An excellent conference call should be devoid of audio issues such as unwanted noise,

echoing and periods when only one person at a time can speak and everyone else is

blocked out (a trait of half-duplex systems). Full-duplex systems allow interruptions and

permit simultaneous audio playback and capture. The quality of a call begins with

intelligible audio for both the near and far ends, hallmarks of which are:

• Consistent, high quality audio signal transmission with no dropouts
• Easy process for initiating, pausing, and resuming the conference
• Clear indication that the system is active or muted
• Compatibility across devices/platforms to share desktops and video easily
• Common technologies that are familiar to the user: USB, Bluetooth, etc.
• Limiting audio interface from background noise, echoes, etc.
• Properly positioned/configured microphones

Here’s what happens when you experience “call echo”: your words emerge from the far

end’s speaker, and then come back through their microphones so you hear yourself. Good

audio processing devices will remove echo by employing digital signal processing (DSP)

with acoustic echo cancellation (AEC) algorithms. Better devices will remove reverberation

and reduce noise. (Consider the noise the HVAC system kicking on can make in the

background of a conference room; better technology ensures something like this does not

disrupt your call.)