Balancing FM Systems. BATOD March 2013 Colin Peake Educational Audiologist South of England Cochlear Implant Centre Introduction Welcome to the University of Southampton’s corporate PowerPoint template. This template has been designed to present a consistent corporate image throughout all University of Southampton communications. The design reflects the design standards being developed for Print and Online communications. The template has been developed in consultation with Academic Schools and Professional Services. Please observe the following guidelines if you want your presentation to conform to this style: The University logo must remain in solid blue and not be moved, replaced, covered or altered in any way. Departmental logos can be added to the presentation by inserting them onto the Slide/Title Master in the designated zone at the bottom right. If no logo is available/desired then either delete the place holder or add a descriptive name such as “The International Office” or “School of Humanities” if desired. The fonts, colours and arrow bullet points are part of the style and should be retained if consistency with this house style is required. Need support? Should you require assistance in creating presentations, organising imagery or you would like to make recommendations for ongoing developments the please contact Matt Goode, Marketing Communications, Corporate and Marketing Services on extension 28542 or Sarah Prendergast, Marketing Communications, Corporate and Marketing Services on extension 24174

Balancing FM systems. BATOD March '13 Two Questions …… Why Use Personal FM Systems? What is the purpose of balancing FM Systems? Balancing FM systems. BATOD March '13

Why Use Personal FM Systems FM AUDITORY TRAINING SYSTEMS. Characteristics, Selection, and Use. Ross, 1991 We know that classrooms are noisy places. We also know that deaf children have difficulty comprehending speech in background noise. Balancing FM systems. BATOD March '13

Why Use Personal FM Systems? The ability to discriminate individual phonemes, to hear words/sound differences, is defined as intelligibility, as distinguished from audibility, which is the ability to detect the presence of speech. If because of hearing loss, poor classroom acoustics, and/or poor attending skills, a child cannot discriminate wave from raise, for example, he or she will not learn appropriate semantic distinctions unless deliberate intervention occurs. Carol Flexer in, FM AUDITORY TRAINING SYSTEMS. Characteristics, Selection, and Use. Ross, 1991, Balancing FM systems. BATOD March '13

Why Use Personal FM Systems? “The purpose of using technology is to promote the child’s right to hear and to benefit from educational instruction.” Carol Flexer in, FM AUDITORY TRAINING SYSTEMS. Characteristics, Selection, and Use. Ross, 1991, Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Kimberly Balancing FM systems. BATOD March '13

What is the purpose of balancing FM Systems? To ensure that the level and quality of sound a child hears through the FM Systems microphone matches what he hears through the hearing instrument’s microphone. Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Importance of Level Too High Serious risk of distortion Danger of Compression Too Low Makes little difference to the child Denied the right to access and benefit from instruction Waste of resource Disenchantment Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Importance of Quality Frequency response curves Frequency response curves for Medel Opus 2 (curve #1 @ 60 dB and with CA Digisystem (curve#2 @ 65 dB Balancing FM systems. BATOD March '13

When Should Balancing be Done At initial fitting Change of hearing instrument Change of FM system Disturbance of controls Balancing FM systems. BATOD March '13

Good Practice Fitting Procedure Listening check of speech processor and FM system where possible, adjust settings. An objective test-box method for setting up levels (see Quality Standards and Good Practice Guidelines) Validate the settings with a speech test (eg McCormick) or Validate the settings with a speech in noise test As I mentioned previously we recommend the initial fitting takes place at the implant centre We check the radio aid, set any internal switches, listen to it, then set it an appropriate volume for the user The processor will be listened to if possible, and the appropriate map selected for the 3G with the monitor earphones not enabled. The sequence for connecting the systems is to start with both the processor and FM systems switched off. The FM cable is connected, then the radio aid transmitter switched on, then the FM receiver and finally the speech processor. Then we validate the Fm receiver setting by using the McCormick ATT, firstly without the radio aid, then with the radio aid. We would expect to show approximately a 10-15 dB better result We give an FM booklet which details the settings and instructions for the school, and two small summary cards detailing the user’s map programmes Balancing FM systems. BATOD March '13

But, what if a child can’t do a speech test? May have poor discrimination years after implantation May not co-operate due to tiredness immaturity language difficulties behavioural difficulties Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Callum Balancing FM systems. BATOD March '13

Other Inputs Applied to FM Transmitters Output from Television. CD player, other audio devices Computer/Whiteboard Soundfield device. Balancing FM systems. BATOD March '13

Other Inputs Applied to FM Transmitters Television, CD player, other audio devices, computer/ whiteboard. All should be used with caution – only on children who can report accurately. Soundfield systems . Used in the context of learning so must be balanced. Balancing FM systems. BATOD March '13

Balancing Soundfield Systems Obtain FR curve for hearing instrument Obtain FR curve for FM system and adjust volume so curves match Set FM transmitter to re-broadcast, place soundfield emitter in the test box – lid open. Obtain frequency response curve and adjust output of soundfield system so curves match. Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Demonstration Re-broadcasting.avi Balancing FM systems. BATOD March '13

Balancing FM systems. BATOD March '13 Any further enquiries to: c.peake@soton.ac.uk Balancing FM systems. BATOD March '13