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Music & Audio Industry Acronyms

Music & Audio Industry Acronyms

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This glossary explains the operational, technical, commercial, rights, safety, and performance terminology commonly encountered in the Media & Entertainment sector’s music ecosystem. It helps executives and practitioners navigate the standards, systems, formats, metrics, and organizations central to the Music & Audio Practice.

A B C D E F G H I J K L M N O P Q R S T U V W X

A
A&R Artists and Repertoire:
The record-label function responsible for discovering artists, guiding repertoire choices, and coordinating creative development and recording projects.
A2IM American Association of Independent Music:
A United States trade association representing independent record labels and advocating on market access, policy, licensing, and commercial standards.
AAC Advanced Audio Coding:
A lossy digital audio codec widely used by streaming services, mobile devices, downloads, and internet-delivered audio.
AAX Avid Audio eXtension:
A plug-in format used in Pro Tools for software instruments, signal processing, and other professional production tools.
ACR Automatic Content Recognition:
Technology that identifies audio by matching fingerprints or watermarks, supporting usage monitoring, rights administration, audience measurement, and royalty verification.
ADC Analog-to-Digital Converter:
A device or circuit that converts an analog audio signal into digital samples for recording, processing, storage, or transmission.
ADM Audio Definition Model:
An International Telecommunication Union metadata model that describes objects, channels, positions, and presentation instructions for immersive and personalized audio.
ADSR Attack, Decay, Sustain, Release:
The four common stages of an amplitude or modulation envelope used to shape synthesized and sampled sounds.
AEU Album-Equivalent Unit:
A consumption measure that combines album sales, track sales, and qualifying streams using defined conversion ratios.
AES Audio Engineering Society:
A professional organization that develops audio engineering standards and convenes specialists across recording, production, acoustics, and audio technology.
AES67 Audio Engineering Society Standard 67 for High-Performance Streaming Audio-over-IP Interoperability:
A standard enabling compatible, low-latency audio transport between professional networked-audio systems from different vendors.
AES/EBU Audio Engineering Society/European Broadcasting Union:
A common name for the professional two-channel digital audio interface standardized as AES3 and typically carried over balanced connections.
AFL After-Fade Listen:
A mixing-console monitoring function that auditions a signal after its channel fader, allowing operators to assess the level sent to a mix or bus.
AFM American Federation of Musicians:
A labor union representing professional instrumental musicians in the United States and Canada, including performers working on recordings and media productions.
AIFF Audio Interchange File Format:
An uncompressed or losslessly compressed audio file format commonly used in professional production and Apple-based workflows.
ALAC Apple Lossless Audio Codec:
A lossless compression format that reduces file size while preserving the original digital audio data.
AoIP Audio over Internet Protocol:
The transport of professional audio and related control or synchronization data across standard internet-protocol networks.
APRA AMCOS Australasian Performing Right Association and Australasian Mechanical Copyright Owners Society:
A collective management organization administering performing and mechanical rights for songwriters, composers, and music publishers in Australia and New Zealand.
ARPU Average Revenue per User:
A subscription-economics metric calculated by dividing revenue by the relevant user or subscriber base, helping assess pricing, mix, and monetization performance.
ASCAP American Society of Composers, Authors and Publishers:
A United States performing rights organization that licenses public performances and distributes royalties to affiliated writers and publishers.
ASIO Audio Stream Input/Output:
A low-latency audio driver protocol developed by Steinberg for communication between professional audio software and hardware.
ASR Automatic Speech Recognition:
Technology that converts spoken audio into machine-readable text for transcription, search, accessibility, editing, and content analysis.
AU Audio Units:
Apple’s plug-in architecture for software instruments and audio effects used by compatible macOS and iOS production applications.
AVB Audio Video Bridging:
A family of networking standards providing synchronized, time-sensitive transport for professional audio and video over Ethernet.
B
BIEM Bureau International de l’Edition Mécanique:
The international organization representing mechanical-rights societies and coordinating licensing frameworks for the reproduction of musical works.
BMI Broadcast Music, Inc.:
A United States performing rights organization that licenses public performances and distributes royalties to songwriters, composers, and publishers.
BPI British Phonographic Industry:
The trade association representing the United Kingdom’s recorded-music sector, including major and independent record companies.
