SN EN 61938 : 1997

1 General
    1.1 Scope
    1.2 Normative references
2 General conditions and definitions
    2.1 General conditions
    2.2 Definitions
3 Power supply
    3.1 Alternating current (a.c.) power supply voltages
          and frequencies
    3.2 Direct current (d.c.) power supply voltages
    3.3 Power supply feed for microphones
4 Interconnections
    4.1 Connections
    4.2 Connectors
5 Marking and symbols for marking
    5.1 Marking
    5.2 Symbols for marking
6 Electrical matching values
    6.1 General purpose output/input
    6.2 General purpose audio output/input
    6.3 General purpose video input/output
7 Matching of microphones and amplifiers
    7.1 Microphones (excluding piezoelectric types)
    7.2 Microphones with built-in amplifier
    7.3 Power supply feed for electret microphones fed
          by a separate conductor
    7.4 Phantom supply system
    7.5 A-B supply system
    7.6 Polarity of the audiofrequency voltage
8 Matching of record-playing units (pick-ups) and
    amplifiers
9 Matching of loudspeakers and amplifiers
    9.1 Single unit loudspeakers
    9.2 Loudspeaker systems
    9.3 Voltage (or power) matching of amplifiers and
          loudspeakers
    9.4 Polarity of the sound pressure
10 Matching of headphones and amplifiers
11 Matching of amplifiers to amplifiers
    11.1 Pre-amplifiers and power amplifiers for general
          purpose and sound reinforcement
    11.2 Broadcast and similar line amplifiers
Tables
1 Direct current (d.c.) power supply voltages and tolerances
2 General purpose matching values for audio signals
3 General purpose matching values for video signals
4 Matching values for microphones and amplifiers
5 Matching values for analogue record-playing units and
    amplifiers
6 Matching values for impedance-defined loudspeaker
    systems
7 Matching values for constant voltage loudspeaker systems
8 General purpose matching values for headphones and
    amplifiers
9 Matching values for pre-amplifiers and power amplifiers
10 Matching values for broadcast and similar line amplifiers
11 Required values for phantom supply systems
12 Required values for A-B power supply systems
Figures
1 Audio and video sources and destinations
2 Example of phantom power supply system
3 Example of A-B power supply system
Annex ZA (normative) Normative references to international
publications with their corresponding European publications

Applicable to electrical matching values for interconnecting analogue signals among audio, video and AV system equipment. Covers audio but not video signals for broadcasting and similar use. Does not include the 21 contact connector as in IEC 807-9, or matching values for vehicle applications.