Sound Devices 833, User Manual

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level microphone signal to a usable signal in the mixer. Gain is also available at the fader. Gain of digital signals or line level analog
signals is often limited. Unity gain is gain stage that neither adds or subtracts level from a signal.
Headphone monitor
Often a separate bus with a dedicated headphone volume control, the headphone monitor typically is normalled to the main left/right
output bus of a mixer. Headphone sources can often be selected among soloed tracks or buses. In some products complex
headphone monitoring of MS Stereo, LR stereo, and ambisonic sources is available.
High pass filter (audio)
Also referred to as a low-cut filter, this circuit reduces the amount of low frequency content in an audio signal. A HPF is particularly
useful when recording speech since the human voice does not generate appreciable energy at low frequencies. The HPF reduces
non-speech signals such as environmental noise, wind noise, and microphone handling noise, improving the intelligibility of speech
and reducing low frequencies from overloading the input. The high pass filter is placed in the circuit close to the microphone
preamplifier.
High pass filters are often frequency selectable, ranging from 20 Hz to 200 Hz. HPF also have a slope, generally from 3 dB/octave
to 18 dB/octave. Greater/steeper slopes offer more attenuation of frequencies just below the set filter frequency.
Input
The physical connection and associated signal type from external sources connected to a device. Inputs can include microphone
inputs on XLR connectors or USB audio inputs from a computer. Depending on the architecture of the mixing console its inputs may
be hardwired to channels or channels can be selected from different inputs.
Input limiter
A limiter circuit reduces the peak signal levels of audio, generally to prevent signal overload. Analog inputs have a maximum input
signal level that can be reached before overload/distortion is introduced. Setting the input gain correctly so that input signals do not
reach this maximum level prevents most overload conditions. In the presence of very high, unexpected signals an input limiter
changes the gain of the incoming signal and prevents it from overloading. Input limiters are sometimes compressor-type circuits with
a ratio of infinity:1, meaning that any increase to the input signal into the limiter at the limiter threshold does not increase the output
signal of the limiter.
Several parameters may be available in a limiter, including knee, ratio, release, and threshold.
Isolated track
A recorded track of an individual microphone or sound source. “Iso” recordings allow for post-record mixing of individual sound
elements.
iXML
An extensible data schema for audio and related metadata stored in broadcast WAV files. Manufacturer-specific data generated
during recording is stored in iXML.
Line level
An analog audio signal used to interconnect audio equipment. Line level may be balanced or unbalanced, referenced to +4 dBu or
-10 dBV, professional or consumer respectively.
Low cut filter
See high pass filter.
Microphone leve l
The audio signal generated by a microphone. Mic level signals are very low level, requiring a microphone preamplifier to bring them
to usable, line levels. Interconnects with microphone level signals can be subject to noise and interference.
Mid-side linking (inputs)
When mid-side (MS) stereo inputs are used and the inputs are set to MS linking and MS decoder is activated for those inputs. This
yields a stereo signal with one fader controlling overall input level and control for the “width”, or amount of the side signal added.
With an MS matrix at the input, the signal is sent to an output bus as left/right stereo. Mixers with MS matrices often allow for
discrete mid and side signal recording. In that case the MS decoder can be activated at the headphone selection to monitor left/right
stereo.
MixAssist™
An exclusive Sound Devices automatic mixing algorithm which when used across multiple microphone inputs for speech, makes
decisions about which inputs should be given priority due to speech being present vs. open, but unused inputs. This allows for
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