Getting the best performance from a microphone is essential to the success of a presentation or speech, to clearly communicate the message and to engage the audience. HowToAV talks to Eddy Brixen of DPA Microphones about microphone techniques, correct choice of microphone and loudspeaker equipment and voice clarity for presentations.
When designing an audio presentation or public address system, it is key to ensure that the potential different hearing abilities of the audience are understood and addressed. Not everyone in the audience will have fully unimpaired hearing; in fact, research has shown that around half of audience members will have some form of hearing loss or hearing impairment.
Therefore, this must be considered in the volume levels, speaker placement and additional assistive listening technologies (eg. induction loop systems) employed as part of the overall audio system design.
A little bit of training on microphone technique can go a long way when it comes to clarity of voice and a successful presentation!
Don't expect all presenters and speakers to be confident with their microphone technique - in fact, many very able and eloquent speakers will try to avoid using a microphone at all! (see: "I'll be fine without thanks, I've got a loud voice!.."). Initially some users may find using a microphone off-putting - and they might assume that is they can hear themselves, so can everyone else.
Explain to them that the size of the audience, acoustics of the room, ambient noise levels, etc will make it more difficult for the audience to hear everything that is said. And if the audience can't hear clearly, they will quickly lose focus / interest.
In addition, for any audience members with hearing impairments who make use of assistance listening technologies, it is essential for the presenter to use the microphone in order for hearing technologies to function.
There are a number of architectural and acoustic factors of a room that will affect the performance of a microphone / audio system; size and shape of the room, ambient noise, reflectivity of the environment and number of people in the room, for example.
How can you reduce reverberation levels in the room? Hard, acoustically reflective surfaces in the room will significantly increase reverberation of sound, making it much more difficult to understand what the presenter is saying. By adding acoustically absorbent materials to the room - such as carpets, curtains or acoustic panels - will greatly reduce the reverberation levels therefore improving the sound.
Ambient noise is any unwanted sound and noises within any area / location; this could be noise from adjacent rooms, equipment such as computers or air conditioning, activities or traffic from outside the building, etc - or it could just be a lively / noisy audience!
It is important to consider and factor-in any ambient noise and how it could affect the sound and voice clarity in a presentation. And remember that ambient noise is likely to be unpredictable - equipment, traffic, people are likely to fluctuate on different days and at different times throughout the day.
Increasing the volume level of the presenter's voice is one solution, of course; but, where possible, reducing the ambient noise level will always be a better option!
What microphone you consider for a live presentation/conferencing all depends on:
Microphone placement is important for optimal clarity and for effective audience engagement.
Ensuring that the microphone is in a comfortable position / height for the presenter will help to ensure that they position themselves at the optimal distance from the microphone.
Using a gooseneck microphone allows different presenters to easily reposition the microphone to a comfortable height. Roaming or wireless microphones have full flexibility of movement, of course, but a little training with each presenter is always recommended to help avoid clipping, distortion or feedback.
Positioning the loudspeakers correctly should result in even, clear coverage of the presenter's voice for all members of the audience, whilst at the same time ensuring the sound seems natural - not overly loud and that the sound appears to coming from the presenter, rather than somewhere else in the room.
A well designed permanent audio installation will ensure all these factors have been addressed, but what about a portable or temporary audio system?
In many cases where there is no installed public address system, a portable PA system can be used. Usually featuring a powered (or 'amplified') loudspeaker and wireless microphone(s) - and often battery powered, a portable PA system is ideal for smaller audience presentations, for transporting in the car between venues or for storing away in a venue cupboard when not required.
But this level of portability can have its problems if not used correctly, resulting in bad sound quality, feedback or an unnatural sound source direction. Where possible, use a more powerful portable PA system so that the system isn't being driven to hard or at full volume. This will help with quality of sound and reduce issues of feedback.
It might be tempting to position the powered speaker as far away from the presenter as possible (with the intention of wider coverage) - and a frequent mistake is to place it at the back of the room. This is likely to result in a very confusing and off-putting direction of voice - as the audeince see the presenter in front of them, but hear their voice from behind.
High quality audio equipment quite simply, results in better audio reproduction and better results for the presenter and their audience. High quality microphones will pick up the voice better, high quality speakers will reproduce the sound better.
CIE is one of the UK's leading distributors and system designers for professional audio and public address.
With over 50 years experience in supply and system design for many of the UK's largest, high profile audio projects, our AV experts provide a unique level of technical support and customer service.
Call the CIE audio experts now on T. 0115 9770075 or contact us today.