Slowing the master tape before recording vocals raises their pitch on playback — the trick behind Newcleus's cartoon voices

Newcleus’s famous high-pitched ‘wikki wikki’ cartoon voices on ‘Jam On It’ were made with a simple tape trick: they slowed down the master tape while recording the vocals, so at normal playback speed the voices played back faster and higher. This varispeed technique — record slow, play back at normal speed to pitch up (or the reverse to pitch down) — was a standard pre-digital way to shift pitch and formants together, producing the ‘chipmunk’ timbre. It is the analog ancestor of digital pitch-shifting.

Examples

Newcleus ‘Jam On It’: master tape slowed during vocal recording, so playback at normal speed yields the high cartoon voices. Reverse the trick (record fast, play slow) to get deep, monstrous voices.

Assessment

Explain why slowing the tape during recording makes a voice sound higher and faster on normal-speed playback. What happens to the formants (timbre), and what is the modern digital equivalent of this trick?