1 Scope
2 References
3 Definitions
3.1 Terms defined elsewhere
3.2 Terms defined in this Recommendation
4 Abbreviations and acronyms
5 Conventions
6 Test configuration
6.1 Set-up for handset terminal
6.2 Set-up for headset
6.3 Set-up for speakerphone sets
7 Test conditions
7.1 Test signal
7.2 Test environment
7.3 Test set-up for simulated ambient noise in laboratory
8 Narrowband handset technical requirements
8.1 Sending characteristics
8.2 Receiving characteristics
8.3 Sidetone characteristics
8.4 Noise contrast and comfort noise
8.5 Weighted terminal coupling loss (TCLw)
8.6 Stability loss
8.7 Delay
8.8 Speech clipping
8.9 Acoustic safety of telephone user
8.10 Speech quality in presence of ambient noise
9 Narrowband headset technical requirements
9.1 Headset sending characteristics
9.2 Headset receiving characteristics
9.3 Sidetone characteristics
9.4 TCLw
9.5 Acoustic safety of telephone user
9.6 Delay
10 Narrowband speakerphone sets technical requirements
10.1 Loudspeaker sending characteristics
10.2 Speakerphone set receiving characteristics
10.3 TCLw
10.4 Switching characteristics
10.5 Double talk performance
10.6 Background noise transmission and comfort noise injection
11 Wideband handset technical requirements
11.1 Sending characteristics
11.2 Receiving characteristics
11.3 Sidetone characteristics
11.4 Noise contrast and comfort noise
11.5 TCLw
11.6 Stability loss
11.7 Delay
11.8 Speech clipping
11.9 Acoustic safety of telephone user
11.10 Speech quality in the presence of ambient noise
12 Wideband headset technical requirements
12.1 Headset sending characteristics
12.2 Headset receiving characteristics
12.3 Sidetone characteristics
12.4 TCLw
12.5 Acoustic safety of telephone user
12.6 Delay
13 Wideband speakerphone sets technical requirements
13.1 Loudspeaker sending characteristics
13.2 Speakerphone set receiving characteristics
13.3 TCLw
13.4 Switching characteristics
13.5 Double talk performance
13.6 Background noise transmission and comfort noise injection