Acronym for Integrated Circuit.

This is the total opposition to the current flow of an Alternating Current (AC) within a measured system. Impedance is measured in Ohms.

Impedance Balancing (Load Balancing)
This is a technique applied to unbalanced signal outputs to minimise the effects of interference and hum by maximising the power contained in the signal.

Electronics component that is characterised by producing an increasing impedance with frequency.

Insert Point
This is a break point in the signal path that allows external devices to be connected in-line. Commonly these connections are used for connecting signal processors.

Unlike a song, an instrumental is a piece of music without any accompanying lyrics or vocal part. In popular music, an instrumental may include vocal sounds, but not lyrics.

A term used to describe any material that does not conduct electricity.

An interlude is a short sequence that often re-uses themes and feels from another section of the song. Literally, an interlude provides, when needed, breathing space between sections of the song. Interlude sections are almost always instrumental as they literally provide space for a singer to breathe.

Intermodulation Distortion
A type of distortion that results in the addition of frequencies, not present in the original signal. These are normally derived from the sum and difference products of the original signal frequencies.

Intonation is basically the alignment of the notes in relation to the position of the frets on the guitar neck. Adjusting the length of guitar strings affects the alignment of the notes in relation to the position of the frets so that they can be aligned. This is best done on a per string basis, with individual bridge positions for each string.

Introduction (Song)
Common features of an Introduction section:

  1. It sets the initial scene of the song and gives the listener their first idea of what is to come.
  2. It establishes rhythm, tempo, instrumentation, dynamics, beat, key and atmosphere.
  3. Major chords give the song an upbeat feel
  4. Minor chords will portray a sad feel or feeling of loss.
  5. Often the introduction is an instrumental, usually featuring a variation of the main theme.
  6. Drums and percussion parts are sometimes used on their own to strongly establish the rhythm or groove.
  7. It can build a sense of suspense and anticipation, creating a feeling of release when the song steps down into the verse.

Arrangement-wise, it isn’t uncommon to have the lead singer sing the main hook of the song at a slower tempo, or a variation on the main hook may be sung by backup singers. This seeds the main melody in the mind of the listener. This can evoke a stronger reaction to the melody proper when it appears.

In terms of chord progressions, introductions often:

  1. use one or more bars of the tonic chord
  2. Use a standard “turn around” progression for songs with a jazz or blues influence
  3. Use chord progressions from the verse, chorus, pre-chorus, bridge


Used to describe tape speed, this is an acronym for Inches Per Second.

As the word implies, in recording it is best to keep all of the recordings pure, insulating the rooms to eliminate bleed.