Technical Architecture

WASAPI Loopback

A Windows audio interface that captures all system audio output directly from the sound card without microphone input.

Windows Audio Session API (WASAPI) loopback capture is a low-level audio interface that intercepts all audio being played through the system's output device. Unlike microphone-based capture, loopback recording captures the exact digital audio stream — including remote participants in video calls — with zero quality loss, no echo, and no background noise. This technology is what enables desktop-native transcription tools to capture meeting audio without joining the call as a bot. It hears exactly what you hear through your speakers or headphones, providing superior audio quality compared to microphone-based tools.

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