This Recommendation provides audio performance requirements and test methods for hands-free telephones capable of transmitting an audio bandwidth extending beyond the conventional telephony bandwidth of 300 to 3400 Hz
ITU-T P.341-2005 history
2011ITU-T P.341-2011 (Pre-Published) Transmission characteristics for wideband digital loudspeaking and hands-free telephony terminals
2005ITU-T P.341-2005 Transmission characteristics for wideband (150-7000 Hz) digital hands-free telephony terminals Study Group 12