Don't expect any signal drop-outs as the Boss wireless system works in a 2.4 GHz frequency for great audio. Ultra-low latency also prevents a lag between playing and the amp producing the sound. The only difference between the WL-20 and the WL-20L is the lack of tone cable simulation, which is ideal anyway for acoustic guitars with a preamp on board, as the capacitance won't change the tone.
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