Modern, sleek design encompasses the latest in acoustic technology. Three built-in microphones ensure that you can be heard wherever you are in the room. Conference phone has full duplex communications, allowing for simultaneous two-way conversations. Echo and noise cancellation, provided by the patented SoundClear DSP (Digital Signal Processing) chip, gives you unprecedented clarity of sound. Whether your phone system is analog or digital, you can experience quality conferencing at an affordable price with the Aura SoHo. Includes three built-in and two external microphones for larger rooms. Telephone Type: Conferencing; Maximum Wireless Range: 20 ft x 20 ft; Speakerphone: Base; Volume Control: Speakerphone.