s Chihuahuan Desert, the Cave of Crystals is situated deep underground and features one of the harshest environments on earth. Connected to the Naica Mine, which is nearly 1,000 feet below the surface, the Cave of Crystals’ main chamber contains giant selenite/gypsum crystals – some of the largest natural crystals ever found.

For this perilous journey, Davey and his Sound Devices gear descended into the heart of the mine, where furnace-like heat and searing humidity can kill a person. “The main challenge faced during this shoot was moisture and heat,” Davey explained. “With stifling 100-percent humidity and temperatures hovering around 118 degrees Fahrenheit (48 degrees Celsius), this meant the Sound Devices gear was basically covered in beads of moisture within minutes of entering the cave. In no time, the gear became hot to the touch, and I was worried it would not operate properly.”

Another challenge Davey faced 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 for short periods at a time,” Davey added. “Temperatures were hot and the humidity was ridiculous, but the Sound Devices gear never gave up. The 744T and 442 faced up to the environment without any real dramas. There were no break downs and the audio was never compromised.”

Sound Devices’ 744T, a four-track, file-based digital audio recorder, has become a staple in the rigs of many feature film and episodic television sound mixers. The super-compact 744T records and plays back audio to and from its internal hard drive, CompactFlash cards and external FireWire drives, making field recording simple and fast. The 744T reads 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 time code implementation makes the 744T ready for any recording job, from over-the-shoulder to cart-based production. The 744T also includes Sound Devices’ next-generation microphone preamplifiers, which are designed specifically for high-bandwidth, high-bit-rate digital recording.

Sound Devices’ 442 field mixer, which has been replaced in the product line by the 552, contains four microphone preamplifiers. The 552 has all the attributes of the 442, with the addition of an integrated recorder and an extra input.

“The 442’s compact mechanical construction strikes the perfect balance between access to all functions, uncluttered design and durability,” said Davey. “As always, having the individual channel outputs on the 442 gave me extra confidence, knowing that each channel is not only backed up, but isolated.”

In addition to the Sound Devices gear, Davey’s kit was carried in a Petrol field bag, along with four Lectrosonics receivers, a time-code receiver and a camera link transmitting to a Sony XDCAM. On his boom was a Sennheiser 416 and Sanken microphone heads for the four wireless mics he employed.