BPM Beats per Minute:
A measure of musical tempo used in composition, performance, synchronization, production, and catalog metadata.
BWF Broadcast Wave Format:
An extension of the Waveform Audio File Format that embeds production metadata, time references, and other information needed for professional interchange.
C
CAE Compositeur, Auteur et Éditeur:
A legacy identifier for composers, authors, and publishers that was superseded by the Interested Parties Information system but remains present in older rights data.
CAF Core Audio Format:
An Apple-developed audio container designed to support large files, extensive metadata, and a wide range of audio encodings.
CBR Constant Bit Rate:
An encoding method that maintains a fixed data rate throughout an audio file or stream, producing predictable bandwidth and file sizes.
CD Compact Disc:
An optical disc format used for distributing digital recordings and other audio content in physical form.
CD-DA Compact Disc Digital Audio:
The technical format defined by the Red Book specification for consumer audio compact discs.
CISAC Confédération Internationale des Sociétés d’Auteurs et Compositeurs:
A global confederation of authors’ societies that promotes rights-management standards, identifiers, data exchange, and international cooperation.
CLAP CLever Audio Plug-in API:
An open plug-in standard designed for efficient communication between digital audio workstations and software instruments or effects.
CMO Collective Management Organization:
An entity that licenses rights, collects royalties, and distributes proceeds on behalf of songwriters, publishers, performers, or recording owners.
CRB Copyright Royalty Board:
The United States tribunal that sets and adjusts certain statutory copyright royalty rates and terms, including rates affecting musical works and sound recordings.
CV Control Voltage:
An electrical signal used to control pitch, filters, amplitude, and other parameters in modular and analog synthesizer systems.
CWR Common Works Registration:
A standardized format for registering musical works and ownership shares between publishers and rights societies.
D
DAC Digital-to-Analog Converter:
A device or circuit that converts digital audio samples into an analog signal for monitoring, amplification, or playback.
Dante Digital Audio Network Through Ethernet:
Audinate’s widely deployed networked-audio technology for routing multichannel, low-latency audio and control data over internet-protocol networks.
DAW Digital Audio Workstation:
Software or an integrated system used to record, edit, arrange, mix, process, and master audio.
dB Decibel:
A logarithmic unit used to express ratios between signal levels, acoustic pressures, power levels, or gains.
dB(A) A-weighted Decibel:
A sound-level unit applying a frequency weighting that approximates human hearing sensitivity and is commonly used for occupational and environmental noise limits.
dBFS Decibels relative to Full Scale:
A digital level unit in which zero represents the maximum representable sample level and lower levels are expressed as negative values.
dB SPL Decibels Sound Pressure Level:
A logarithmic measure of acoustic pressure relative to the standard reference pressure in air, used for monitoring, calibration, and hearing-safety assessments.
dBTP Decibels True Peak:
A unit expressing estimated inter-sample peak level relative to digital full scale, helping prevent distortion during conversion and encoding.
DDEX Digital Data Exchange:
A standards-setting organization whose message formats support the exchange of release, recording, work, rights, sales, and royalty data.
DDP Disc Description Protocol:
A professional delivery format that packages mastered audio, track sequencing, identifiers, and disc metadata for compact-disc manufacturing or replication.
DI Direct Injection:
A method and device for connecting an instrument-level or unbalanced source to a balanced microphone-level input for recording or reinforcement.
DMCA Digital Millennium Copyright Act:
A United States law governing digital copyright enforcement, online-service safe harbors, anti-circumvention rules, and statutory licensing for certain digital audio transmissions.
DMM Direct Metal Mastering:
A vinyl-mastering process that cuts audio directly into a metal-coated disc rather than a lacquer master.
DPD Digital Phonorecord Delivery:
A digital transmission of a sound recording that results in an identifiable reproduction, a concept important to United States mechanical licensing.
DPID DDEX Party Identifier:
A unique identifier assigned to organizations participating in standardized music-data exchanges, reducing ambiguity in automated transactions.
DRM Digital Rights Management:
Technology used to control access, copying, playback, or distribution of protected digital content according to license conditions.
DSD Direct Stream Digital:
A high-rate one-bit audio encoding method associated with Super Audio CD and some high-resolution recording and distribution workflows.
DSP Digital Service Provider:
A platform that delivers music or other audio digitally through streaming, downloads, or related on-demand services.
