Why Use Soundfield Systems in Schools?

Introduction

Students must be able to hear the educator’s voice clearly in class, in any environment whether it is in a classroom, laboratory, and library, study, work area or science room. This is not always possible. With building standards in every school being different, or even variable on the same campus, ensuring the proper acoustics can be difficult.

Learning environments must support the needs of all who teach and learn in them including those who find learning difficult or who have deficits such as auditory processing disorders, ASD, ADHD, auditory processing disorders, partly deaf or loss of hearing.

A number of factors preclude optimum hearing. Factors include: 

• Size or the dimensions of the room or space
• Classroom working noise
• External or peripheral noise
• The distance between teacher and students
• Poorly designed classroom acoustics 
• Buildings built over a hundred years ago
• Portable classrooms next to busy, noisy roads

Can make understanding the teacher difficult, even for children with normal hearing. It also impacts upon anyone speaking, including other students responding to requests, offering opinions or answering questions. This may be in whole class participation or whilst working in large or small groups.

Noisy or busy classrooms often force the teacher or trainer to raise his or her voice in order to be heard. This usually leads to vocal hoarseness, pain and in the case of temporary voice loss, time off work. The teacher, instructor or trainer cannot reliably convey information accurately and many students suffer the consequences. The educator can be frustrated as students do not adequately hear or follow directions or instructions. This may cause confusion, misdirection and therefore behaviour issues arise. Some students become disengaged and disenfranchised.

Soundfield technology was created to alleviate these issues and to improve sound quality with clarity, not just amplification. It does this by distribution of voice with low-level amplification. In the case of additional support for students with hearing loss who use a personal FM, the soundfield system enables access to several sound sources without having to juggle connecting between devices. For example a teacher’s speech, peer speech and an IWB are automatically coordinated.

Soundfield systems, of which there are many competing companies and models, clearly amplify the teacher’s (or speaker’s) voice. It aids in assisting students to hear and understand directions more easily. The benefits include improved student performance, better communication, less overall noise and increased student participation. It definitely supports students with hearing loss as they can use their aids and assistive technologies in conjunction with Soundfield systems. Some systems are portable while others are fixed permanently or semi-permanently to a wall or fixture.

All students can benefit from having this technology in a learning space, classroom or other environment. 

?       Students listen and learn skills more effectively

?       Less speaker repetition is required

?       Enhanced class instruction and management is made possible

?       Less teacher vocal strain

?       Other participants and students can also use the system (using two microphones)

?       Other audio content (e.g. from an iPod, iPad or computer) can be optimised

?       Some Soundfield models provide Podcasting options built-in or as an add-on

Effective teaching and learning areas and environments require optimum acoustic value to facilitate learning. There are three main considerations when investigating how acoustic value is measured. These include:

?       Acoustic value

?       Hearing access

?       Speech intelligibility 

Each entity has an individual impact on learning outcomes and they all differ, yet are crucial in realising optimum results. 

Understanding how to achieve optimum speech intelligibility in the learning space is critical in today’s classrooms where audio and visual information is used extensively. It adds value to the learning and provides the reassurance to educators, parents and students in classrooms and other learning environments will enhance learning outcomes in an engaging and interactive way.

• Speech Intelligibility- This refers to maintaining acoustic access to speech with a high degree of clarity in the presence of peripheral and background noise. Amplification together with clarity achieves speech intelligibility. Soundfield Technologies lift the speaking voice over and above background noise, without over amplification. Public Address systems can just amplify all sounds and therefore do not resolve this issue, but merely compound it. Other computer sounds, music and information from other sources suffer similar fates.
•  Acoustic Value. This refers to the ability of the room, environment or space to soften and absorb sound. Optimum acoustic value includes rooms and areas that dampen reverberation in the presence of noise.  Furniture, surfaces, doors, furnishing and windows impact upon how well the space reflects acoustic value. Improved acoustic value assists access to speech but does not necessarily improve or impact upon speech intelligibility. 
• Hearing Access. This refers to the addition of technologies to a space that support the needs of hearing impaired students or participants. These technologies include Hearing Aid Induction Loops and Radio Frequency (RF) hearing assistance systems. They directly cater to users with hearing loss and are usually specific to their needs. Soundfield systems create a platform for increased hearing access.

