Welcome to the Individual Parts page of the Essential Audio Reference!

This is a very basic walk through the signal chain that precedes house sounds (or sounds from the PA heard in the venue).

The first stage is the actual microphone or sound source.

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This signal travels through the cable to the snake (or a sub-snake preceding it).

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The snake that runs to FOH contains all of the microphone or sound-source signals that need to go to the console (mixing board) to be synthesized.

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At the board (mixing console), all of the sound information coming from stage is mixed together; effects are added such as EQ-units, compressors/expanders, reverbs, delays, and others. This master signal (result of the synthesis of all channels) is sent (most typically) LCR (Left/Center/Right) back to stage. Sometimes an aux mix is used to customize the sub-woofer send, but…

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...Back at the other end of the snake, the LCR signal comes back to stage and is patched into the amp racks driving the main speakers/speaker arrays. At the top of many of these racks is what’s called a crossover. This machine appropriates signal in a designated manner to the different amplifiers in the rack so that the output of the amps can be sent in a number of different ways to the speaker arrays. Note: If the FOH engineer is also commanding the monitor mixes, these returns also travel back to stage, patch into a monitor amplifier rack, and the output of the monitor amps is dispersed in a custom manner throughout the stage. If there is a separate monitor engineer, there is usually a split at the main snake which runs identical signal to FOH and to the monitor console backstage. At that console, the process is very similar to house sound for stage, although not identical.

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The audience-address speakers vary quite a lot depending on the size of the venue, preference, weather and region, needs of the production, budget, and many other factors. They vary in power, power-handling, frequency-response, throw, clarity, quality, price, size, shape, number of cones/horns, passivity, and more.

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Additionally, there are a variety of ways to capture live sound on multi-track recording rigs. Many times a multi-track of a performance is used in combination with a variety of microphones placed strategically throughout the house to capture the “live” element and round out the sound of the recording. A variety of splitters can be used to achieve this, as well as making use of many digital boards’ ability to multi-track-out via Firewire, USB2.0+, or some other connection to a DAW (Digital Audio Workstation) or to a series of hard-drives. Just an example of one large aspect of live sound that I’ve had to skim over in my brevity.

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Be sure to play around with these concepts and discuss your ideas on our forum!

 

© Michael Fish (Contact)
Western Michigan University
1903 West Michigan Ave Kalamazoo, MI 49008.
Last updated:  4/23/13 13:47