Although monitor engineering is often thought of as subordinate to handling the FOH sound, in reality it's at least as important.

To create a musical performance, two things have to happen: your audience needs to hear you, and you need to hear yourself. If you can't hear yourself clearly, how will you know that you're playing or singing well? In purely acoustic music, being able to hear oneself is often taken for granted. But there are situations where this doesn't happen as it should. For example, in an orchestra performing on stage, each musician needs to hear his or her own instrument clearly and distinctly from the other instruments around them. But sometimes the acoustics on stage make this difficult. Suddenly, one's ability to perform well has been diminished severely by the inability to hear one's own playing.

The same applies to amplified music. In the early days of pop and rock bands it was common to provide only front-of-house (FOH) amplification, commonly mixed from the stage by a member of the band (who, of course, couldn't hear the FOH PA properly). Although many exciting performances (and undoubtedly many distinctly unexciting ones) have been given in this way, the fact is that no-one is properly in control of what the audience hears. The one advantage is that the band can angle the speakers and set their levels so that they can hear themselves and each other reasonably well, most of the time.

Fortunately, progress has been made and we now recognise that it is essential to have the mix position at front-of-house, placed centrally amidst the audience area. The FOH engineer is now ideally placed to control the sound the audience hears. The problem now is that the band are no longer in any kind of control whatsoever of what they hear. Clearly, in an ideal scenario, there should be a completely independent system to provide the band with crystal clear sound so they can hear their own individual performances and the overall sound of the ensemble. This is what stage monitoring should provide.

Stage monitoring is taken very seriously by top professionals, and should be by anyone working in live performance, right down to pub gig or theatre foyer level. Good monitoring consists of having the right equipment, suitable for the nature of the venue and performance, setting it up well and, of course, operating it effectively.

Above all, musicians need to feel that they are making great sounds. If they feel that the performance is good, the performance will be good and the audience will go away whistling the tunes. Also, performers need to feel secure. Security comes from knowing what the other band members are doing, knowing where they are in the song, and being certain that the notes and rhythms they are playing fit in with the rest of the band.

So let's imagine you're the lead singer of a band. The lead singer needs to feel that his or her voice is strong, in tune, and communicating emotion to the audience. Clarity and good tone of voice are paramount. Also, the lead singer needs to hear the band, so that they know they are in tune and are fully comfortable that the band are following them precisely. If the band are playing to a click track or a recorded backing, strict tempo will be an issue and the lead singer may need the band to be more emphasised in the foldback, since now everyone has to follow the click (even though only the drummer would normally hear it) or recording; the band cannot follow the singer.

The other band members have their own individual requirements, but in general they also need to feel that they sound great. They need to hear the vocal, too, otherwise they might have a blank moment and forget whether they're in verse two or verse three (that's scary when it happens). They will also have a preference about which other instruments they need to hear most clearly, to feel as though they're 'gelling' with the rest of the band.