Lexicon Alpha - Perfect for Linux

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I chose it after checking online that it worked seamlessly under Linux. The other reason for my choice is that the control elements seem very well thought-out: - Two volume knobs, with peak indicator for the Line 1/Instrument and Line 2/Mic inputs - A switch to toggle between mono and stereo listening of the inputs - A button to mix the input/output volume. I use it to play guitar, connecting my Tech 21 Blonde into one of the line inputs.