[APPLAUSE]
HELGA VELROYEN: Hi.
Can you hear me?
Ah, nice.
That's what it's all about.
Welcome to my talk.
I will talk about hearing aids and what the
state-of-the-art is.
There will be a little hacking, but not my own.
I know that there are some people interested in my talk
that can not hear very well or not at all.
So I will publish slides that have very detailed speaker
notes so that you can read it afterwards,
if you missed anything.
I hope there will be a recording available.
And if it's possible to add subtitles, I will do those.
OK.
First, a few words about me.
I'm a software engineer.
I am based in Munich.
Some people might know me from my time in Cologne, as well.
I'm more a software geek than a hardware hacker.
So all this is also new to me.
From university, I have a background in data mining and
signal processing.
I worked in the medical industry for a while.
But that had nothing to do with hearing aids.
Also, my current job has nothing to do
with hearing aids.
So this is really just my personal project.
I'm hearing impaired for about 3 and 1/2 years.
So this is when I started to dig into the topic.
And well, yeah, that's just what I will talk about.
Since I haven't seen many talks about audiology here at
the Hacking Congress, I will start with a short
introduction and the process of how you get
hearing aids, actually.
Then what are the current hearing aid models, and what
can they actually do.
Some words about the peripheral hardware.
There's quite a lot of it outside.
And there is some hacking.
And another point is self-tuning, that are people
that tune their own hearing aids, although they are not
audiologists.
So this is an audiogram.
This is a result of a hearing test that you usually do at
ENT doctors.
The x-axis shows the frequency in kilohertz, and the y-axis,
the loudness, level of volume.
The silence is at the top, the really loud
sounds at the bottom.
And the green line you see here is that result of a
normal-hearing person.
And this is obtained by the audiologist. Or the doctor
plays sounds in the different frequencies.
It starts at a very low volume.
And as soon as you hear it, you hit a buzzer or say, yes.
And then they create this curve.
So the blue curve is a typical curve of a
hearing impaired person.
So what you can see here-- that, at the low frequencies,
their hearing is quite well.
That's very typical.
Their hearing starts to get worse in the high frequencies.
And bear in mind that the decibel scale is actually
logarithmic.
So if you have a hearing loss of 60 decibels, it's 1 million
worse than 10 decibels.
So it's not linear.
Another thing that gets measured at an audiogram is
actually the maximum that you can hear or that
you can stand hearing.
So the audiologist raises the volume more and more, and you
have to say yes until it hurts.
So what you see here is the red curve.
It's the level of discomfort.
And also the typical thing is that it raises exactly at the
areas where the hearing goes bad.
This is a very complicated thing for tuning aids because
they can not just amplify everything.
Because you would hurt people very soon, as soon as you get
below the red line.
Another thing is the area where speech takes place.
This is called speech banana.
Actually, that's the technical term for it.
It will rise, of course, according to the language and
the speaker.
For example, female speakers have a little slightly
different curve than male speakers.
And this is the area where hearing aids target, which is
they are used to make you understand speech again.
So they focus on this area, actually.
And you can see the blue line here.
So half of the banana is actually cut.
And this is the high frequencies, which, in speech,
are the consonants like S and F, for example.
The vowels are usually understood quite well.
To give you an impression how I hear, I made a sample.
So this is a song called, "Sad Robot" from Pornophonique.
It's a nice band which makes music with a
Game Boy and a guitar.
And the original--
[SAD ROBOT, BY PORNOPHONIQUE]
HELGA VELROYEN: --has really nice high
frequencies at the beginning.
This is why I use it for testing.
And later, there's also some singing.
So this is the original.
And now I'm going to play my version, so with less high
frequencies and a tinnitus as well.
There's actually a web site where you can download
tinnitus sounds.
[LAUGHTER]
HELGA VELROYEN: And it says that you should actually turn
down the volume when you start broadcasting that because it
can hurt the audio equipment.
So I hope I don't destroy anything.
So I will turn it down first, then slightly increase it.
[SAD ROBOT, BY PORNOPHONIQUE]
HELGA VELROYEN: So this is not a feedback
loop, it's the tinnitus.
And without the high frequencies,
this is how it is.
So it's really hard to actually hear the high
frequencies.
Yeah, so this is just an impression of what hearing
aids have to work with.
Getting hearing aids, I like to compare
it to getting glasses.
So one day you wake up and everything is really blurry.
And you decide well, this is very not so good.
I should go to a doctor.
And then you go to a doctor.
You make some tests.
Then he sends you to an optometrist. He makes some
more tests.
Then you choose a model for your glasses.
And the optometrist orders the glasses and puts
them into the frame.
And then you're happy, seeing nerds.
And then you can see ponies.
[LAUGHTER]
HELGA VELROYEN: Getting hearing aids, unfortunately,
is not that easy.
So one day you realize you can not hear very well any more.
You go to a doctor.
You make some tests.
He sends you to an audiologist. He makes some
more tests.
You choose from the shop of the audiologist
some hearing aids.
And then the audiologist has to adjust the hearing aids
according to your audiogram.
And then it doesn't stop.
So then, actually, the work starts.