What is Soundfield?

The Soundfield microphone is an audio microphone composed of four closely spaced sub-cardioid or cardioid (i.e. unidirectional) microphone capsules arranged in a tetrahedron. Michael Gerzon and Peter Craven invented it at Calrec Audio Limited, who launched the first soundfield microphone in 1978, developed their theoretical design into a practical microphone system.

In 1993, the Soundfield microphone part of Calrec was separated out as the company SoundField Limited. This new venture further developed the range of products. After the original patents relating to the Soundfield mic expired, other companies started to manufacture them together with various new designs, accessories and units.

Suffice to say, a Soundfield System can function as a mono microphone, a stereo microphone or as a surround sound microphone. High end users include Engineers, Sound and Recording Studios, Broadcast units, Television Stations, Opera and Concert halls, Orchestras, Live Music, Film Production as well as Education and Further Training.

The Redcat Lightspeed   

Recently I have been using a portable Lightspeed system from Redcat manufacturers. It is a panel that can be permanently fixed to a wall or fixture in a classroom or placed on a shelf, serving as a portable unit. It can be quickly set up in any learning space and is extremely straightforward. 

The Lightspeed has a series of exciters that apply sound energy directly to the REDCAT sound panel, thereby exciting the voice signal. Energy from the exciters is transferred to the sound panel surface, and every point across the surface radiates the sound. This is how it can send and disperse sound evenly throughout the classroom or learning space. The exciter technology helps students hear the critical higher frequencies of their instructor’s, trainer’s or teacher’s voice.

In the Lightspeed panel are four traditional cone speakers placed strategically. It easily fills the room with sound. Users can also use two cone speakers and turn up the volume a little more and audibility will still be more than satisfactory. 

How to Use the Redcat Lightspeed

Locate and plug in the AC cord into power, connect to the Lightspeed AC/DC switching adapter and then connect to the bottom right hand side DC input on the black Lightspeed panel. Then press the On/Off button directly above it. A Blue status light appears on the front right hand side of the panel.

A Redmike hand-held microphone, (with a lanyard to place over the user’s head) is supplied. The user turns it on (pressing a small discreet Power button at the top left hand side), a Blue status light displays at the front of the unit. The Channel ‘A’ red status light displays on the Lightspeed panel. 

Now the user simply speaks into the microphone. It’s that easy. The Channel B can be used with a second microphone or an Infrared Media Connector. 

Another input is also available on the Lightspeed panel itself (on the right hand side panel). Any device with a 3.5mm jack connector can be plugged in. Ideally, this might be a computing system or Tablet used with a projection system, Interactive Whiteboard or Interactive TV. A Tone and Audio In knobs control minimum and maximum setting control.

Below the Audio In is the Audio Out. Once again, any device that has a 3.5mm connector can be used, most particularly RF 

The Infrared Media Connector (iRMC) unit can be powered with an AC adaptor (supplied) or plugged into a device that has USB power (e.g. a desktop computer, Netbook, Notebook, MacBook or other suitable technology. It has three inputs. The standard connection is a 3.5mm plug. These five connectors are all located on the right hand side of this lightweight unit. On the other side a Power button and a knob for increasing and decreasing volume are located. When it is turned on, an amber status light displays, and when used (with audio from a computer, iPad, iPod or Smartphone) it turns blue.

