IEC 61842 pdf download

IEC 61842 pdf download.Microphones and earphones for speech communications
1 Scope
This standard applies to the microphone part and earphone part of handsets, headsets or earsets for speech communications, and also to the microphone units and earphone units of built-in handsets, headsets or earsets. The object of this standard is to establish definitions relating to these electroacoustic transducers, and to standardize the characteristics to be specified and the relevant methods of measurement. This does not exclude the use of other methods of measurement which can be shown to give the same or more reliable results.
3 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply. 3.1 Classification 3.1.1 handset assembly for speech communications, which is a handle including a microphone part and an earphone part suitable to be held by the talker’s hand 3.1.2 headset assembly for speech communications, which consists of a holder to put on the talker’s head, one or two earphone parts and a microphone part, so as to keep the talker’s hands free 3.1.3 earset assembly for speech communications, which consists of an earphone part and a microphone part, so as to keep the talker’s hands free, without a holder to put on the talker’s head NOTE The distinction between an earset and a headset is as complicated as it is between an earphone and a headphone. Table 1 explains the definitions of earphone, headphone, earset and headset used in this standard. 3.1.4 microphone for speech communications: a) part of a handset, an earset or a headset, which functions as a microphone (an acousto- electrical transducer) b) assembly of a microphone unit for speech communications and a case for measurement purposes, including acoustical circuit elements so as to obtain practical frequency characteristics NOTE 1 A microphone for speech communications is understood to include devices, if any, such as amplifiers or impedance matching transformers up to the output terminals. NOTE 2 A microphone for speech communications is called merely “microphone”, or “microphone part” of a handset, of an earset or of a headset, in Clause 4 of this standard and beyond. 3.1.5 earphone for speech communications a) part of a handset, an earset or a headset, which functions as an earphone (an electro- acoustic transducer) b) assembly of an earphone unit for speech communications and a case for measurement purposes, including acoustical circuit elements so as to obtain practical frequency characteristics NOTE 1 Any component which is intended by the manufacturer as an integral part of the earphone is included during measurements. NOTE 2 An earphone for speech communications is called merely “earphone”, or “earphone part” of a handset, of an earset or of a headset, in Clause 4 of this standard and beyond.3.1.6 microphone unit for speech communications acousto-electrical transducer installed in a handset, in an earset or in a headset to pick up the talker’s speech in the vicinity of his/her mouth NOTE The microphone unit for speech communications is called merely a “microphone unit” in Clause 4 of this standard and beyond. 3.1.7 earphone unit for speech communications electroacoustic transducer installed in a handset, in an earset or in a headset to radiate sound signal in the vicinity of the listener’s ear NOTE The earphone unit for speech communications is called merely an “earphone unit” in Clause 4 of this standard and beyond. 3.1.8 case for unit measurement case in which a microphone unit or an earphone unit for speech communications is installed for measurement. It includes additional acoustic circuit elements so as to obtain practical frequency characteristics, if necessary