How to Connect Audio to Your Public Address System by AudioConexus Inc.

PUBLIC ADDRESS SYSTEM INTEGRATION

What You Need to Know

PUBLIC ADDRESS SYSTEM INTEGRATION WHAT YOU NEED TO KNOW

If you've ever stood over a Public Address System with connections and wires and didn't know where to begin - this guide is for you. This guide is designed to assist you in connecting our commentary systems to your PA Systems. With many organizations coming to us for assistance with PA System integration, we quickly realized there was a need for more information regarding how to identify and solve audio problems with PA Systems. This guide summarizes two methods of integration. While we do not sell PA Systems, we're hoping this guide will assist you. Thank you for downloading our guide. If there's anything you'd like to see changed or added please let us know. We’ll do our best to expand on these topics whenever possible (for everyone). Reader’s Note: Any paragraph text that appears as “bold” (i.e. mixers) is defined in the Glossary of Terms on page 12.

WORKING WITH PA SYSTEMS Integration of AudioConexus GPS commentary systems with PA systems of various brands can often be a confusing ordeal. This guide is designed to give you a basic understanding of sound levels, connectors, equipment, and how they all work together. When connecting our GPS commentary systems to your Public Address Systems, this is what you need to know.

SOUND OUTPUTS

GPS commentary systems, Public Address systems (“PA Systems”), speakers, microphones and other audio accessories like mixers all play a role in delivering sound to your passengers. To better understand what sound output levels mean, let’s begin by describing “sound output”.

Sound Output Levels In Audio Electronics, there are generally three “levels” of sound. These are separated by voltage and wattage (voltage x amperage). The three levels of sound are: Speaker Level Speaker Level sound is typically delivered from 3V - 18V and is a higher wattage sound level. This is a powerful signal that can run headsets, speakers and other listening devices with ease. Line Level Line Level sound is typically delivered as a 1V - 3V signal and is a low wattage level. This is not normally powerful enough to 3

power a speaker at a decent sound level. This is used for low-wattage sound transfer from device to device. For example, this can go from a DVD player to a mixer or directly to a PA System input. Microphone Level Microphone Level sound is typically in the 50mV – 250mV range. This is a very low wattage signal used for microphone connections. Matching Levels Plugging any “level” of signal into a similar “level” (for example: speaker level into speaker level) will work as intended. But if you’re trying to connect mis-matched signal levels you will run into a roadblock - terrible sound. The expected “level” of any connection may or may not be evident on a device. Many connections or “inputs” are labelled “AUX” or “AUDIO IN”. In these cases, please consult the user manual of your device, normally addressed in the “Technical Specifications” page of your user manual. Below is a chart to illustrate the issues that you may encounter when matching audio levels. Please take note of which is the “output” and which is the “input”. Microphone Level

Line Level

Speaker Level

Microphone Level Line Level Speaker Level

OUTPUTS

INPUTS

Volume Too Low

Volume Extremely Low

Volume Too High

Volume Too Low

Volume Extremely High

Volume Too High

“Matching” the voltage output and input of an audio device is extremely important. In addition to the above, putting a very high voltage output (Speaker Level) into a lower voltage input (Line level or Microphone level) can result in audio problems such as crackling, distortion or damage to audio system components. This happens because you are using an already pre-amplified (line level) or amplified (Speaker level) signal and are connecting it to an input that will attempt to amplify the audio signal further. This creates sound quality problems described in the chart above. To better understand inputs and outputs let’s review the physical connections required to connect a commentary system to a PA System. These physical connections are known as plugs and jacks. Plugs and Jacks As well as considering the electronic side of PA system integration, let’s review the physical side of installations. You need to be aware of plugs and jacks when buying an adaptor cable for your system. An adaptor cable is any cable that has two different style ends. A 3.5mm male to 2x RCA males is a commonly used adaptor cable. Many plugs are used throughout the world, and even two identi 4

some examples of what these connectors look like:

Connectors by Sound Levels and Output Voltage Speaker Level (∾12V)

3.5mm male to 2 x RCA cable cal looking plugs can have a different “pin configuration” – they can be wired differently and not behave the same. A 3.5mm male jack, (refer to the diagram below) also known as a headphone or earbud jack, is a commonly used connector in consumer electronics. This jack is designed by companies in different ways and can feature a different number of connectors or “rings” as depicted below. Always be aware of adaptor cables that claim to be “for iPhone” or “for Nokia”. Only use these cables if you are using the appropriate product. These jacks have unique configurations.

