Concerned with the general measurement methods of the audio channels of receivers for monophonic systems and multichannel sound systems. General considerations for measurements are defined in IEC 107-1 and defined measurements to the multi-sound systems are addressed by IEC 107-3, IEC 107-4 and IEC 107-5. Deals with determining of performance and allows the comparing of equipment by listing the useful characteristics for specifications and by defining uniform measurement methods for the characteristics. Does not define performance requirements or general safety concerns.