You have to go through all the difficult hearing situations
to test if it works with that tuned hearing aid.
So you drive a car.
You listen to music or other people in the car.
You try to have someone whisper something in your ear.
You listen to the TV. Or you go to a party where a lot of
people are talking to each other, and you have to make
out the person that's talking directly to you.
Or you listen to a talk like that where this speaker is
actually quite far away from your hearing aids.
And if you have done all that, you go back to the
audiologist. And you have to tell him why it doesn't work
or in what situations it doesn't really work.
And then he does some changes in the parameters.
And then you have to do that again.
And sometimes you switch to a different
hearing aid, as well.
So this whole process, these iterations, it takes weeks or
months until you have something that is actually
fitting to your ears.
And after that, you're sort of happy.
Actually, I haven't met a person that has hearing aids
that actually compensate for the hearing loss completely.
So whenever you are done with that, you're usually just
stopping because you don't want to spend any
more time on that.
And it works well enough.
Compared to glasses, this is actually a lot more effort and
a lot more frustrating.
Another thing is that hearing aids are really expensive.
A good hearing aid starts at like, 1,500 up to 3,000.
And I only have the numbers for the German health system.
The normal German insurance pays 500.
So there's a lot of money you have to pay for yourself.
Hearing aid models and their features.
There are roughly three types, in-ear units that go
completely into the ear canal.
A more common one is behind-ear hearing aids.
They are for mediocre to severe hearing losses.
The main part is behind the ear.
And another special thing are cochlear implants where parts
of it are implanted into the head and some is attached from
the outside.
I will mostly talk about the behind-ear hearing aids,
because that's what I have and where is a lot of variety on
the market.
Hearing aids got pretty invisible.
These are pictures of me wearing my hearing aid and not
wearing it.
So except for this little wire on the right side, you can not
really see it.
Most people that don't have hearing aids
find this an advantage.
People who have a hearing aid, actually, are not that sure
about it, because sometimes, when you have to ask someone
to repeat a sentence, if they know you're wearing a hearing
aid, they think, OK, she didn't get it
because of the acoustics.
And if they don't see it, they think, she didn't get it
because she was stupid.
So it's really not that obvious.
And sometimes it just helps that people see that you have
a handicap.
They also got pretty small.
This is an example of my hearing aids with a $0.50
piece, so you have an impression of the size.
And you can see that, actually, have just by the
battery compartment.
Out of curiosity, I took my hearing aids apart.
And--
[LAUGHTER]
HELGA VELROYEN: Of course.
[LAUGHS]
[APPLAUSE]
HELGA VELROYEN: You can see they have shells which you can
take off, which is like for mobile phones.
You can switch the color and choose a different one.
And the body--
so I know this picture is not really good.
There's still a lot of plastic around it.
And the white part there is two microphones, the signal
processor and antenna.
That's useful peripheral hardware.
I will come to that.
And the speaker is actually at the part that
goes into the ear.
And what you can also see here, the part that goes into
the ear has also holes where the natural sound can still
come to the ear.
So if you still hear low frequencies, then you can
receive them naturally.
And the hearing aids only add what you can not hear.
This is called open hearing aid.
And it has the advantage that you still hear natural sounds,
which is really nice if you're really sort of an audiophile
person that likes to listen to music.
And so the first thing you do is actually choose that one.
Yes.
I think in the last two centuries,
hearing aids got digital.
And with that, they come with a lot of new features that you
couldn't do with analog hearing aids.
And right now, they are standard in
most first world countries.
And the most important thing is that they can analyze the
situation and react to it instantly, since they have
signal processing in it much more sophisticated than analog
hearing aids did.
Coming back to the audiogram, this is actually a feature
that can also be done by analog hearing aids.
I don't know in what extent, actually.
So if you have a look at this audiogram and only consider
one frequency band, like for four kilohertz, here the
hearing loss is between 60 and 90 decibels.
Over 90 decibels, it gets too loud.
And the input of the environment still has the
whole range.
So the hearing aid has to map 0 to 130 decibels to this
small area between 60 and 90.
It can not just amplify everything,
because that will hurt.
And this is called compression.
This should not be mistaken with compression in audio
files like MP3 or something.
It's a little bit different.
And if you have a look at the software that is used to
adjust hearing aids, it looks like that.
This controls here at the amplification.
And this here reduces the maximum level.
So my hearing aids can, at maximum, do 108 decibels.
And if you have minus 12, you just subtract it from that.
This has the problem that, if you compress it, the volume
gets increased and decreased all the time.
And this can actually make it harder to understand speech,
because the hearing aid is adjusting all the time.
And so to avoid that, they don't compress every time.
So the first area here is linearly amplified.
And only after a certain level, they start compressing.
And this is called knee point.
So they usually try to avoid compressing the speech signal
and only something above that.
And hearing adjusting software, it looks like that.
This is actually an example only from Siemens.
Every branch has their own adjusting
software or tuning software.
So this is just an example.
So here you have the knee point in the first row and the
factor by what it is compressed.
And the third row is a factor regarding how
fast it should react.
So within one syllable, it's adjusted to the right volume.
Ah, OK.
The problem is what do you do when your hearing loss is so
bad that the red and the blue curve actually meet each other
or the blue curve goes all the way down?
