The output of Amplifier has a filter, which can inhibit the out-off-band harmonic waves and unwanted emission component.
放大器的输出接有滤波器,可有效抑制带外谐波和无用发射分量。
2
Sure, your friend can't sing on key and the bass buttons sticks, but the real problem, it seems, is your drums - terribly off-beat, and out of sync with the rest of the band.