MT 61938 - TC 100/MT 61938

IEC 61938:2018 is available as IEC 61938:2018 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 61938:2018 gives guidance on current practice for the characteristics of multimedia analogue interfaces to achieve interoperability between equipment from different manufacturers. It is not a performance standard. Recommendations for interfaces for equipment used in vehicles, and for analogue video interfaces for broadcast and similar equipment, are not given. Refer to IEC 60958 for the interconnection of digital signals. This third edition cancels and replaces the second edition published in 2013. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) electric tolerance is standardized;
b) recommended value of output source impedance is adjusted;
c) value of 6 Ohms is additionally recommended to impedance-defined loudspeaker systems;
d) values in each table are chosen with respect to the state of the art and representative of best practice in industry.

IEC 61938:2013 gives guidance on current practice for the characteristics of multimedia analogue interfaces to achieve interoperability between equipment from different manufacturers. It is not a performance standard. This second edition cancels and replaces the first edition published in 1996 and constitutes a technical revision. It includes the following significant technical changes:
- the values in each table were chosen with respect to the state of the art and representative of best practice in industry;
- plug-in power systems and soundcard power systems are added;
- a new subclause 12.3 has been created: Interoperability of portable audio headphones/earphones and portable audio equipment;
- a new Annex A describing pairing and screening of conductors is added;
- a new Annex B describing phantom power variants for specialized applications is also added.