And this is actually a problem because then you can not do
compression any more, at least not in the original sense.
So this is a simplified audiogram.
This is the area that is dead.
So instead of compressing in one frequency band, you
compress the frequencies.
So you reserve a part of the still alive hearing
frequencies and map it there.
This is called frequency compression.
And it works only if you have closed hearing aids, meaning
those where you can not hear natural sound any more, where
the ear canal is really blocked by the hearing aid,
because, otherwise, it would be really confusing.
And this is actually offered by only one brand right now,
by a company called Phonak.
And it's actually quite hard to get used to that.
The brain has to adjust to that for a very long time.
What I heard.
I mean, I don't have this.
But still, it's interesting that they try
to do it like that.
A very common problem with hearing aids is feedback
loops, especially if you have open hearing aids.
Then it can happen that the hearing aid captures its own
sound and amplifies it a lot.
There is just this squeaking, what you get when you get too
close to them.
And this is really annoying.
It happens every time something gets
close to your ears.
It can simply be hair, wearing open.
Or you put on a hat.
Or you hold a telephone handle next to your ear.
Or you just want to lie down on the sofa.
Or especially when you hug someone, you start squeaking.
Like you give bionic feedback.
[LAUGHTER]
HELGA VELROYEN: Yeah, this is really, really annoying.
And what the hearing aids do, they try to
detect feedback loops.
So they look for clear sinus signals.
And when they detect one, they send an un-hearable flag.
So oh, I detected one.
And then the affected frequencies get damped until
it doesn't squeak any more.
They can adapt in real time.
So it actually works really fast,
but it's still hear-able.
So the problems with that is that music contains clear
sinus signals.
And those get then damped, which make your music
experience a lot worse.
And also the damp frequencies can be in the speech banana.
And then that means whenever you put on a hat, then you get
a feedback loop.
Then the frequencies get damped.
And then you can not understand anyone any more.
Analog hearing aids did not have a measure against that.
So this is something that is clearly new with the digital
hearing aids.
The screenshot here is also taken
from the tuning software.
When you have tuned your hearing aid, you can make a
feedback loop test, where you place a lot of different
sounds and tries if it detects the feedback loop.
And then it reduces the maximum power of the output of
your hearing aid.
That means you spend hours tuning your hearing aid, and
then everything gets reduced by that.
A very common problem for people with hearing impairment
is the cocktail party problem.
This is when you're in an acoustic setting where a lot
of people are talking and you have some background noise.
And then someone is talking to you.
And you have really problems to figure out the person that
is talking to you.
And there are several factors in that.
And hearing aids react to that in several ways.
So first of all, directional hearing is impaired when you
have a hearing impairment.
The human ear uses two ears and the brain
to locate the sound.
And we use the pinna, that is actually the outer part of the
ear, ohrmuschel, in German.
If you have behind-ear hearing aids, of course, most of the
microphones and everything else is behind the ear.
So you can not use the pinna.
You have to simulate that in a different way.
And this is why both hearing aids have two microphones.
So you have four microphones in total, when you have a
hearing impairment in both ears.
And this way, they can detect if the sound comes
from front or back.
And they talk to each other, so they can also detect if the
source of the signal is right or left to you.
Additionally, they try to recognize the situation and
automatically focus on the person that is talking to you
and also to reduce the background noise in general.
The in-ear hearing aids I showed before, they, of
course, still can use the features of the pinna.
This is also a screenshot from the tuning software.
You can actually test your directional
hearing in real time.
So you can wear your hearing aids
connected to the software.
And then you can do something like that, and see if it's
recognized correctly.
It works, more or less, in a silent room.
But yeah, not in a cocktail party.
Yeah, generally, it's really hard to extract foreground
from background noise, because foreground noise has all the
high frequencies and background noise doesn't.
And if you don't hear high frequencies at all, everything
is one blob of sound.
Hearing aids help with that because they mostly focus on
high frequencies.
And they have filters to filter out
the background signal.
But actually, that doesn't really help so much, because
those situations, recognitions, they tend to
fail as well.
So sometimes it's likely that a person that is talking to
you gets faded out because it is considered as noise.
[LAUGHTER]
HELGA VELROYEN: But sometimes they also work very well.
I mean, it's also coincidence.
Sometimes you're in a setting which has exactly the
situation that the hearing aid can work well with.
So sometimes you are here with a hearing person, actually,
and then you hear him quite well.
And then you start talking in a normal voice, because you
can actually understand everything.
And then that hearing person is asking
you to repeat a sentence.
This is really weird sometimes.
The tuning software for hearing aids also has a real
time monitor where you can see some parameters.
So you wear your hearing aids and then, for
example, listen to music.
And then you can see here the dark areas are where the
hearing aid actually started to work.
Below that, it doesn't need to amplify.
And the grey thing here is the speech banana.
So you see that it's optimized in a way that it starts
amplifying in the speech banana.
It also has the situation recognition
and different settings.
And one of those is music, actually.
I tried it with different types of music.
Actually, if you like heavy metal, you will never see
music here.
It's usually noise.
