Issue link: https://digital.copcomm.com/i/1455123
Spring 2022 – LOCAL695.ORG 31 to high-denition video, with high-resolution audio allowing for far greater manipulation and signal recovery in post production. However, the jump from 24-bit audio to 32-bit oating audio is far greater and more signicant for our industry. Both 16-bit and 24-bit formats utilize what is known as a xed-point le system, meaning that the representation of data is calculated based on a whole integer. The newly emerging 32-bit oat le format calculates data using "oating" decimal points, allowing for a far greater range of values than even a xed 32-bit prole would allow. The result is a le format that has a dynamic range of nearing 1600 dB—which could very well be the last necessary increase in audio resolution as the full range of sound believed to be possible within Earth's atmosphere is about 210 dB. As a result, properly recorded 32-bit oat les have the ability to recover near inaudible data in the signal, as well as unclip sounds that exceed 0 dBFS (what was regarded as the loudest signal level achievable in a WAV le). What's more, both can be done within a single le, allowing a whisper and a bomb blast to be successfully captured without a change in audio levels. The accompanying graphic shows the audio waveform of a line of dialog recorded in 32-bit oat format. The sound has clipped and become greatly distorted. The second image is the same le after its gain has been reduced by 26.1 dB, just enough to bring the entire waveform back into range. The distortion has been entirely removed and the dialog sounds crisp and clear. The le, despite signicant clipping, is still perfectly usable. Compare this to the third image, in which the same adjustment was made after converting the original 32-bit oat le down to a 24-bit xed format. Even at reduced volume, the uniform wave pattern shows that the distortion is still present. This le would not be usable under any circumstances. For Local 695 Production Mixers, this technology represents a useful tool in their arsenal. More forgiving les offer the ability to "split the difference" when recording scenes that vary widely in terms of sound levels being recorded on a single microphone, such as recording two performers who are speaking at different volumes off of one boom or capturing dialog that will be interrupted by a practical effect. This could mean the difference between a good take and a bad one, with takes that would have been unusable in a 24-bit format being perfectly acceptable today. However, there are some misnomers regarding this technology that must be addressed. On a recent lm set, a producer asked whether or not recording 32- bit oat les meant that we'd no longer need to be "quiet on set," in order to get good audio. The answer to this is a resounding NO. The les can't magically distinguish between an actor giving a performance and the idle chatter of a conversation behind the camera. A cellphone dinging at the wrong time can still blow a take. Professional etiquette is still a must.