DSP Digital Signal Processing:
The mathematical manipulation of digitized audio for filtering, equalization, compression, synthesis, analysis, restoration, or effects.
DSR Digital Sales Reporting:
A family of standardized messages used by digital services to report sales, streams, usages, and associated commercial data to rights holders.
E
EAN European Article Number:
A standardized retail product identifier, now part of the Global Trade Item Number system, that may be assigned to physical music releases.
EBU R128 European Broadcasting Union Recommendation R 128:
A loudness-normalization recommendation based on program loudness, loudness range, and true-peak measurement that also informs mastering and delivery practices.
EP Extended Play:
A music release longer than a typical single but generally shorter than a full-length album.
EQ Equalization:
The adjustment of frequency-dependent gain to shape tone, correct problems, create separation, or meet production objectives.
ERN Electronic Release Notification:
A standardized message suite used to communicate release metadata, resource information, commercial terms, and availability to digital services.
F
FFT Fast Fourier Transform:
An efficient algorithm for converting time-domain audio into a frequency-domain representation for spectral analysis and signal processing.
FIR Finite Impulse Response:
A digital-filter architecture with a finite-duration response, often used for equalization, crossover processing, and phase-controlled filtering.
FLAC Free Lossless Audio Codec:
An open compression format that reduces audio file size without discarding any source data.
FM Frequency Modulation:
A synthesis technique in which one signal changes another signal’s frequency, producing harmonically complex tones used in electronic instruments and sound design.
G
GEMA Gesellschaft für musikalische Aufführungs- und mechanische Vervielfältigungsrechte:
Germany’s collective management organization for musical performing and mechanical reproduction rights.
GMR Global Music Rights:
A United States performing rights organization representing a selective repertoire of songwriters, composers, and publishers.
GRid Global Release Identifier:
An identifier designed to distinguish digital music releases and support reliable communication across rights and distribution systems.
GTIN Global Trade Item Number:
A standardized identifier for trade items, including physical music products sold through retail and distribution channels.
H
HFA Harry Fox Agency:
A United States provider of mechanical licensing, royalty administration, and music-rights data services.
HOA Higher-Order Ambisonics:
A spatial-audio technique that uses multiple spherical-harmonic channels to capture or reproduce a three-dimensional sound field with increased directional resolution.
HRTF Head-Related Transfer Function:
A model of how a listener’s head, torso, and ears filter sounds from different directions, enabling binaural and personalized spatial-audio rendering.
Hz Hertz:
The unit of frequency equal to one cycle per second, used to specify pitch, sample rates, bandwidth, and equipment response.
I
IEC International Electrotechnical Commission:
A global standards body whose work covers audio equipment, electroacoustics, connectors, measurement methods, and hearing-safety technologies.
IEM In-Ear Monitor:
An earpiece-based monitoring system that provides performers with a controlled personal mix while reducing reliance on stage loudspeakers.
IFPI International Federation of the Phonographic Industry:
A global organization representing the recorded-music industry and administering standards and programs related to recording identifiers, market data, and anti-piracy efforts.
IIR Infinite Impulse Response:
A digital-filter architecture using feedback to produce an impulse response that theoretically continues indefinitely, often with low computational cost.
IMPALA Independent Music Publishers and Labels Association:
The organization now known as the Independent Music Companies Association represents independent music businesses across Europe.
IPI Interested Parties Information:
A global identification system used by rights societies to distinguish songwriters, composers, publishers, and other parties associated with musical works.
ISNI International Standard Name Identifier:
A persistent identifier for public identities such as artists, creators, performers, and organizations, helping reconcile names across databases.
ISO International Organization for Standardization:
A global standards body responsible for specifications relevant to audio coding, media formats, metadata, identifiers, and quality systems.
ISRC International Standard Recording Code:
The standard identifier assigned to an individual sound recording or music video recording for tracking, reporting, and rights administration.
ISWC International Standard Musical Work Code:
The standard identifier for an underlying musical work, distinct from identifiers assigned to particular recordings.
ITU-R BS.1770 International Telecommunication Union Radiocommunication Sector Recommendation BS.1770:
The foundational specification for measuring audio program loudness and true-peak level, used by multiple delivery and normalization standards.
