# Under development!

Sound is the most exciting part of the show - without it, you'd just be watching a silent movie! In StageSoc, the different types of shows will require different amounts of equipment and reinforcement. The highest tech shows may require amplification of the cast and band through the use of radio or wired microphones, whilst playing sound effects in time to the music and lighting cues, all whilst juggling additional equipment breakages mid-show with an audience cheering louder than you can make the speakers go. It may sound like living hell, but it really is very fun! Hopefully this page will break down the very basics of how sound works.

{ Sound source –> Microphone –> Mixer –> Amplifier –> Speaker }

Sound is generated by pressure fluctuations in the air, either by part of an instrument vibrating or a person's voice box. These pressure fluctuations travel through the air to the listener's ears, or in our case, to a microphone. The microphone's diaphragm vibrates, converting the acoustical pressure fluctuations to electrical voltage fluctuations that can travel down a cable. These voltage fluctuations are very small (in the region of a few millivolts) as there is very minimal energy in a sound wave.

Lots of different microphone signals are plugged into a device called a 'mixer', which combines all of the input signals into a set of outputs (e.g. to feed a speaker in the room). As the voltage fluctuations travelling down the cable are very quiet, they first need to be boosted around 100x by a device built into the mixer called a 'microphone pre-amplifier' (aka 'mic pre', 'pre-amp' or just simply 'the pre'). The mixer allows you to easily adjust the volumes of the individual microphones and they can also be edited e.g. to reduce the amount of bass or add effects.

The different outputs of the mixer can be sent to different places for different purposes, for example one pair of outputs may feed the main stereo speakers in the auditorium whilst another set sends a different feed to the band members in the pit or the green room next door. Although the voltage levels of these signals are much larger than those straight from the microphone (due to the pre-amp in the mixer), they are still not large enough to drive a speaker. The signals are therefore sent to a 'power amplifier', or just 'amp'. There are often multiple channels of amplification built into one box to save space - the most common are two or four channel amplifiers. Once the signal leaves the amp, it is powerful enough to be sent to the speakers. Some speakers have amplifiers built into them for ease of use, although these are often heavier than those without, and it can also be harder to change settings directly on the speaker if it is flown in the air. As such most of the speakers in The Annex are 'passive' (need a seperate amplifier) although there are a couple with the amplifiers built in (known as 'active speakers'). They each take different cable types so you can't accidently blow them up.

Sometimes, there will be another device between the mixer and the amps known as a 'DSP', or 'digital signal processor'. This allows more adjustments to be made to the signal than can be made at the mixer, as settings to make the speakers sound nicer in the room won't need to be changed between different shows and is therefore safer to have them seperate from the easily-editted settings on the mixer.