From tape to 32-bit float: the evolution of field recorders

The sound recordist's job hasn't changed that much: capture clean dialogue and deliver it in sync with the picture. What has changed is the tool. Each generation of recorders solved a problem of the previous one and brought a new way of working.

The tape era

For decades film sound was recorded on open-reel magnetic tape. The challenge wasn't just recording well, but keeping the sound from drifting out of sync with the picture. The solution was to record a sync signal (pilot tone) alongside the audio, which made it possible in the studio to match the tape speed to the film's. The slate marked the exact point to line up sound and picture by hand.

• Advantages: ruggedness, battery life and a sound with its own character.
• Limitations: one or two tracks, expensive and heavy tape, slow transfers and constant mechanical maintenance.

Digital arrives: DAT

Digital audio tape (DAT) brought location sound into the digital world: no tape hiss and copies identical to the original. Professional machines added timecode, which began to automate sync in editing. It was still tape with delicate mechanics: humidity, dust or a dirty head could cause read errors.

From media to files

The big change came when recorders started writing files to hard disks and memory cards. Critical moving parts disappeared, material could be copied to editorial in minutes and every microphone could have its own track. With metadata (scene, take and the name of each track) inside the file, the sound recordist started delivering material that was already organized.

Today: 32-bit float and remote control

Current recorders add multiple converters and 32-bit float to protect against clipping, control from phone apps, wireless timecode and, in some cases, networked audio. The recorder has gotten smaller, but the sound recordist's responsibility is still the same: correct gain, the microphone in the right place and an orderly delivery.