This Recommendation updates and replaces Recommendation P.34 (1993). It recommends the transmission and quality characteristics of hands-free and loudspeaking terminals, whatever the type of terminal implementation.
However, some paragraphs apply specifically to analogue terminals.
The first part of this Recommendation recommends the transmission characteristics of hands-free terminals, as shapes for the response curves, sensitivity values, the test principles and methods, and the switching parameters.
The second part recommends the test conditions, in particular the test table, the hands-free terminal positioning according to the type of application, the test room environment, the test signals and a calibration method for the artificial mouth.
The third part proposes a set of parameters to qualify the conversation quality given by hands-free terminals. A test method is recommended for each parameter. Finally, the recommended values for some of these parameters are defined, according to a classification, based on the capability to work or not in full duplex.