[LAUGHTER]
HELGA VELROYEN: A problem with hearing aids
is humidity, actually.
So most hearing aids are not waterproof.
That doesn't sound so bad, but actually, a lot of things are
related to that.
So that means no swimming with friends, no pool parties, no
water sports where you'll have to talk to someone.
Sweat is a problem, especially for people
who do a lot of sports.
No audio books in the bathtub.
No heavy rain.
So if you go to an open air concert and it starts raining,
you will really have to take care of that.
Also, just like wet hair, when you go out of the shower, you
have to wait until your hair is dry until you can put your
hearing aids in again.
A very recent development is that Phonak also offers
hearing aids that are waterproof or water-resistant.
They claim that you can hold it under water for 30 minutes,
and then there will be no irreparable damage.
I'm not really sure what that means.
So I guess you probably have to dry it.
[LAUGHTER]
HELGA VELROYEN: Or if you have to give it into repair for
weeks until you get it back.
Oh yeah, by the way, you don't have a spare hearing aid.
So whenever your hearing aids break, you have to go to an
audiologist. And you get spare hearing aids, which is like,
when you drive a Porsche, you get a tractor.
And also, audiologists have opening hours for the elderly.
So if your hearing aids break on Friday night, you have to
wait until Monday until you actually can hear again.
Yeah, those were the important features of hearing aids.
But there is some peripheral hardware that I
would like to present.
So there are different interfaces for which you can
use to plug into your hearing aids.
So the oldest one is the direct audio input, which is
just here, a cable.
So it looks like that.
And it's usually connected to the hearing aid with some sort
of shoe, which looks like that.
And it has the pros and cons of cables, of course, if you
like being on the leash.
But you also have no interference with other
wireless stuff.
It's usually used to plug something else in, for
example, FM or Bluetooth adaptors.
And yeah, this is pretty old technology,
but it's still around.
Although, for really small ones, the plug is actually too
big, so they leave it out there.
Another very common technology is FM systems. You can buy
those from several vendors.
You have receivers and transmitters.
They have different setups like for a meeting, that you
can put a microphone on the meeting table and hear all the
participants talk, or for lecture halls like that, that
you can connect the microphone to the transmitter
and listen to it.
There are some standards, but most receivers and
transmitters don't work with others from other companies.
But at least, if you plug them in with these direct audio
input, you can choose an FM system from a different vendor
than from your hearing aids.
The sound quality is said to be quite good.
I actually could never try it.
But I heard that, actually, in schools, hearing impaired
students listen to music while actually they should listen to
the teacher.
And teachers call the audiologists and ask, could
you make this stop?
They don't listen to what I am saying.
A really common problem for hearing impairment is calling
on the phone.
The problem is, first of all, most people do lip reading.
So they don't rely only on the audio input.
We use the visuals as well.
And of course, you don't have that on the
radio or the telephone.
And also, for technical reasons, the frequency range
of the phone line is reduced.
In Germany, it's like 300 hertz to 3.4 kilohertz.
That's the blue box in this audiogram.
Also the background noise that you have in the room where you
are talking on the phone, it does have the full range.
So you get, actually, background noise in a better
quality than the signal from your person that you're
talking to.
Then, often, the signal is altered and unnatural.
Sometimes you have bad reception.
And also, you hear it only in one ear if you just use a
usual telephone.
And if you hold it to your ear, you get a feedback loop.
So a lot of things make it really annoying
to talk on the phone.
And there are some technical solutions for that.
The most old one is the telecoil or T-coil.
And the source is connected to an induction loop.
And you take off the electromagnetics.
And this is from the telecoil.
It's there in the picture, a really small antenna.
And there are different setups for the induction loop.
So there are adapters that have the induction loop
actually used to hang it around your neck.
Or there are induction loops installed in
lecture halls like this.
I don't know if there is one here.
It's widely used in Europe, especially in Scandinavia.
They even have laws where every public building has to
have one or these public lecture halls.
You have some pros and cons, of course.
You have interference.
When you move inside the induction loop, the level of
volume changes.
So it's nothing where you should dance or something.
But if you sit still in a theater or
something, it works.
Installing an induction loop in a lecture
hall is quite expensive.
But there are actually DIY kits available.
It's quite common that people build their own ones.
And telephones also have an induction loop,
even very new ones.
So all telephones which are called hearing aid compatible,
they have an induction loop that can be used with a
telecoil, even the new iPhone, for example.
And then there's Bluetooth.
There are, right now, no hearing aids that can do
Bluetooth directly because, mostly, of the batteries.
Usually, hearing aid batteries last one week to 10 days.
But with Bluetooth, I think they would only
last a couple of hours.
Although there are no Bluetooth-enabled hearing aids
on the market right now, I've heard that they
are working on that.
Siemens is located in Erlangen, which is not that
far from Munich.
So I have heard about people who would test prototypes.
Right now, you have to use a Bluetooth adapter to use your
hearing aids, attach that.
And there's different versions of it.
So this is an example of Phonak.
They built a really nice thing.
This piece, you hang it around your neck.
And the ribbon is actually the induction loop that is used
with a telecoil.
And to this gadget you can connect several things.
It has direct audio input, which you can use to plug in
an FM system.
