In the 1980s, the introduction of electronic synthesizers, sequencers and prerecorded music tracks was initially greeted with fear by musicians' unions and performers.
However, rather than entirely replacing traditional orchestra pit instruments, these technologies are often used alongside the "live" violin players, wind instrumentalists, and rhythm section members.
As well, orchestral enhancement systems need to be able to make "live" adjustments to deal with forgotten lines or onstage mishaps, and transpose the key of the piece or its subsections.
Other modifications, such as the installation of acrylic glass screens, can be used to reduce the volume of loud instruments such as trumpets, cymbals, a drum set, or an electric guitar amplifier.
One of the problems with the use of standard public address systems in music theatre is that the front-of-house and monitor speakers may obstruct audience sight lines and interfere with the stage appearance.
In productions with little or no onstage set structures, such as a minimalist modern piece, sound engineers may opt to use higher-cost low-profile speakers, which are slimmer.
However, as concertgoers have become aware of the use of these systems, debates have arisen, because "...purists maintain that the natural acoustic sound of [Classical] voices [or] instruments in a given hall should not be altered.
There are many computer programs which are designed to take advantage of the MIDI (Musical Instrument Digital Interface) specifications to control multiple synthesizer parts.
The first Broadway musical to use a pre-recorded soundtrack with a few live musicians accompanying it was Priscilla, Queen of the Desert in May 2011; the producer claimed to be seeking a synthetic, cheesy sound.
Wind controllers can sense a musicians' embouchure, breath pressure, and other factors, and then this input can be "translated" by the synthesizer into the nuances that are expected in a traditional woodwind or brass instrument.