soundboard

Short definition from Wiktionary

Noun

1. 1
   A wide, flat board placed within, or forming part of the body of, a musical instrument in order to improve vibrations and increase volume.
2. 2
   A mixing console used to combine and blend different audio sources to a single output.
3. 3
   A sounding board.
4. 4
   A control panel offering playback of various sound effects.