The D San LSP-3 is a passive direct box; you may think of it as an "extension cord" for your crowded audio mixer. It provides 1/8" and 1/4" stereo TRS jacks to accept headphone-level computer or instrument audio with loop out RCA phono; 1/4" TRS mono jacks to accept low-level signals from instruments or media players; and an 1/8" stereo plug to capture headphone audio from computers, cell phones or media players.
There is volume control, and a selector switch for L, R or L+R combined channels and a ground lift switch. (When lifting the ground connection, be sure that input and output devices are themselves grounded.). The LSP-3 has balanced mic-level output on duplicated XLR male jacks.
The LSP is supplied with zippered storage pouch large enough to accommodate the 6-foot pigtail cable.
Note: LSP-3 is not a mixer. Although multiple audio sources can be connected simultaneously, it is intended to handle one active source at a time.