Glossary of Terms
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Ambient noise -
Low-level noise created by environmental factors such as fans, air conditioners,
heaters, wind noise, etc.
Attack time -
Describes the amount of time it takes compressor circuitry to react to and reduce the
gain of incoming signal. A compressor set to a fast attack time kicks in almost immediately and
catches transient signals of very brief duration, reducing their level and thus "softening" the sound.
A slow attack time allows transients to pass through unscathed before compression begins on the rest
of the signal. The 1176LN attack time ranges from 20 to 800 microseconds.
Auxiliary (Aux) send
- A mixer bus output designed to combine and send multiple signals to an
external processor or monitor system.
Balanced
- Audio cabling that uses two twisted conductors enclosed in a single shield, thus allowing
relatively long cable runs with minimal signal loss and reduced induced noise such as hum.
Bus
- The point in an audio mixer where various signals are blended together.
Bus insert
- An insert across a mixer bus.
Channel
- A functional path in an audio circuit. A mixer provides multiple channels, each with its own
dedicated input(s) and several outputs, such as buses, auxiliary sends, etc.
Channel insert
- An insert across a mixer channel.
Class A
- A design technique used in electronic devices such that their active components are drawing
current and working throughout the full signal cycle, thus yielding a more linear response. This
increased linearity results in fewer harmonics generated, hence lower distortion in the output signal.
Clipping -
A particularly harsh form of audio distortion, caused when the loudness of an incoming
signal exceeds a digital audio recording device’s capability to represent its amplitude. When that
happens, the peaks of the signal simply get “clipped” off, thus drastically changing the waveform and
yielding an especially unpleasant sound.
Compression
-
The process of automatically reducing the level of peaks in an audio signal so that the
overall dynamic range—that is, the difference between the loudest sections and the softest ones—is
reduced, or compressed. “Compression” is sometimes described as “gain reduction” or “peak
reduction.”
Compression ratio
-
A term that describes the amount of increase required in the incoming signal in
order to cause a 1 dB increase in output. A ratio of 4:1, for example, means that any time there is an
increase of 4 decibels in the loudness of the input signal, there will only be a 1 dB increase in output
signal. When compression ratios of 12:1 or higher are being used, the device is instead said to be
limiting.
DAW
- An acronym for “Digital Audio Workstation”—that is, any device that can record, play back,
edit, and process digital audio.
dB
- Short for “decibel,” a logarithmic unit of measure used to determine, among other things, power
ratios, voltage gain, and sound pressure levels.
