acoustic bass

基本解释

Microphones, bass guitars, and electric-acoustic instruments, also typically have low-level outputs.
麦克风、电贝司（低音吉它）、和电子音响设备，特殊的也有低电平输出。
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The line arrays of FIGS. 10A and 10B include bass acoustic drivers 52 mounted in the same cabinet as the line arrays.
图10A和10B的线性阵列包括和线性阵列一样安装在同一箱体中的低音声学驱动器52。
Time after time, the strings build and build, sometimes soaring off into the ether, other times making way for a solitary bass line or acoustic rhythm.
弦乐一次又一次地加入其中，有时急速地升入太空，有时又让路给人声，自己甘愿作为低音声部或者原声节奏。

The acoustic bass is "probably just the most beautiful-sounding instrument, " the Philadelphian says.
NPR: Bassist Christian McBride, Plying the Bottom Groove
His latest album, The Toys of Men, functions as a career summary of sorts, with Clarke delivering a series of solo acoustic bass miniatures that reference past efforts while functioning with impressive restraint.
NPR: Stanley Clarke: A Lyrical Bass Player
We went from the original instrumentation of strings and a handful of winds to a rocking jazz rhythm section consisting of Hammond B3 organ, gospel piano, drums, electric guitar, Fender bass and acoustic bass, five saxophones, full brass, strings, timpani and percussion.
NPR: An Updated 'Messiah' from Marin Alsop