J
JASRAC Japanese Society for Rights of Authors, Composers and Publishers:
A major Japanese collective management organization licensing musical works and distributing royalties to rights holders.
K
kbps Kilobits per Second:
A data-rate measure commonly used to specify the bitrate and expected bandwidth or quality of compressed digital audio.
L
LADSPA Linux Audio Developer’s Simple Plugin API:
An open plug-in standard for audio effects and signal-processing software on Linux systems.
LAeq A-Weighted Equivalent Continuous Sound Level:
The steady A-weighted sound level containing the same acoustic energy as a varying sound over a specified period, commonly used in noise-exposure assessment.
LCR Left, Center, Right:
A three-channel frontal loudspeaker configuration used in mixing, monitoring, and spatial-audio production.
LFE Low-Frequency Effects:
A dedicated channel in multichannel audio systems carrying selected low-frequency content, distinct from general bass management.
LFO Low-Frequency Oscillator:
An oscillator used to modulate parameters such as pitch, amplitude, filter cutoff, or spatial position in synthesis and effects processing.
LKFS Loudness, K-Weighted, relative to Full Scale:
A unit for program loudness measured with standardized K-weighting and referenced to digital full scale.
LP Long Play:
A full-length record format, typically a 12-inch vinyl release played at 33⅓ revolutions per minute, and a common shorthand for an album.
LRA Loudness Range:
A statistical measure describing loudness variation across a program, useful for evaluating dynamics and delivery suitability.
LTC Linear Timecode:
An audio-frequency representation of timecode used to synchronize recording systems, sequencers, consoles, and other production equipment.
LU Loudness Unit:
A relative unit for expressing differences in measured program loudness, with one unit corresponding to one decibel.
LUFS Loudness Units relative to Full Scale:
A standardized measure of perceived program loudness used in mastering, streaming normalization, and delivery quality control.
LV2 LADSPA Version 2:
An extensible open standard for audio plug-ins, software instruments, and related processing tools, particularly on Linux platforms.
M
MADI Multichannel Audio Digital Interface:
A professional digital-audio standard that transports many channels over coaxial or optical connections between consoles, converters, and recorders.
MCPS Mechanical-Copyright Protection Society:
A United Kingdom organization that administers mechanical rights in musical works and forms part of PRS for Music.
MFN Most Favored Nations:
A contractual provision requiring one party’s terms to be no less favorable than specified terms granted to comparable parties, often affecting music licenses and contributor agreements.
MIDI Musical Instrument Digital Interface:
A technical standard enabling electronic instruments, controllers, computers, and production software to exchange performance and control data.
MLC Mechanical Licensing Collective:
The entity designated under United States law to administer blanket mechanical licenses for eligible digital uses and distribute associated royalties.
MMA Music Modernization Act:
A United States statute that reformed mechanical licensing for digital music, addressed legacy recordings, and changed aspects of producer and rights-holder payments.
MP3 Moving Picture Experts Group-1 Audio Layer III:
A widely adopted lossy audio compression format that enabled compact downloads, portable playback, and early digital distribution.
MPEG Moving Picture Experts Group:
The standards group responsible for major audiovisual compression and container specifications used in digital audio distribution.
MQA Master Quality Authenticated:
A proprietary audio encoding and authentication technology encountered in high-resolution music catalogs and playback systems.
M/S Mid/Side:
A stereo recording and processing technique representing common center information separately from the difference between left and right channels.
MTC MIDI Time Code:
A synchronization method that carries timecode information through Musical Instrument Digital Interface messages for coordination among production systems.
MWN Musical Work Notification:
A standardized message suite for exchanging musical-work, rights, ownership, and licensing information among publishers and rights organizations.
N
NAMM National Association of Music Merchants:
A global trade association for musical-instrument, professional-audio, and music-technology manufacturers, distributors, retailers, and service providers.
NIOSH National Institute for Occupational Safety and Health:
The United States research agency that issues recommendations on occupational noise exposure and hearing-loss prevention relevant to studios and audio workplaces.
NMPA National Music Publishers’ Association:
A United States trade association representing music publishers and their interests in licensing, copyright policy, litigation, and royalty administration.
NOI Notice of Intention:
A formal notice historically used to obtain a compulsory mechanical license for distributing a musical work under United States copyright law.
