The Sound Guide a Non Technical Guide to Designing and Installing Simple Public Address and Sound Reinforcement Systems

THE SOUND GUIDE A NON TECHNICAL GUIDE TO DESIGNING AND INSTALLING SIMPLE PUBLIC ADDRESS AND SOUND REINFORCEMENT SYSTEMS THE SOUND GUIDE 1 2 CONTENTS Is it really that simple to install a Sound System? 4 Some Dos and Don’ts 5 What is a Sound System? 6 Components of a Sound System 8 Nature of Sound 11 Measurement of Sound 13 Loudspeaker Choice 14 Model Room 21 Acoustic Feedback 22 Induction Loop Systems 23 System Enhancement 24 Public Safety 26 Music Provision 27 Compact Disc Players 28 Radio Reception 29 Developing Your Needs 31 Applications 32 Conference, Lecture and Presentation Theatres 33 Churches, Schools and Community Halls 37 Swimming Pools 41 Shops, Bars and Restaurants 44 Offices 46 Sports Grounds 48 Application Examples 51 Hotel/Conference Facility 52 Church 54 Civic Centre 56 Swimming Pool and Leisure Centre 60 Superstore 62 Coffee Shop/Delicatessen 64 Professional Offices 66 Cricket Pavilion and Squash Court 68 Religious Studies Centre 70 3 IS IT REALLY THAT SIMPLE TO INSTALL A SOUND SYSTEM? Using this guide as a reference, together Often there is a mutual lack of with the instructions included with the understanding of what the sound system products to be used, the answer is ‘Yes’. is required to do. Most equipment suppliers have a The Sound Guide creates the opportunity technical helpline to answer specific for those with electrical wiring skills to planning or set-up questions. use this resource to install sound systems and suggests what should be acceptable The Sound Guide enables sound system standards of performance for a sound requirements to be defined and the system and its components. selection and location of key components – loudspeakers and microphones – to be Importantly, The Sound Guide is made. practical and, if followed, the experience of out team and “rule of thumb” Whilst many installed sound systems guidance will give excellent results. provide excellent results, performing exactly as the end user intended, Sophisticated technical planning exceptions indicate that the basic methods may suggest more accuracy; requirements of an installation are often however, this publication provides the exaggerated by the end user or the means for virtually anyone to design a potential installer, both allowing the basic sound system using the benefit of possibility of overpricing and expert knowledge for a wide range of unsatisfactory or even excessively applications. complicated solutions. Conversely, with a need to secure the order, many less caring installers offer unsuitable equipment which may prove expensive to own in the long term and might not provide exactly what is required. 4 SOME DOS AND DON’TS Some dos and don’ts on the safe DON’T leave the equipment switched on use of electrical equipment after a working day when it is As with any electrical equipment, care unattended. Using the on/off switch, must be taken if you are to obtain the disable the equipment and make sure best results and safety is to be assured. that more than one person knows how to do this. Special arrangements may need DO read the operating instructions to be made for people requiring special before you attempt to install and use any care. equipment. DON’T obstruct the ventilation of the DO ensure that all electrical connections equipment – with curtains or soft are properly made and in accordance furnishings for example. Overheating with the instructions. Switch off and will cause damage and shorten the life of withdraw the mains plug when making the equipment. or changing connections. DON’T allow electrical equipment to be DO consult qualified persons if you are in exposed to rain or moisture, or place any doubt about the installation, drinks on the equipment casing. operation or safety of electrical equipment. ABOVE ALL NEVER let anyone (especially children) push anything into holes, slots or any other opening into the equipment. NEVER guess or take chances with electrical equipment of any kind. IT IS BETTER TO BE SAFE THAN SORRY! 5 WHAT IS A SOUND SYSTEM? A sound system is simply that; a system person speaking can be seen and the which reproduces sound, mostly through purpose of the sound system is simply loudspeakers. Sound systems for public to reinforce his or her voice – such as in places are very different from those a church, at a public meeting or in the found in domestic environments. In the theatre. Sound reinforcement is also majority sound systems are not in stereo used to enhance the natural sound and generally they separate into two level so that the hard of hearing can main categories. participate. In most instances the person listening is seated, or standing a) Public Address in a relatively fixed position. Where the person speaking cannot be seen by the person listening – such as It is sometimes