The Tesira SEC-4 is a modular analog input card for use with Tesira SERVER or SERVER-IO devices. SEC-4 provides 4 channels of mic or line level audio input with Acoustic Echo Cancellation. The inputs are electrically balanced and provided on plug-in barrier strip connectors. Carrying on the Biamp tradition of exceptional echo cancellation technology, the SEC-4 utilizes the next generation of the Sona AEC technology. The card also features a new Biamp algorithm, SpeechSense, which enhances speech processing by more accurately distinguishing between human speech and noise. Software control is separated into separate blocks for mic/line inputs and AEC processing. This allows the system designer to use the inputs independent of the AEC processing, and apply the AEC algorithm to inputs from a different part of the system. The SEC-4 also includes processing for Automatic Gain Control, high pass filter and noise reduction. Software configuration and control for each input shall include gain with clip indicator, phantom power on/off, mute, level, and signal invert. The acoustic echo cancellation algorithm shall be configured and controlled separately in software and include processing for high-pass filtering, automatic gain control and noise reduction.