NRR Noise Reduction Rating:
A standardized laboratory rating indicating the attenuation provided by hearing-protection devices under specified conditions.
O
OAC Official Artist Channel:
A YouTube channel designation that consolidates an artist’s eligible music presence and provides specialized catalog, analytics, and audience-management features.
OSC Open Sound Control:
A network protocol for exchanging high-resolution control messages among instruments, audio software, consoles, and interactive media systems.
OSHA Occupational Safety and Health Administration:
The United States workplace-safety regulator responsible for enforceable occupational noise-exposure and hearing-conservation requirements.
P
P&D Pressing and Distribution:
An arrangement under which a partner manufactures physical records and distributes them, usually in return for fees or a share of receipts.
PCM Pulse-Code Modulation:
The standard method of representing sampled audio as numerical amplitude values, underlying compact discs, Waveform Audio files, and many production systems.
PFL Pre-Fade Listen:
A console monitoring function that auditions a channel before its fader, allowing level checks without changing the main mix.
PPD Published Price to Dealer:
A wholesale-price basis historically used to calculate artist royalties on physical-record sales in some recording agreements.
PPL Phonographic Performance Limited:
A United Kingdom music-licensing company that collects and distributes public-performance and broadcast royalties for recording owners and performers.
PRO Performing Rights Organization:
An organization that licenses public performances of musical works and distributes collected royalties to affiliated songwriters, composers, and publishers.
PRS Performing Right Society:
The performing-rights component of PRS for Music, which administers public-performance rights for writers, composers, and publishers in the United Kingdom.
PTP Precision Time Protocol:
A network synchronization protocol used to align clocks accurately across professional networked-audio devices.
PVC Polyvinyl Chloride:
The thermoplastic material conventionally used to manufacture vinyl records, with formulation and recycled content affecting pressing performance and sustainability.
Q
QC Quality Control:
The systematic review of audio, metadata, sequencing, identifiers, and delivery specifications before a recording or release enters manufacturing or distribution.
R
RCA Radio Corporation of America:
The origin of the name for a widely used coaxial connector found on consumer and semi-professional analog and digital audio equipment.
RDR-N Recording Data and Rights Notification:
A standardized message for communicating recording metadata, contributors, rights claims, and related studio information through the value chain.
RIAA Recording Industry Association of America:
The trade association representing major recorded-music companies in the United States and operating recognized sales-certification programs.
RIN Recording Information Notification:
A studio-focused standard for capturing and exchanging information about sessions, recordings, contributors, equipment, and rights-related data.
RMS Root Mean Square:
A mathematical measure used to describe the effective magnitude of a varying audio signal, often as an indication of average level.
RPM Revolutions per Minute:
The rotational-speed measure used for vinyl records, commonly including 33⅓, 45, and 78 revolutions per minute.
RSS Really Simple Syndication:
The feed format used to publish and distribute podcast episodes, metadata, media-file locations, and updates to listening platforms.
RTAS Real-Time AudioSuite:
A legacy Avid plug-in format used for real-time audio processing in earlier Pro Tools systems.
RTP Real-time Transport Protocol:
A network protocol for carrying time-sensitive audio and other media streams, including within interoperable professional audio-over-network systems.
S
SACD Super Audio CD:
A high-resolution optical disc format using Direct Stream Digital encoding and supporting stereo or multichannel audio.
SACEM Société des auteurs, compositeurs et éditeurs de musique:
France’s principal collective management organization for songwriters, composers, and music publishers.
SCAPR Societies’ Council for the Collective Management of Performers’ Rights:
An international organization that develops cooperation, data systems, and practices for the cross-border administration of performers’ neighboring rights.
SCMS Serial Copy Management System:
A copy-control mechanism in certain consumer digital-audio equipment that permits limited copying while restricting subsequent digital generations.
SEA Streaming-Equivalent Album:
A consumption measure that converts a defined number of on-demand streams into the equivalent of one album unit.
SESAC Society of European Stage Authors and Composers:
The historical expansion of the name used by a United States performing rights organization that licenses a selectively affiliated repertoire.
SID Source Identification Code:
A code applied during optical-disc mastering or molding to identify manufacturing facilities and support supply-chain traceability and anti-piracy controls.
SMPTE Society of Motion Picture and Television Engineers:
A standards organization whose timecode and synchronization specifications are widely used in recording, music-for-picture, and post-production workflows.
