Amplification of quiet instruments such as guitar in an orchestral context is now standard. On the whole, however, orchestras have not used amplification as much as they might. It is ideal for correcting balance problems, especially in works which have relatively quiet instruments (such as most woodwinds) pitted against inherently loud instruments (such as brass). Whole amplified orchestras are relatively common, usually appearing at special events such as playing outdoors.
Processing sound can be done in numerous ways. These days most processing is done digitally, which means converting the sound from an analog to a digital signal. 'A to D' converters are built in to most computers and digital equipment. In practice, many digital signal processing effects mimic more traditional analog effects. So chorusing, delay, echo, flanging and added reverberation are all used frequently in both analog and digital domains. The same also applies to filtering, equalisation (EQ), compression, distortion, and frequency modification. The resulting modified signals are usually handled by a mixing desk, and with selective loudspeaker placement various images of the sound of the orchestra may be produced.
The Orchestra: A User's Manual is a free resource and will remain so. It still receives between 8,000 and 16,000 unique visits per month from all over the world. See the testimonials. Thanks to all the donations, I have been able to create this responsive re-design. But the movies and sound clips recorded in 2004 do show their age. I would really like to re-record everything and add many more techniques, especially for solo and ensemble writing. I estimate this will cost around £30,000. If you know a source of such funds, please contact me: a.hugill [at] bathspa.ac.uk