Reference: sndSuperpose
sndSuperpose(snd1, snd2) returns the sound obtained when superposing snd1 and snd2. snd1 and snd2 must have the same sample frequency.
sndSuperpose(snd1, snd2) returns the sound obtained when superposing snd1 and snd2. snd1 and snd2 must have the same sample frequency.