This very useful unit transmits a signal from any number of devices in a classroom, laboratory or lecture theatre, including:

·      Television broadcasts, cable or satellite TV  

·      CD, DVD or Blue Ray players

·      Boomboxes or portable radios and CD players

·      MP3 devices and players

·      Desktop computers, laptops, Notebooks as well as portable MAC iOS devices

·      iPads or Mini iPads

·      iPods and iPhones

·      Android tablets and Smartphones

·      MS Windows, Surface or other operating system tablets, devices and Smartphones

·      Hand held video cameras, Camcorders or digital cameras (with audio)

·      Digital Audio Recorders

·      Other branded lapel, desktop, hand held or headset microphones

As long as the host audio capable device can be connected using a 3.5mm connector then every opportunity is afforded to the user. Not only speech, but also music and sound tracks and sound effects can be made more audible with enhanced distribution about a space. Audio tracks, narrated texts and books and sounds from Apps and software are used to maximum benefit so that every student can hear properly, wherever they are working in a room.

There are two channels on the Lightspeed panel, both having separate knobs for adjusting the minimum and maximum settings. These are located at the top right hand panel directly above the On/Off status and channel lights (i.e. Ch A and Ch B).

Note: If the iRMC unit is being used, then the optional second Redmike must not be active. It is a case of having the two Redmics in operation, or the primary Redmike and iRMC unit and sound sources. It does not typical infrared ‘line of sight’ as with remote controls, but works well if no obstructions are present in the teaching and learning space. Specifications can be acquired from the Hear and Learnwebsite.

Using Soundfield in the Classroom

The educator or primary user will wear the Redmike upon his or her upper body, using the supplied lanyard. When directing, teaching, instructing and using speech, the students will be able to listen and participate more effectively. If a second person is speaking or responding using another microphone, then the Lightspeed unit provides the second channel as well. Every person who speaks into one or the other microphone can speak naturally, without yelling, raising his or her voice or having to compete with any background noise within or outside the learning space.

A second microphone offers numerous advantages in primary or secondary school settings. Students learn to take turns, moving the microphone about the classroom, sharing and learning to speak only when they have the microphone in their possession. Less inaudible, random or inappropriate comments or responses ensure that all participants can adequately everything being delivered. It is more equitable and allows every student to participate.

Students become more aware of their own performance and their audience. More structured teaching and learning involves every student. Students who have hearing loss or auditory processing disorders are more likely to tune in and engage, as active rather than passive participants. Decreased disruptions, inappropriate commentary and a more democratic environment are conducive to positive outcomes and behaviours.

In this instance, the REDCAT sound panel fills classrooms with the intelligible sound of a teacher or student’s voice. REDCAT produces high quality clarity, no matter where the user stands or sits. It helps save the teachers’ voices by allowing them the confidence to speak naturally. Over time, teachers do not stress and this aids in better overall wellbeing and health. Less stress on the vocal chords, with the addition of having students listen more intently provides an environment that accommodates both the teacher and the students’ needs.

Other competing Soundfield technologies exist. There are fixed and more portable models available from a number of suppliers in Australia. The benefit in having a fixed system includes:

·      Students are always accommodated in a designated space

·      Less interference

·      Less likelihood of damage (i.e. being dropped or inadvertently hit)

·      More likely to be used in a consistent manner (as a matter of course or expectation)

·      Daily use becomes cultural and natural

·      Ability to accommodate one or two students timetabled in that space catering to their specific needs

·      Continued use means increased user acceptance, confidence and expert deployment

·      Repetitive use builds skills and understanding

The benefits in having portable systems includes:

·      Units can move with student(s) from day to day or term by term

·      Units can be timetabled to e set up in different rooms or on non specific occasions (e.g. guest speaker)

·      The system can be moved each year level as a students progresses through the school 

·      Trialing in different spaces is possible to test efficacy or to gauge educator/student acceptance

·      Greater flexibility

·      Increased opportunity for more staff and students to experience the enhanced qualities

·      Units, intended for one student may be used as a mainstream tool to accommodate many if and when that student leaves or moves to another classroom or space where a permanent model is installed

Other Benefits

Soundfield technology, whist directly supporting students who are deaf or who have hearing loss or difficulties, benefits anyone working in a space. Users who have dedicated assistive technology and aids are catered to directly, not only being able to hear the teacher or instructor, but also participate more fully by being an active participant. The student with a hearing loss can hear everyone, and everything being played through other devices.

