Universal Audio Apollo Software - Manual (Page 133)

Apollo Software Manual Glossary 133
Chapter 10: Glossary
A/D An acronym for “Analog to Digital,” which refers to the conversion of analog signals
to digital data.
Acronym A word formed from the first letters of other words (e.g., GUI, ADAT, TRS, etc.).
ADAT An acronym for “Alesis Digital Audio Tape.” ADAT was the name given to the
Alesis-branded products of the 1990s which recorded eight tracks of digital audio on a
standard S-VHS video cassette. The term now generally refers to the 8-channel optical
“Lightpipe” connection that is used in a wide range of digital products from many manu-
facturers.
AES (sometimes written as “AES/EBU“) The name of a digital audio transfer standard
jointly developed by the American-based Audio Engineering Society and the European
Broadcast Union. Designed to carry two channels of 16-, 20- or, 24-bit digital audio at
sampling rates of up to 192kHz, the most common AES physical interconnect utilizes a
3-conductor 110 ohm twisted pair cable, terminating at standard XLR connectors. (See
“Dual Wire” and “Single Wire”)
Analog Literally, an analog is a replica or representation of something. In audio signals,
changes in voltage are used to represent changes in acoustic sound pressure. Note that
analog audio is a continuous representation, as opposed to the quantized, or discrete
“stepped” representation created by digital devices. (See “Digital”)
API Acronym for Application Programming Interface. A software layer between an operat-
ing system and third-party hardware (such as an audio interface) and/or software (such
as a DAW). For example, a computer OS’s audio API enables audio hardware and audio
software from different vendors to communicate with the OS and each other.
ASIO Acronym for Audio Stream Input/Output. ASIO is an audio interface driver protocol
for Windows operating systems developed by Steinberg GmbH.
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.
Bit A contraction of the words “binary” and “digit,” a bit is a number used in a digi-
tal system, and it can have only one of two values: 0 or 1. The number of bits in each
sample determines the theoretical maximum dynamic range of the audio data, regardless
of sample rate being used. Each additional bit adds approximately 6 dB to the dynamic
range of the audio. In addition, the use of more bits helps capture quieter signal more
accurately. (See “Sample” and “Dynamic range”)
Bit Depth (See “Bit Resolution”)