It also has aux-in that you can directly
plug in your MP3 player.
And it has Bluetooth.
It actually also has a warning to combine this with
pacemakers.
And I have a friend who has a pacemaker and this thing.
He just ignored the warning.
But I think this is--
[LAUGHTER]
HELGA VELROYEN: Luckily, he's still alive.
And I think this is a good example for what we are
heading in the future.
We will get more and more cyborgs.
And I doubt that every hearing aid vendor is trying their
adapters with every pacemaker there is.
So we will get a lot of compatibility
problems in the future.
And if this really works, it might be an option to kill
people really, really silently, remotely.
[LAUGHTER]
HELGA VELROYEN: I mean, you have to think of that.
[LAUGHS]
Siemens' solution was, of course, not to use any of the
existing standards.
Just build something new.
[LAUGHTER]
[APPLAUSE]
HELGA VELROYEN: So they built something called Siemens Tek.
And it hooks Bluetooth to the phone, or to whatever you're
connected to, and some wireless NFC protocol to the
hearing aids.
So the hearing aids also have a small antenna in it, which
looks kind of like a telecoil, but it is not.
And it is not compatible to anything the telecoil is
compatible to.
So you can only use it with this.
And it has a signal around 3.3 megahertz.
You can see it on that picture.
I tried that.
And it's compatible with every Bluetooth
speaking device, in theory.
And practically, you have to check it with everything.
So whenever I get a phone at work or whatever, I have to
check if it will actually work.
So of course, it works best with Siemens mobile phones.
But you can imagine how old they are.
And yeah, they also are supposed to work with land
line phones.
But on their websites, they say, I think, it was only to
Siemens land line phones, of course.
And other than that, they don't guarantee that it works.
It comes with an additional transmitter that you can
connect to your source that is more far away.
The Tek itself has a range of one meter.
So if you want to have a flat screen TV, I don't know, five
meters away from you, you could use the transmitter.
This thing costs about 400 euros for just turning one
wireless protocol into the other.
And no insurance is going to pay for that.
So you have to pay for this on your own.
If you have a generous employer, you might
get some for it.
They also released a new version of it.
This is on the right side here.
It's called miniTek.
And it has, actually, less features than the old one
because they removed the display.
And they still want 400 euros for that.
And you don't get a discount if you bought the old one.
Well, but I guess that's marketing.
This is the sender with the transmitter.
So you connect it to the computer, and you wear the Tek
around your head.
It also has some patents for the different programs. So
hearing aids have different programs that you can change
manually so that you have one for listening to music, or one
for your living room, and one for outside, or whatever.
Of course, I took that apart as well.
[LAUGHTER]
HELGA VELROYEN: You have to couple this Tek with the
tuning software of hearing aids.
So there is some kind of authentification via a
7-character serial number.
I doubt that there is actually a lot of encryption in there,
because the latency is crucial.
Bluetooth already has a latency.
And you don't want to add that much to it.
But I also tried to use a different Tek with my hearing
aids, and it actually doesn't work.
So some kind of authentication must be in there.
But if you're too lazy to hack that, you can
still hack the Bluetooth.
There are lots of talks about that here.
And of course, the PIN is 000.
And something that is not directly about the Tek, but
the hearing aids also communicate with each other.
So if I switch the program-- there's actually a small
switch on my hearing aids--
if I switch between the programs on one ear, it also
tells that to the other ear.
And that one doesn't use authentification.
I have heard that, when people have the same model of hearing
aids and they're close to each other-- for example, this
happens when couples buy the same hearing aids--
then you switch your program, and your spouse also gets the
program switched.
[LAUGHTER]
HELGA VELROYEN: And this can actually only be changed by
the audiologist by changing the channel.
So they have, like for wireless, different channels.
And you'd set it to a different one.
That's the security about that.
Yeah, hacking.
When I started to dig into that topic, I was really
disappointed that there is not very much hacking.
So there's one forum called hearingaidhacks.
livejournal.com.
This is the biggest one I found.
But if you go through the entries, it's mostly people
asking for technical advice, So, I bought this and this
hearing aid.
What peripheral hardware can I use with it?
I guess the reason for that is that the
devices are really expensive.
And the warranty and the insurances are really not that
nice if you break your own hearing aids.
And you still have this problem that audiologists
don't have opening hours.
They can not be used by people who still have a life.
So people are a little resistant to actually hack the
hearing aids.
But there is a little hacking on the peripheral hardware.
I will show two examples for that.
There's one guy called Gertlex who built his
own Bluetooth adapter.
And he posted this on Flickr, quite detailed.
And what you can see here, he used a Sony wireless Bluetooth
headset, and hacked it in a way where you can connect the
direct audio input cables from the hearing aids.
The picture here in the upper-right corner shows the
setup when he tested it.
So he actually didn't test it with his
original hearing aids.
He used an old one that he had.
And he even used an old MP3 player because he was afraid
of frying that as well.
So this is the precaution that you have to do when you start
frying your hearing aids.
You can not only fry your hearing aids, you can also fry
your hearing even more.
So you should be careful.
And there's another guy who also made a Bluetooth adapter.