Podcasting lessons and activities are also made possible. Some Soundfield units have additional software that allows for quick and easy Podcasting. A Podcast is usually referred to as a type of digital media consisting of an episodic series of audio radio, video, PDF, or ePub files subscribed to and downloaded through web syndication or streamed online to a computer or mobile device. The content may be TV or radio or web based. The word is derived from two words - "broadcast" and "pod" from the success and popular use of the Apple iPod, as audio Podcasts are often listened to on portable media players.

In this context, educators can use or create audio suitable content and then save it on a school server, local computer or Notebook, iPad USB thumb drive or external hard drive. Students who miss a lesson, are away ill or cannot attend the class can listen after the event. It is also useful for study and exam purposes or for students who need to listen to content more than once.

Archiving of audio content provides additional support material, or saving exemplars of best practice. Content acquired from special events, Professional Learning sessions or days, guest speakers or significant audio content can be saved and archived. The enhanced quality assures that the audio is practical and useful. If editing is required, software such as Audacitycould be used to tailor the content to a specific purpose or audience. Audacityis free, open source, cross-platform software for recording and editing sounds. 

There is no need to retrofit buildings or to interfere with existing classroom infrastructure. Even sensitive or protected heritage buildings can be easily accommodated with portable systems. If schools were starting a new building program, it would be wise to investigate all of the prevailing systems so that the most suitable Soundfield technology is installed for maximum advantage.  

In Summary  

Soundfield technologies are maturing and there is choice. As with all technology, schools must carefully consider their needs of both staff and students. As Soundfield benefits everyone, it could be classified as the ideal universal access technology as it improves speech music and sound quality in a classroom, auditorium or lecture theatre. Students enjoy being able to hear their teacher or peers without having to have the speaker shout, yell or strain their voice.  

As technology becomes smaller, more powerful and feature driven, at less cost, the opportunity for schools to introduce Soundfield systems is proving to be more than feasible. The benefits far outweigh and cost disadvantage. As teaching and learning is both predominantly visual and auditory, the prospect of improving sound quality is a significant consideration. 

Australian Soundfield System Suppliers

Group Technologies(Linkx Systems Australia Wide); Hear and Learn (Lightspeed Redcat systems Australia Wide) National Audio Systems (Listhttps://www.gtaust.com/news_item/category/contractor/id/316 en Systems, Australia wide); RGB Integration (Extron systems Australia Wide); Word of Mouth (Front Row systems Vic); Printacall (Front Row syshttps://www.extron.com.au in NSW); Cora Barclay Centre (Front RowsystemsSA); Phonic Ear (Front Row systems Queensland) https://www.phonicear.com/.

Useful References and Articles

Assistive Hearing Devices– informative information about students with hearing loss

Soundfield – Assists more than just the Child– A paper presented at ARATA in Australia

Soundfield Systems - Author: Soundfield systems, of which there are many competing companies and models, clearly amplify the teacher’s (or speaker’s) voice. It aids in assisting students to hear and understand directions more easily.Soundfield systems, of which there are many competing companies and models, clearly amplify the teacher’s (or speaker’s) voice. It aids in assisting students to hear and understand directions more easily.Cora Barclay Centre

Note: The CEO (Catholic Education Office) in Melbourne as part of an MSSD program in Catholic Schools in 2013 loaned me a Lightspeed Redcat Soundfield portable model as reviewed in this article. It was proven over a period of time to assist students with disadvantage, hearing loss and auditory processing disorders and disability. The article is an attempt to highlight the many benefits in installing and deploying Soundfield technologies in educational and training settings. 

It is commensurate upon schools and colleges to perform due diligence in identifying and researching brands and models that best suit their needs for individual students as well as for mainstream use. Prices vary and some brands and even models accommodate deaf students more efficiently than others. Models can be fixed to a wall and ‘hard wired’ for safety (in special school settings) or used with Interactive Whiteboards. Other models can be fixed or portable – easily moved with the student from year level to the next year level or classroom or homeroom. Price does NOT determine quality.