Line Level (1 - 6V)

Microphone Level (<350mV) Just like the 3.5mm male jack above, there are several connectors available on the market today designed for different uses. Remember when we said that in audio electronics, there are generally three “levels” of sound. The three levels of sound are speaker level, line level and microphone level. Connectors often differ depending on the connection points to your PA systems. Here are 5

COMPONENTS

Sources, Mixers and Amplifiers In the world of stereo there are going to be three main components to sound processing. These are Sources, Amplifiers and Mixers. Sources Sources are the items from which sound is generated. This can be a number of devices, such as DVD players, mobile phones, radios or MP3 devices. Each of these units is made differently because they each serve a different purpose. For example, a source such as a car stereo can also have an amplifier built-in to power attached speakers. Sources can output all of the “Voltage Levels” listed in our examples on the previous page. What “Voltage Levels” a Source such as a DVD player outputs is normally documented in a user manual or is printed on the unit itself.

Amplifiers

Other Components and Features

Amplifiers are devices made to amplify, or increase one voltage of audio into another. Common amplifiers will have line level and sometimes microphone inputs. The Outputs of an amplifier are normally speaker level. The most common amplifiers use phono (RCA) plugs for inputs and hard wire terminals that use ring terminals for outputs. The outputs of an amplifier are normally connected directly to a combination of vehicle speakers. Occasionally an amplifier will have a ”gain” knob. This is used to more accurately match the output voltage of the source to the maximum input voltage of an amplifier. This is not a volume control. Amplifiers require more energy to function than sources and mixers, which generates more heat. For this reason, amplifiers normally have a large “heat sink” to help dissipate the heat.

There is a large variety of options available on the market to do nearly anything you wish with an audio system. In addition to individual components, many manufacturers have been trying to combine individual components into new devices with a host of features.

Audio Mixers Mixers are devices used to manipulate different audio sources that are to be played out of a single speaker system. Mixers normally operate on Line level inputs and also have a line level output. Part of the job of a mixer is to use “gain” controls to make sure that all of the connected devices play out of the output at the appropriate line level voltage. This ensures that a device with a higher line level voltage will not overpower a device with a lower line level voltage, making the lower voltage device inaudible. Again, gain controls are not to be used as ‘volume’ controls’. Adjusting the gain too high for the appropriate device can cause bad sound quality, distortion and audio component damage.

As the perfect example of this, you can take something very common, being a car stereo. If you break a basic car stereo down into its’ individual components, you will typically get a list that is similar to the following: • Radio • CD Player • Satellite radio player • MP3 player • Equalizer • Source Selector • Mixer • Amplifier Many units are very multi-functional and so it is important to know how each source component will be used as part of your larger system. There are a multitude of combinations so we list some of the features that are prominent within automotive sound systems today and what they do in brief. Since we’ve covered sources like amplifiers and mixers, let’s look at Equalizers, Duckers, Attenuators or Level Converters, and Signal Processors. Equalizers Equalizers are made to manipulate different frequencies of sound on an individual basis. This enables compensation for some of the environmental challenges that sound frequencies face 7

such as “bad quality of sound” as perceived by a listener. Duckers Audio ducking is a feature used when multiple sounds or audio sources are present. This allows one sound to be partially or fully muted while another sound is playing. The use of Audio Duckers is common in the installation of Public Address Systems. Audio Duckers allow you to prioritize which sounds are heard first. For example, a driver’s microphone takes priority over audio commentary because the microphone is used for emergency purposes. Attenuators or Level Converters Attenuators and level converters are used in the opposite way of an amplifier. Where an amplifier increases the voltage level, attenuators and level converters decrease the voltage level. These are of use when you wish to place a high level output into a low or microphone level input. Attenuators and level converters will have a descriptor of what “levels” can be input and output. It will often label what you should expect in terms of a Decibel (dB) decrease. The higher the number, the lower the sound output will become.

How Are They Connected? In a standard installation, audio sources generate sound and send an audio signal to the mixer. The mixer then regulates the voltage across multiple sources, to make sure none are too loud or too soft. The sound then travels from the mixer to the amplifier and finally to the speakers. This is depicted in the example below.

