Sound Systems

Despite being a small haunt, Wolfstone features numerous sound systems. There is the large sound system that provides the overall soundscape for the haunt, and smaller localized systems that provide "spot sound" for assorted props.

This page contains a bit of introductory material, but largely serves as a jumping-off place for the other detailed web pages related to audio systems.

Large sound systems
Localized spot-sound
Assorted tips
Related Pages

Large sound systems

Our large audio system is built on the philosophy that there is an overriding sound theme that we want shared throughout the haunt. In the early days, this was the thunderstorm in our graveyard. Nowadays, several vendors sell "soundscape" atmosphere CDs that have a mix of sounds that make a good background. In the future, we intend to layer our overall haunt audio by mixing a commercial soundscape, the thunderstorm, and thunder on demand.

Once the overall sound track has been prepared, you feed it into a big amplifier, and pump it out to speakers all over the haunt.

With multiple speakers, you have to worry about speaker impedance matching. You can avoid a lot of trouble by using a 70-Volt speaker system or AirTunes speaker system.

Here's what we used for the main sound system, Halloween 2002.

There's a dual CD deck, by Gemini. The controls are at the top; CDs go in the lower part.

The mixer is from Radio Shack.

Down at the bottom is the Samson S-1000 amplifier.

We'll give a little more information on each type of component...

CD Players

We gave up on tapes long ago. Now, all of our sounds are either recorded on CD, or in solid state storage.

The main sound for our haunt consists of two layers: storm sounds that form the background, and a soft overlay of some music. We don't put them on the same disk. Each one is a CD, playing side-by-side. Then we mix the two sound tracks together.

We could use two different CD players, but we picked up a dual player that does a nice job.

This is a nice dual CD player aimed at the DJ market. The unit is built in two pieces, one for the controls, the other for the disc drives.

It mounts in a 19-inch rack.

Mixer

The mixer takes several audio sources and merges them together to make a single sound track.

There are monophonic mixers that accept input from microphones, and stereo mixers that carry two discreet channels for each source.

This is a small stand-alone stereo mixer from RadioShack.

This is a larger stand-alone stereo mixer from RadioShack. It mounts in a 19-inch rack.

Amplifier

The amplifier takes the mixed sound track and cranks it up to feed to the speakers.

This is a small stereo "public address" amplifier from RadioShack. It mounts in a 19-inch rack.

This is a powerful, high-quality amplifier. 500 Watts stereo, or 1000 Watts bridged mono.

It mounts in a 19-inch rack.

Localized spot-sound

We have found that a satisfactory prop can really kick butt if you add an individual sound to it. We first discovered this with the giant spider: it was nice the first year, but it was really scary when it made noise.

As a result, most of our props have their own mini sound track. They aren't necessarily very loud, because they are local to the effect. Each one uses a dedicated set of amplified speakers so that the sound can be "aimed", and that sound levels can be set for each prop.

So, where does the sound come from? Our "startle" scares tend to use a scream box. Others, like the spider, use a generic recordable sound box with a special track recorded just for that prop. Still others use an inexpensive CD player, like our use of the Terror Tone.

One of our most popular displays in 2001 was a skeleton who sat propped against a tombstone, quietly reciting some of the most famous speech of the 20th century. Adults would stand around for 10 or 15 minutes at a time, listening to the skeleton deliver Babe Ruth's farewell to baseball and Martin Luther King's "I have a dream" speech.

This Audiologic portable CD player was purchased at Fry's for $20 (September 1999).

We bought four of them for spot sound in various locations.

Assorted tips

Assorted tips that may be of assistance to large and small audio systems...

Clipping Is Evil

Perhaps the worst thing you can do to your sound system is crank it all the way up, which usually causes "clipping".

Let's say that the input signal is 4 Volts and your amplifier is multiplying the voltage by 3x. The output signal will be 12 Volts (4x3).

Let's say that this is an automotive system, and you have 12 or 13 Volts to work with. You can get the 12 Volts you need to properly amplify the input signal.

Now, take the same 4 Volt input signal and crank up your amplifier to multiply the voltage by 4x. The output signal should be 16 Volts (4x4).

But you only have 12 or 13 Volts to work with. So the amplifier does the best it can, putting out the most voltage it has.

The pink lines represent the available voltage, so the red tips of the signal are "clipped" down to the available voltage level.

When clipping happens, the output won't sound right, because your output is not a faithful (amplified) copy of the input signal. But it gets worse...

The tips of the signal are no longer rounded. Where the signal is clipped, the signal becomes more square, with sharp edges. This causes harmonics, which further distort the sound and can damage speakers.

Some amplifiers have a light on them that flashes when clipping occurs. Watch out for that indicator and turn the volume down if it lights frequently.

Remote Volume Control

We had a sound track that we wanted to turn up and down remotely, via X-10. So we built a remote volume control.

Use closed-circuit jack when tapping output

One of the handy haunt hacks is to take a commercial gadget that makes noise, and tap the output for use in other things. For example, you might hook into a "Thunder Staff" and use it as a source of sound effects for a storm.

The simplest way to do this is to completely replace the speaker that is already inside the gadget. We suggest instead that you make the internal speaker optional.

A closed-circuit jack lets you do this; it has a switch built into it. When nothing is plugged in, the signal goes to the internal speaker. When you plug in something else, the internal speaker is disconnected. Many portable radios do this: play through the internal speaker, or plug in earphones and the speaker cuts off.

This means that your modified gadget is now a reusable component. You can use it as a sound module, or in its original configuration, simply by unplugging it.

You may be interested in these related pages:

Thank you for visiting. Your comments are welcome.
. . . . . .