For optimum echo-cancelled voice quality and enhancement choose the A200D Model with Octasic® DSP Daughterboard Hardware Echo Canceller. One DSP echo canceller on the A200D Base Card will support Telco-grade hardware echo cancellation on all channels up to the card's maximum configuration in 24 ports with no additional CPU load. To reach this configuration, simply add additional Remora™ cards to any base card in the A200 Series. A single PCI or PCI Express slot hosts the connection and ensures common synchronous clocking for all channels. Like all the cards in the award-winning Sangoma AFT Series Product Line, the A200 and Remora™ system's architecture is shared with Sangoma's A101, A102, A104, and A108 cards, ensuring common 3.3 V or 5 V, high performance, universal PCI or PCI Express compatibility, and crash-proof field upgradable firmware to take advantage of enhancements, as soon they become available.