Monophonic Moderate

designating sound transmission or recording or reproduction over a single channel

"The old radio broadcast was monophonic, so all the music and voices came through on just one audio track without any stereo separation."

consisting of a single melodic line

"The old church organ was surprisingly monophonic, producing only a single clear melody without any accompanying harmony."

having a single channel; monaural (compare stereophonic)

"The old radio broadcast was strictly monophonic, so I couldn't enjoy the immersive sound of stereo speakers."