Punch in/out

[1] The erasing and/or recording heads had to be very carefully aligned and applied to the tape surface with delicate timing and precision to avoid ruining the recording, and the practice was feared by most producers and engineers.

After the advent of 16- and 24-track equipment it was no longer necessary to risk the recording as a whole, as an empty portion of another track could be dedicated to such use.

Vocalists in particular would usually record several renditions over separate parallel tracks, with the producers choosing the best bits from the layered vocals to mix together.

In modern, digital audio workstation-based recording environments, punching in and out can be done automatically by pre-selecting the in and out points on the timeline of the DAW.

A more recent form of recording music, also dubbed "punching in" is the concept of creating a song by saying every bar rather than writing it down, while pausing to think of a next one to record until the entire song comes together, done in a similar fashion to freestyling.