And he also took the DYI cables here, those shoes that
you use to connect them, and a Bluetooth mono thing here.
And this is actually the result, that you connect it
directly to the hearing aids.
He also provided some nice diagrams for that.
The slightly bigger scene is actually the self-tuning
scenes for hearing aids because, as I said, it's kind
of frustrating to get hearing aids.
You have to go to the audiologist a lot of times.
And he asks you, yeah, what's wrong?
And then you have to describe the situation.
But you're sitting in this silent cavern at the
audiologist, so the adjustment is not really done in
realistic circumstances.
And a lot of people get frustrated about that.
So they spend weeks tuning their hearing aids at the
audiologist. And still they're unhappy with it.
So they try to get the hardware and software that is
necessary for it.
And those are actually only sold to doctors and
acousticians or audiologists.
And they are not sold on eBay because
it is medical equipment.
And that is not supposed to be sold on eBay.
So you have to use other channels.
There's a black market for it.
It's kind of hard to put a price on that, but I've seen
offers for the hardware, which is called Hipro.
And there are different versions for
serial use via Bluetooth.
And it starts with a couple of hundred euros.
So you can imagine the pain that people have when they
already spent 5,000 euros for two hearing aids.
And then they spend even more money, because they want to
tune them themselves.
And there is this self-tuning scene.
And people really hack the system.
The effort for people who actually installed a fake
business, so they register a business for an audiologist to
buy this hardware and then stop the business again.
So there are actually people doing a lot of effort to get
this hardware and software.
But of course, then you have no customer support.
And when you fry your ears or your hearing aids, then it's
your own fault.
There's one exception.
In America, there's a hearing aid manufacturer called
America Hears.
They sell quite low-budget hearing aids, up to
$1,000, if I'm right.
Then you send in an audiogram of yours.
And they tune it at their place for the first time.
And then you can download the software and tune it a little
bit more at home.
Unfortunately, I've never seen that software.
You can only order it in the US.
But I would be interested to have a look at that as well,
if someone has channels for that.
Of course, some of this hardware ended up in my hands.
This is a serial Hipro.
This looks really fancy, like a modem from the '80s.
It's connected via serial.
And you connect the hearing aids to it.
I have some close-up pictures for that.
So you take out the battery and put on a small cable which
has a contact of the battery, the size of the battery, a
very flat cable.
And this is connected to a bigger cable.
And that is connected to the Hipro.
The Hipro is the same for nearly all hearing aid brands,
so you can use it for Siemens, and Phonak, and whatever.
But these small, flat cables, they are different for nearly
every hearing aid.
So if you try to buy this Hipro on the black market, you
also have to buy those cables.
There's also a Bluetooth version that also
ended up in my hands.
It looks like that.
And it has the advantage that you are not
connected to it via cable.
So you don't feel like on a leash.
And I haven't really used that much.
But this way, you could actually go outside and tune
it in the subway or at your office, because
you just need a laptop.
And it works without your powerful wire.
The tuning software, I showed you some excerpts from it.
This is just another screenshot.
On the right side here, you see the different programs. So
the universal one, here is one for music, and one for the
tech, if you work with that.
When I was playing with the tuning software, I found
something very interesting.
That it's actually spying on me.
So it locks some stuff and, for example,
how much I wear it.
Although I find 14 hours a day a little bit--
I think I'm awake, actually, longer than 14 hours.
But they use this, actually, because people come and
complain, yeah, this doesn't really work much.
And then they see they only wear it half an hour a day.
And so, of course, you can not get used to it
and adapt to it.
And you can also see what different programs are used.
So mostly I use the universal program.
And sometimes I have another one called universal that is
actually tuned to have less feedback loops.
That's the one I use when I put on a hat so that I still
hear a little bit, but don't have too many feedback loops.
And it also tracks how often I was in a noisy environment or
was listening to music.
And since I like to listen to heavy metal, this is actually
not correct.
Yeah, I found it really interesting
what you can see here.
And yeah, I hope that it doesn't record anything what I
talk about or what I listen to.
We have a little bit more time, so I will talk about the
cochlear implants, as well.
I mentioned that those are the ones that are half implanted
in the head and also have an external device.
This shows this part is implanted.
And we have a wire that is drawn into the cochlea.
And it's connected to the nerve.
So actually, the whole ear is circumvented.
Only the wire goes directly to the nerve and
then through the brain.
And cochlear implants are what I find really fascinating.
They really make deaf people hear.
It's only applied to people who have a really severe
hearing loss, like less than 20% or something.
So they hear only less than 20%.
Of course, it's a surgery to insert that.
It destroys any remaining hearing, because you poke a
wire into the nerve.
So everything else is gone then.
It can also affect other nerves.
So I have a friend who had this surgery.
And they touched some taste nerves as well, so everything
tastes as metallic.
It was kind of weird.
But it actually went away after a while.
The signal is really different.
The brain has to adjust to that very long.
There are actually hearing courses after you get this
surgery and the device is started.
You have to really get used to that, because it's like
electrical signals directly [? intruded. ?]
And the technology of this device, this is usually behind
the usual hearing aid technology, because it has to
be well-tested before you put something into your head.
