User guide

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Soundfield Systems
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Classroom soundfield FAQs
I’m not very technical, is a soundfield system
complicated to operate?
Not at all. In fact, once the controls have been set initially,
they rarely need further adjustment.
I don’t want to feel like I’m talking into a PA
system ‒ will I hear myself?
No, don’t worry. A soundfield system is designed for low
level sound reinforcement. If you can hear your own
voice loudly from the soundfield, then the volume is set
too loud.
Will having a soundfield system in the room
distract the class?
Quite the contrary ‒ it is far more distracting for children
to have to strain to hear the teacher. The equipment
itself is very unobtrusive and the sound distribution is
designed to give a natural spread of sound around the
room, helping the students to focus their attention on
the teacher.
Do I have to pass my microphone around the class
for questions?
All our classroom soundfield systems have the option to
add a second microphone and we strongly advise the
addition of a handheld microphone to encourage
student participation.
I’m looking for a system for my classroom but I
don’t know whether a Roger Dynamic soundfield
would be better than an Infra Red soundfield‒
what’s the difference?
Essentially it makes no difference. Generally Dynamic
SoundField is particularly popular in schools where
Phonak personal radio aid systems and Roger inspiro
transmitters are already being used, while infra-red
systems offer the broadest choice of transmitters,
microphones and single or multiple speaker options.
The Phonak SoundField system uses a radio signal to
send the teacher's voice from the transmitter to the main
speaker unit. It is digitally coded so you can use many
different systems in the same school. As with Phonak
personal radio aids, it is 'Dynamic' meaning that the
soundfield system automatically adjusts itself in response
to the level of background noise in the room.
Infra Red systems use a non-visible light to send audio
signals (in a similar way to a TV remote control!). This
light cannot travel through walls so there are no
limitations on the number of systems on a site.
The choice is yours and please do talk to us if you need
help making your decision.
Does sunlight stop an IR soundfield working?
An infra red soundfield uses modulated infra red signals
to transmit the teacher’s voice. The infra red ‘carrier’ can
carry a number of channels, which means two
transmitters on our systems. The detectors have ‘black’
optical filters which means that sunlight does not
normally cause problems. Having said that, it is
important that IR sensors are kept away from direct
sunlight but as they are normally installed at ceiling
height this would rarely be a problem.
If sunlight does not stop an IR soundfield working,
why can windows sometimes cause a problem?
IR soundfield systems work well in a room with typical
windows ‒ only a whole wall of glass windows might
cause a problem. As windows are glass, most of the infra
red signal passes through and only a few percent is
reflected back into the room. However, in that situation,
there are usually blinds which will reflect the IR
transmitter
signal. Infra red
travels in
straight lines
and a central
sensor picks up
the signal from
the transmitter
by reflected
signals when
the teacher
faces away
from it.
What can we do if there is a large area of glass?
An additional sensor can be fitted on a wall to pick up
the IR signal when the teacher faces that direction.
The drama studio has very dark walls and curtain
partitions, will this cause a problem for an IR
soundfield?
The dark surfaces absorb the IR signal just like they
absorb visible light so we would advise fitting a system
using radio microphones in that room. It is often more
appropriate in a drama studio to fit a SYS10 system with
multiple microphones and other inputs. Please contact
customer services to discuss your requirements.
I have heard that plasma TVs can cause interference
with infra-red sound systems, is this correct?
Yes, plasma TV’s emit a modulated infra-red signal which
causes an audible
interference with
all infra-red
soundfield systems.
Conventional LED
or LCD TVs do not
cause a problem.
Plasma TVs are fine
with our UHF hall
sound systems.