Cohousing-L Mailing List: Soundfield systems/induction loops: easier listening

[Laura Polich (laura.polich]

I see that people are discussing how to improve the acoustics in meetings
and other large and noisy rooms. Wonderful.

I see some people here are advocating for induction loop systems. Looping a
room is often a good idea and can improve ability of people to hear, BUT,
you have to have a telecoil switch on hearing aids or another device to
pick up the signal and get it into the listener's ears. The loop itself
does not put out an acoustic signal. It sends out a magnetic signal which
hearing aid telecoils can pick up and translate to acoustic energy that is
processed by the hearing aid. The problem is that telecoils are not so
common nowadays. You can usually order a telecoil program or a switch when
buying hearing aids (or cochlear implants), but for some companies you have
to choose between the telecoil and some other feature (can't have both
features). Often people choose the other feature because they don't know
how useful telecoils can be. So I hesitate to recommend loop systems
because they might not be available to some hearing aid users and they do
very little for people who could use some acoustic boost but are not yet at
the stage of getting hearing aids.

A better option (in my humble opinion) is a sound-field amplification
system. This is a system that transfers the signal from a microphone to
speaker(s) placed around the room. Just like loop systems, the speaker
talks into a microphone but the sound is amplified for everyone (acoustic
to acoustic, rather than magnetic to acoustic). The goal is simply to make
the signal (what you want to hear) louder than the ambient noise (what you
don't want to hear). It does not take that much volume to do that. A signal
5 dB louder than ambient noise (5 dB signal-to-noise ratio) will sound a
bunch better, and a signal-to-noise ratio of +10 (signal is 10 dB louder
than ambient noise) is usually sufficient for almost everyone to hear
easily (people with severe hearing loss might need a higher signal-to-noise
ratio). The amplified signal is available to everyone -- those with hearing
aids, but also those not using hearing aids. Everyone in the room hears
with less effort. These are recommended for classrooms which are rather
noisy environments. Daybreak Cohousing has been using a sound-field
amplification system for at least five years. At first we had many members
who did not want to spend the money on the system because they felt that
they personally did not need amplification so it would be a waste ("we hear
just fine without an extra piece of equipment.") With persistence, we did
get the system, and after a few weeks of using it, people kept coming up to
me saying how much easier and less stressful it was to sit through meetings
-- and they were the ones with "normal" hearing! The people with hearing
loss were even more ecstatic. Now we use the soundfield system at every
plenary, and we have also used it at many community functions, and even
outside groups using our Common House use it, and it always gets rave
reviews. It is portable, so it can even be taken to off-campus events.

We bought a "Redcat" system from the Lightspeed company in Tualatin, Oregon
(suburb of Portland) (https://lightspeed-tek.com/about/). The Redcat is
easily set up, easily portable and easy to use. It is commonly used in
elementary classrooms (where teachers want a trouble-free, easy-to-use
system) and one of the people who benefits most is the teacher because they
no longer have to shout to be heard by the students (a lot less fatigue at
the end of the day). The loudspeaker plugs into an electrical outlet, but
the microphones have to be charged with a charger. The biggest problem we
have with the system is when someone forgets to charge the microphones
before the meeting.  We chose Lightspeed because it was a company close to
us so it would be easier to get troubleshooting or repair support, and it
was less expensive. There are multiple good companies making soundfield
amplification systems all over the US (and internationally) so there are
many options to choose from.

Laura Polich
Daybreak Cohousing
Portland, Oregon