As soon as we erected the felt barrier between the speakers, I discovered that it absorbed high frequencies and dimmed the vibrancy of treble sounds. (the felt had no effect on mid and lower range).

当我们立了感觉障碍的发言后，我发现它吸收了高频率和变暗活力充沛的高音音色。(觉得没有影响中和下限范围)。

youdao

Tri-Amping - A technique commonly used in large-scale sound amplification for concerts, Tri-amping is the practice of connecting three audio amplifiers to a loudspeaker unit: one to power the bass driver (woofer), one to power the mid-range and the third to power the treble driver (tweeter).

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