SNR Signal-to-Noise Ratio:
The ratio between desired signal level and background noise, used to evaluate recordings, transmission paths, converters, and equipment performance.
SOCAN Society of Composers, Authors and Music Publishers of Canada:
A Canadian collective management organization administering performing and reproduction rights in musical works.
S/PDIF Sony/Philips Digital Interface Format:
A consumer and semi-professional digital-audio interface that carries two-channel audio over coaxial or optical connections.
SPL Sound Pressure Level:
A measure of acoustic pressure used to calibrate monitoring environments, evaluate loudspeaker output, and manage hearing risk.
SRC Sample-Rate Conversion:
The process of converting digital audio between sampling frequencies while controlling aliasing, distortion, and other artifacts.
SRCO Sound Recording Copyright Owner:
The party that owns or controls copyright in a sound recording and may be entitled to licensing income and digital-performance royalties.
SRLP Suggested Retail List Price:
A historical retail-price benchmark used in some recording agreements to calculate artist royalties on physical products.
STC Sound Transmission Class:
A single-number rating of how effectively a building partition reduces airborne sound transmission, relevant to studio design and isolation.
STFT Short-Time Fourier Transform:
A signal-analysis technique that divides audio into overlapping time segments to show how spectral content changes over time.
T
TDM Time-Division Multiplexing:
A method of carrying multiple signal channels by assigning each a repeating time slot, also associated with legacy Pro Tools processing systems.
TEA Track-Equivalent Album:
A consumption measure that converts a defined number of individual track sales into the equivalent of one album unit.
THD Total Harmonic Distortion:
A measure of harmonic components added by audio equipment relative to the original signal, used to evaluate fidelity and system performance.
THD+N Total Harmonic Distortion plus Noise:
A combined measurement of distortion products and noise relative to the test signal, commonly used in audio-equipment specifications.
TPDF Triangular Probability Density Function:
A common statistical distribution used to generate dither when reducing digital-audio bit depth, helping prevent correlated quantization distortion.
TRS Tip-Ring-Sleeve:
A three-conductor phone connector used for balanced mono signals, unbalanced stereo signals, inserts, and headphone connections.
TS Tip-Sleeve:
A two-conductor phone connector commonly used for unbalanced instrument-level and line-level audio signals.
TTS Text-to-Speech:
Technology that generates spoken audio from written text for narration, accessibility, localization, demonstrations, and synthetic-voice production.
TWA Time-Weighted Average:
An average exposure level calculated over a defined work period and used to assess occupational noise risk.
U
UGC User-Generated Content:
Media created or uploaded by platform users that may incorporate music and therefore require identification, licensing, claims management, or revenue sharing.
UPC Universal Product Code:
A standardized product identifier assigned to a release or physical music product for retail, distribution, reporting, and catalog management.
V
VBAP Vector Base Amplitude Panning:
A spatial-audio method that positions virtual sound sources by distributing gain across selected loudspeakers.
VBR Variable Bit Rate:
An encoding method that allocates more data to complex audio passages and less to simpler passages to improve quality or efficiency.
VCA Voltage-Controlled Amplifier:
A circuit whose gain is controlled by another voltage, used in synthesizers, dynamics processors, consoles, and automation systems.
VCF Voltage-Controlled Filter:
A filter whose cutoff or other parameters are changed by a control voltage, making it central to analog and modular synthesis.
VCO Voltage-Controlled Oscillator:
An oscillator whose frequency is governed by a control voltage and that serves as a primary sound source in many analog synthesizers.
VST Virtual Studio Technology:
Steinberg’s widely supported plug-in standard for integrating software instruments and audio effects with digital production applications.
W
WAV Waveform Audio File Format:
A widely used container for uncompressed pulse-code modulation audio and other encodings in recording, mastering, and distribution workflows.
WIN Worldwide Independent Network:
A global organization connecting independent music trade associations and companies around policy, rights, market access, and industry standards.
WMA Windows Media Audio:
A family of Microsoft audio codecs and file formats encountered in legacy digital catalogs, downloads, and playback systems.
X
XLR X Series, Latch, Rubber:
The historical naming origin for a locking circular connector family widely used for balanced analog audio, microphones, digital audio, and control signals.