useful to install a in a railway station, airport, sports sound reinforcement system even stadium or a paging system in a factory when the building can be used without or office. The person listening is it so that less effort has to be made in invariably “on the move”, or working. order to be heard. Nevertheless, the primary function of any system which Wherever numbers of people have to also aims to reduce listening effort be informed, paged or simply must be to increase the level of useful addressed, there is the need for Public sound in such a way that the result is Address. as natural as possible.Naturalism is In an hotel, office, factory or shopping the desirable quality of a system; if centre or any of the previous examples, everyone in the audience can hear the ability to address will aid operating properly without being aware that a efficiency and may even, in the event of sound system is in use, then the an emergency, save lives. installation can be claimed to be successful. It will be the only way to speak to everyone at the same time, and just as It is also less stressful for any person with sound reinforcement, it is speaking over the system. They can important that the sound character relax in the knowledge that everyone and clarity is as natural as possible: a can hear without the need to speak fact that is determined by good above their normal level. planning, by the quality of equipment It may not always be possible to achieve used and the care taken in ensuring than all areas where the listener could be have adequate sound coverage. b) Sound Reinforcement Sound reinforcement, where the 6 WHAT IS A SOUND SYSTEM? continued the complete success of “natural” sound, What is a good sound system? especially for large audiences, but the A good sound system is one which equipment should be installed to be as satisfies completely the need of the unobtrusive as possible, to enhance this system user; it can be clearly heard possibility. Whilst architectural and where it should be and not where it aesthetic considerations are important shouldn't; it is easy to operate and uses they should not override those which selected products designed for long life relate to the fulfilment of the objectives and low cost of ownership. of the sound system. The first question to ask, when sound Helping the hard of hearing and reinforcement is being considered, is not the art gallery viewer “Is it necessary?” but “Will it help?”. In public address and sound Technically speaking there is little if any reinforcement installations it is usual to difference other than size and associated find an induction loop system installed to application factors, between Public assist the hearing aid user. The amplifier Address and Sound Reinforcement. The that is necessary to perform the equipment to provide either is functions of sound reinforcement and fundamentally the same. public address is identical but the The simplest sound system would amplifier for the induction loop is a comprise: specialised product. a) one microphone Induction loops are also used for the b) one amplifier transmission of commentary to persons c) one loudspeaker with normal hearing, for example in an In some cases such a system might be art gallery, museum or very noisy sufficient, however most good sound environments. Induction loop systems systems are usually larger than this, are fully explained on page 23. requiring more loudspeakers or microphones, for example. 7 COMPONENTS OF A SOUND SYSTEM What is a microphone? Some Hints on Usage A microphone is a device for converting 1. Under no circumstances tap or blow sound energy into electrical energy so into a microphone to test whether it is that this can then be amplified to working, after such treatment be sufficient power to drive a loudspeaker. surprised if it still does! A microphone has to be sensitive enough to respond Microphones are designed to provide to the minute amount of energy in different sensitivity patterns – the areas normal use; in comparison blowing where sound can be picked up by the into a microphone is the equivalent of microphones. These patterns can be: a blast from an extremely loud Omnidirectional explosion! “Hears” sounds from all around with equal efficiency. 2. For speech use, the microphone should generally be 20 to 30cm from the mouth, depending on local conditions. Closer microphone positions may have to be used to reduce the effect of higher than usual ambient noise. It is worth noting that Bidirectional reducing the distance between the “Hears” equally well in two opposite directions and this microphone and mouth by half can type of microphone is often reduce the ambient noise interference called a “figure of eight”. by up to four times. Remember that at this distance slight movements of the microphone will give relatively large changes in the sound output level from the sound system.

Load more