And like for the other hearing aids, there are not many
standards, no interoperability between the brands.
So if you decide to take the cochlear implant of one brand,
you can never switch to another one.
So yeah, you have to think that through.
I have an example of how it sounds
with a cochlear implant.
So it sounds kind of spooky.
It starts with a normal sample that everyone can hear it.
And then they have different channels and reduce the number
of channels.
And then it gets less and less hear-able.
[AUDIO PLAYBACK]
-A boy fell from the window.
A boy fell from the window.
[UNINTELLIGIBLE].
[END AUDIO PLAYBACK]
HELGA VELROYEN: Yeah, so you can imagine that it takes a
while until you actually can understand speech with that.
Yeah, I'm coming to an end.
So there are a lot of things that I want from the industry.
First of all, better service.
And that goes into the consideration of young
people's needs, because you can feel it every time, that
everything is designed for the elderly.
They don't consider that people actually have to work,
and have a life, and actually want to go out and talk to
people, and not only in a silent room one-on-one.
And there are a lot of things where you miss the support
when you have hearing aids and are not 60 or something.
Generally, I'd like to have better signal processing.
Of course, regarding the size, they already did a really good
job, if you consider what they do already.
But actually, the cocktail party problem is not solved.
So a lot of people who have hearing aids and then who also
have really good hearing aids, they just avoid social
situations.
So they don't go out.
They don't go to the Congress.
They don't go to parties.
So whenever you would ask them to go for dinner, they'd
really carefully choose the restaurant, if it's a more or
less crowded one so you can understand people, actually.
What I'm really missing is some standards.
It would be even cool if it was open standards, because,
this way, you feel really trapped as a patient.
There's this saying, "If you can't open it, you don't own
it." And I really miss that when having hearing aids.
So I have a lot of ideas how to improve that.
But I don't see most of it coming in the next 500 years,
because the companies are not very open source friendly.
So what would be really cool, to have something like a
hearing aid app market that you can download the newest
feature for a background noise remover or something, and that
you can write you own filters and share those, and
especially exchange those between different brands.
And the funny thing is, when I was browsing through the
websites of the vendors, the marketing of some hearing aid
companies actually got this idea already.
They just call their features apps.
So this is just an enumeration of what the
hearing aid can do.
But they just call it app.
[LAUGHTER]
HELGA VELROYEN: And it would be really cool if there was
something like that.
You can exchange those.
What I would also like, hearing aids do not use
reoccurring situations.
Most people have a rather steady lifestyle.
You live in the same apartment.
Most of the time, you work in the same office.
You take the same subway to work every day.
And hearing aids are only tuned for a general situation.
But I think signal processing works well the more you know
about the surrounding.
So it would be really cool if you have one program for the
office and one program for at home and one for the journey
to the office.
And we carry something around that knows all this.
I mean, we have smartphones, and they have a calendar, and
it shows where you are.
And it knows the people that you're talking to and even if
you talk to them on the phone.
So there could be parameters for each person
that you talk to.
And that could be saved on the smartphone, if there wasn't
enough space in the memory in the hearing aids themselves.
So all the information is actually there.
But I don't see any of the hearing aid
vendors adapting to that.
And what I also think, there are people building 3-D models
of houses, and you could take this information into
consideration as well.
So if I have never been to the BCC, but someone has made a
3-D model, you could also get the characteristics of the
acoustics here.
And then, before you go to the Congress, you could download
the acoustic settings for your hearing aids.
That would be really cool.
But, well, this is just ideas.
Yeah, and then also regarding the hardware, it would be nice
if there were some open standards.
It would be cool if you could print your own hearing aids
with a 3-D printer, at least the part that goes into your
ear so that it fits really well.
And there are a lot of possibilities.
But the market is really, really slow.
And they still try to figure out how
do we connect Bluetooth.
And for me, it's just way too slow.
I'd like to see more progress in that.
Yes.
Actually, with that, I would like to conclude.
And I have to thank some people who helped me with this
work, with the talk itself and all the stuff I talked about.
And yeah, I think we have some minutes for questions.
FEMALE SPEAKER: Yeah, and that's--
[APPLAUSE]
FEMALE SPEAKER: Wonderful.
So before we come to the questions, I need to say three
things, which means please stay seated while the question
and answers are going on.
Then please pick up your trash and your water bottles and
take them out with you.
And then please leave through the front door here, while the
last door over there is the entrance for the new people.
So now we can go over to the question and answers.
We have a signal angel again in the IRC sitting and
watching Twitter.
And we have an audio angel in the back running around with a
microphone.
So please, questions now.
AUDIENCE: Hi.
I have a question about the cochlear implant [? hat. ?]
I'm a neuropsychologist. And I know that, with eyes, there's
an approach to re-engineer the signal
processing of the retina.
And with this kind of knowledge, you can make better
retina implant [? hats ?]
to enhance the possibilities of seeing with
this kind of aid.
And is there a similar approach for hearing aids and
the cochlear implant [? hat ?]?
HELGA VELROYEN: There are different
types of cochlear implants.
And this is really not much of my field of expertise.
I know there are those who still use the membrane in the
ear or some directly, the ones that I showed, that directly
insert the wire into the nerve.