DVD PLAYER

RADIO

MIXER

AMPLIFIER

SPEAKERS

(Decibel (dB) refers to a level of loudness. For example, “his voice went up several decibels”). Signal Processors Signal processors are used in an attempt to increase the audio quality of sound put through the machine. These often attempt to get rid of unwanted noises or static. These can also attempt to compensate for some environmental effects as well as speaker timing effects.

HOW TO

How to Connect TourMaster to your Audio System The AudioConexus TourMaster, TriggerPOINT and single language (TourMaster Lite) GPS commentary systems can be connected to your audio or PA system using one of two methods. The main difference between the two methods is how you would like your driver to change the language played over your PA system. Using the first method, the driver must use the options menu on the Driver Control Panel to change the language that is played over your PA system. What this means is, your driver will also have access to other features available on the system such as saving new GPS waypoints or enabling chimes to alert passengers commentary is about to begin (to name a few). In the Second Method, a driver can use an Audio Controller or Wireless Receiver to change the channel to the required language or sightseeing topic just like the passengers with headsets or earbuds can.

This means your driver will not have access to the hidden features available on the Driver Control Panel. Method One: Line Level Audio The first method of connecting a TourMaster system’s sound to your PA system is to use the line level audio out on the rear of the TourMaster unit (the audio source). This will need to connect to a line level input on your mixer or stereo head.

Please keep in mind: • This method requires the volume to be controlled by your PA system • The driver must enter the options menu in the Driver Control Panel to change the tour language. This requires driver training.

This requires: • A working mixer or; • A working stereo head unit with a line level input; • An RCA cable or; • An adaptor cable from RCA to the needed input plug. Method One, Figure 1

TOURMASTER HEAD END

RCA cable

STEREO HEAD OR MIXER 10

Method Two: Driver Audio Controller

Please keep in mind:

The second method of putting a TourMaster system sound through your PA System is to have an additional audio controller and hub installed for a driver. The audio controller plays speaker level sound. This means it will need a speaker level input on your mixer or stereo head or a Line Level Converter between the driver’s audio controller output and a line level input on your mixer or stereo head.

This method has two places to control the volume.

This requires: • A working mixer or stereo head with a speaker level input or; • A line level converter and a working mixer or stereo head with a line level input available; • An adapter cable from a 3.5mm male to the needed input plug type (i.e. RCA, 1/4”, XLR).

DRIVER AUDIO CONTROLLER 3.5mm male cable

2. The second method is the volume control of a PA System. • A driver can change the language or topic played over a PA System using the audio controller. This requires less training and a lower possibility of accidentally changing other options available on the Driver Control Panel. • If no stereo level input is found, you will need a line level converter to properly connect to an available line level input. You can purchase a RCA Line Level Converter from AudioConexus. PLEASE NOTE: Some PA System manufacturers do not supply PA Systems with industry standard cable inputs and outputs. Prior to connecting a GPS Commentary System to your PA System, please verify your component input and cable type.

3.5mm male

RCA cable Line Level Converter

1. The first method is the volume control available on the audio controller.

If a manufacturer’s proprietary cable is required, please ensure you have the cables necessary to connect an additional audio source to your PA System.

RCA male

STEREO HEAD OR MIXER 11

Glossary of Terms

connected to an AUX port or other medium such as a vehicle’s audio jack.

Amplifier Distortion An amplifier, or (informally) amp is an electronic device that increases the power of a signal. Attenuator An attenuator is an electronic device that reduces the power of a signal without appreciably distorting its waveform. An attenuator is effectively the opposite of an amplifier, though the two work by different methods. While an amplifier provides gain, an attenuator provides loss, or gain less than 1. Audio Controller An electronic device that provides individual passengers with the ability to increase or decrease volume levels or change the language and/or topic of a sightseeing audio tour. Audio controllers are typically located on a wall or a seat back of a bus, boat or train. AUDIO IN An input jack which delivers a signal to piece of equipment or a jack that receives a signal using a cable with the proper connectors. AUX An auxiliary port (AUX) is the logical name for a standard communications port. AUX is an asynchronous serial port with an interface that allows the auxiliary input of audio signals for MP3 players, headphones, portable music players, amplifiers and speakers. The AUX port is typically used for audio equipment that receives peripheral sound sources, such as digital music players or audio speakers. The peripheral sound device is

