Alesis M1 Active 320 USB | Full-Range Studio Monitor Desktop Speakers with Bass Boost (Pair) Stereo monitors with integrated USB audio interface; 3-inch woofer and 1-inch tweeter 16-Bit / 44.1-48kHz recording and playback Features stereo 1/8-inch (3.5mm), RCA and 1/4-inch (6.3mm) inputs Includes a front-mounted 1/8-inch stereo headphone output, switchable power supply Full, rich acoustics with a frequency response up to 20kHz