But I am not that familiar with the field, so I don't
know what's coming there.
AUDIENCE: OK, there's a question from the front row.
I wonder, is there any connection of research in
companies like Siemens or whoever builds these parts?
Is that, in any way, connected with other
consumer good research?
I'm not hearing disabled.
But if somebody would come up with a decent set of in-ear
headphones that would fit and would be able to have some
noise cancellation also, I'd be quite interested in
spending money on that.
But this seems to be totally uncorrelated altogether.
HELGA VELROYEN: Yeah, that's true.
I mean, it's pretty close to in-ear headphones.
But it's still, from what I've seen, a different market.
You still can buy new hearing aids, if you
don't really use them.
No one can prevent you from that.
But I don't see any trend in merging that very much.
Is there any more questions?
AUDIENCE: Hello.
I would like to add two things to your wish list. One thing,
I would like the hacker community to find out what the
real differences in devices from different price ranges
are, what is done in hardware and what is
actually only firmware.
My audiologist reported devices coming back from
repairs or programming to report as more expensive
devices, for instance, where it's just a firmware thing.
And the other thing is I see an interesting hacking attack
angle for hacking in the protocol that the devices use
to communicate with each other, with the devices which
transfer Bluetooth into the body area network that really
speaks to the devices.
So do you know any off-the-shelf components that
can speak these body area network protocols?
HELGA VELROYEN: For the Siemens thing I showed, I
haven't found anything.
So this is just that gadget that I have. But I think
people are experimenting with the audio induction loops and
the FM systems. But yeah, it's not that much that you can see
documentation of that.
So I'd like to see more here.
I made this talk because I would tell you hackers what's
on the menu.
And it would be really nice if there was more
activity in the scene.
And it's kind of hard to start that if you're all alone.
So I hope I've risen some interest. And if you have any
pointers for me or anything I didn't mention here, I'm also
happy if you send me an email.
Or I will be around the next couple of days.
FEMALE SPEAKER: Before we finish, there are some
questions from the internet.
The first one is Gilligan who asked, does the fact that you
have tinnitus make the process of tuning a hearing aid for
you harder?
Does a hearing aid have a negative or positive effect on
your tinnitus when you wear it?
HELGA VELROYEN: Of my what?
Sorry.
A positive or negative--
FEMALE SPEAKER: Does the hearing aid have a negative or
a positive effect on your tinnitus when you wear it?
HELGA VELROYEN: Actually, yeah.
There are hearing aids that claim to [? counter-fy ?]
the tinnitus, that they generate the
counter-frequencies against that.
I also asked my acousticians or my audiologists about that.
They actually don't work.
I mean, they usually are not really offered.
And even if you ask for it, they tell you, yeah, usually
they don't really make a difference.
My choice was actually just to make a normal hearing aid.
And because the frequencies that you don't hear very well
are amplified, the tinnitus, in relation, gets as loud.
And you learn to ignore it.
That's not really magic, but that's the only thing that
seems to work.
FEMALE SPEAKER: OK, the next one is from [? Schpegmada ?]?
Are there hearing aids with documented RP for the tuning
official doc reverse engineered?
Can you get the official tuning software to tune
yourself that you write through any people who
manufacture them?
HELGA VELROYEN: I haven't found anything about that.
The only thing you can do is get the software on the black
market and disassemble it, if possible.
But there are no API system thing.
That's really what I'm missing as well.
FEMALE SPEAKER: OK, the last one is from Lucy, I guess.
What frequency range can you usually hear
using a cochlear implant?
How fine can you resolve frequencies?
HELGA VELROYEN: They are about the range that you have in the
speech banana.
But actually, I'm not that familiar
with cochlear implants.
So I can not give the details here.
AUDIENCE: OK, hi.
You showed us the programming tool for changing the settings
on the hearing aid.
I've forgotten the name, but the 1980's modem.
Have there been any attempts to clone that hardware or
reverse-engineer the spec?
HELGA VELROYEN: I'm not sure if I understood correctly.
You mean like how you get the hardware for this?
AUDIENCE: Yeah, so the moment you have to buy the
programming tool, as I understand,
to update the software.
HELGA VELROYEN: Since it's only delivered and sold to
audiologists and doctors, you have to be friends with
audiologists or doctors.
And somehow they can give you that.
But there's no official channel.
So you have to find the black market.
AUDIENCE: Yeah, sorry, my question was has anyone tried
to create an open hardware variant?
HELGA VELROYEN: No.
AUDIENCE: Has anyone copied?
HELGA VELROYEN: No, I haven't found
anything like that either.
So that was actually also on my wish list, that makes the
tuning hardware open source as well.
That would be really nice.
But it's a serial device, so you could actually do some
sniffing there.
But I haven't seen any approaches there.
AUDIENCE: Yeah, because it looks pretty
easy, I would say.
[LAUGHTER]
AUDIENCE: Yeah.
FEMALE SPEAKER: So we are running out of time.
Is there any really, really important question left?
I mean, because she's around, so you can meet her in the
next days on the Congress again and
ask her more questions.
And thank you very much for the talk.
It was very interesting.
[APPLAUSE]