Unwanted distortion is caused by a signal which is "too strong". If an audio signal level is too high for a particular component to cope with, then parts of the signal will be lost. This results in the rasping distorted sound. Driver Control Panel The Driver Control Panel is a standard piece of peripheral equipment supplied with the TourMaster, TourMaster Lite and TriggerPOINT GPS commentary systems. The Driver Control Panel is used for manual operation of audio commentary and includes several options for “system” settings. The Driver Control Panel is typically installed within reach of a driver, captain or guide. Duckers In ducking, the level of one audio signal is reduced by the presence of another signal. On a bus, this can typically be achieved by lowering (ducking) the volume of a secondary audio source such as audio commentary when the primary source starts (a microphone for example), and lifting the volume again when the primary source is finished. Equalizer The process of adjusting the balance between frequency components within an electronic signal. The most well known use of equalization is in sound recording and reproduction but there are many other applications in electronics and telecommunications. The circuit or equipment used to achieve equalization is called an equalizer. 12

These devices strengthen (boost) or weaken (cut) the energy of specific frequency bands.

signals, primarily audio. It is cylindrical in shape, typically with two, three or four contacts.

Gain

Modern phone connectors (jacks) are available in three standard sizes: 1⁄4 in (6.35 mm), 3.5 mm, and 2.5 mm sizes. The 3.5 mm and 2.5 mm sizes are also referred to as 1⁄8 in and 3⁄32 in respectively in the United States, though those dimensions are only approximations. All three sizes are now readily available in two-conductor (unbalanced mono) and three-conductor (balanced mono or unbalanced stereo) versions.

In electronics, gain is a measure of the ability of a circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output by adding energy converted from some power supply to the signal. It is usually defined as the mean ratio of the signal output of a system to the signal input of the same system. GPS Commentary System An electronic audio system that delivers audio commentary to passengers at predefined geographic locations. Audio commentary is delivered to hardwired audio controllers and wireless receivers and heard by passengers using listening accessories such as earbuds and headsets. Audio is also optionally delivered to PA Systems. In the case of PA Systems, audio is heard by passengers through speakers. Hub A Hub, a small box, works with a hardwired GPS commentary system to allow you to connect audio controllers to a hub which leads to the head end system (also known as the commentary system). Input A place where, or a device through which, energy or information enters a system. Jack

Line Level Line level is the specified strength of an audio signal used to transmit analog sound between audio components such as CD and DVD players, TVs, audio amplifiers, and mixing consoles. Line Level Converter A Line Level Converter is used to either convert voltage from high-to-low or low-to-high. This peripheral device is used to match mismatched voltage levels. Manufacturer’s Proprietary Cable A proprietary cable is one that only works on one type of device. It's a cable that works with one thing and one thing only. A regular cable, like a RCA cable, will work on a large variety of devices. Microphone Level A term for the amount of signal that comes out of a microphone.

In electronics, a phone connector (jack) is a common family of connector typically used for analog

Mixer

TourMaster Lite

In professional audio, an audio mixer is an electronic device for combining, routing, and changing the level, timbre and/or dynamics of audio signals.

TourMaster Lite is a GPS commentary system designed to deliver one tour over a PA Systemâ&#x20AC;&#x2122;s speakers.

Output A place where power or information leaves a system. Signal Processors Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations on or analysis of analog as well as digitized signals, representing time-varying or spatially varying physical quantities. Sources Devices in a system that provide audio-only playback, such as CD players, AM/FM tuners, satellite radio tuners, DVD players, and GPS commentary systems.

TriggerPOINT TriggerPOINT is a portable, wireless multilingual, multi-topical GPS commentary system that uses Radio Frequency to distribute multiple audio tours to passengers based on their language and/or topic preferences. Audio is delivered to wireless receivers connected to listening accessories such as earbuds or headsets. Wireless Receiver A device that is used by people to listen to an audio tour. People select their language and/or topic using the device. Listening accessories such as earbuds or headsets are worn. Using wireless receivers, people are not restricted to seats to listen to audio commentaries.

Speaker Level Taken from the speaker terminals. This signal has already been amplified. TourMaster TourMaster is a hardwired multilingual, multitopical GPS commentary system that uses hubs and audio controllers to distribute multiple audio tours to passengers based on their language and/or topic preferences. Audio is delivered to audio controllers connected to listening accessories such as earbuds or headsets.

CONTACT AUDIOCONEXUS

If you have any questions regarding PA System integration, please call us. Weâ&#x20AC;&#x2122;re here to help. Technical Support (613) 507-1300 or email our Technical Support Team: support@audioconexus.com