class A push-pull sound track

class A push-pull sound track

[‚klas ′ā ¦pu̇sh ¦pu̇l ′sau̇n ‚trak]
(engineering acoustics)
Two single photographic sound tracks side by side, the transmission of one being 180° out of phase with the transmission of the other; both positive and negative halves of the sound wave are linearly recorded on each of the two tracks.