Jabra LINK 850 Audio Processor for Deskphone and Softphone Peak Stop - Peak Stop technology immediately removes potentially harmful loud sounds or tones before they reach your ears and keeps the sound level within the safe range to protect your hearing. Noise Canceling Microphone reduces unwanted background noise and the noise-canceling microphones reduce unwanted background noise and are ideal in crowded and noisy, open office environments. DSP (Digital Signal Processing) Tone Control Equalizer Dynamic Volume Control