You are here

Band-pass Filter (BPF)

A filter that removes or attenuates frequencies both above and below the centre frequency at which it is set, and only passes a specific range — or band — of frequencies. Band-pass filters are often used in synthesizers as tone shaping elements.

Balanced Wiring

Where protection from electromagnetic interference and freedom from earth references are required, a balanced interface is used. The term ‘balanced’ refers to identical (balanced) impedances to ground from each of two signal carrying conductors which are enclosed within an all-embracing overall electrostatic screen. This screen is grounded (to catch and remove unwanted RFI), but plays no part in passing the audio signal or providing its voltage reference. Instead, the two signal wires provide the reference for each other — the signal is conveyed ‘differentially’ and the receiver detects the voltage difference between the two signal wires. Any interference instils the same voltage on each wire (called a common mode signal) because the impedance to ground is identical for each wire. As there is therefore no voltage difference between the two signal wires, any interference is therefore ignored (rejected) completely by the receiver.

Balance

This word has several meanings in recording. It may refer to the relative levels of the left and right channels of a stereo recording (eg. Balance Control), or it may be used to describe the relative levels of the various instruments and voices within a mix (ie. Mix balance).

Aux Return

Dedicated mixer inputs used to receive external effects into the mix. Aux return channels usually have fewer facilities than normal mixer inputs, such as no EQ and access to fewer auxiliary sends. (cf. Effects Return)

Auxiliary Sends (Auxes)

A separate independent output signal derived from one or more input channels on a mixing console, usually with the option to select a pre- or post-fader source and to adjust the contribution level. Auxiliary sends from all channels are bused together before being made available to feed an internal signal processor or external physical output via the corresponding Aux Master level control. Sometimes also called Effects ('FX'), Cue or Artist sends.

Autolocator

A common facility on tape machines or other recording devices that enables specific time points to be stored and recalled. For example, you may store the start of a verse as a locate point ('marker') so that you can get the tape machine or DAW to automatically relocate the start of the verse after you've recorded an overdub.

Audio Random Access (ARA)

Jointly developed by Celemony and PreSonus in 2011, ARA relates to a data-exchange extension for DAW plug‑ins like AU, VST and RTAS, to pass information relating to an entire track, rather than just about a specific moment in time — such as pitch, tempo, rhythm etc. ARA v2 was announced in 2018 with an extended feature set including integrated undo synchronisation. Most of the popular DAWs are now compatible with ARA v2, but the only plug-ins that use it at the time of writing are Melodyne and Revoice Pro.

Audio Interface

A hardware device which acts as the physical bridge between the computer’s workstation software and the recording environment. An audio interface may be connected to the computer (via USB, Thunderbolt, FireWire, Dante, AVB or other current communication protocols) to pass audio and MIDI data to and from the computer. Audio Interfaces are available with a wide variety of different facilities including microphone preamps, DI inputs, analogue line inputs, ADAT or S/PDIF digital inputs, analogue line and digital outputs, headphone outputs, and so on. The smallest audio interfaces provide just two channels in and out, while the largest may offer 30 or more.

Pages

Subscribe to Sound On Sound RSS