The Laptop SoundPort^TM (Model LSP-2) is a compact adapter that plugs into a laptop computer speaker jack, changes the output to balanced mic-level signals and mates with standard XLR audio cables for connections to a house audio system. A ground lift switch assures a hum-free interface. On-board volume control. This is a stereo version of the LSP-1. Separate volume controls for each channel and a sum switch to combine them into one mono signal. Includes alternative USB sound capture from computer for clearer signal. No drivers required for Windows 7 and XP. Stereo headphone monitor loop-through and output mute switch. USB mini cable and carry pouch.