AirPods as a Hearing Aid Substitute? Exploring NAL’s Research with Nicky Chong-White, PhD

Hello,

and welcome to another episode

of this Week in Hearing.

I’m Brian Taylor.

Our topic this week is the

AirPod as a hearing

aid substitute,

and with us to discuss her

group’s research on this topic

is Nicky Chong-White. Dr.

Chong-White is a principal

engineer and leads smart

technology innovations at the

National Acoustic Laboratories

in Australia.

Welcome to this Week in Hearing.

Nicky,

it’s great to have you with us.

Yeah, thanks.

And thank you for inviting me.

It’s great to have

this chat today.

This is a really hot topic,

and I think we have a lot of

listeners who are anxious to

hear what you and the now

group have been up to.

But before we dive

into that topic,

I thought it’d be a good idea if

you could share a little bit

about your background and what

you’ve been doing at now for

the last several years.

Yes,

so my background is in speech

signal processing.

I’ve been in this field

for a while,

started off with more speech

coding and mobile

telecommunications,

worked in the US. For a bit at,

AT&T labs.

But I’ve been at NAL for

almost 20 years now,

so it’s a long while

looking yeah,

first starting off with

speech enhancement,

then moving into

Electrophysiology,

and more recently developing a

lot of apps and sort of mobile

technologies to help in the

connected health space.

And certainly now with the

AirPods Pro and them bringing

out the new features,

I was certainly interested

to look at that as well.

Well,

it’s not often that we have an

engineer on the broadcast and

one that’s so accomplished and

is working on such innovative

technology.

So we’re really happy that you

could spend some time with us.

I’m going to start with a

really simple question,

because I get this in the field,

and I know that there’s

confusion amongst consumers

who watch our broadcast,

and that is what AirPod models

have the capability of providing

amplification.

Okay.

So for personalized

amplification of the sounds

around you so that they work

more like hearables,

you need the AirPods Pro.

So they’re the ones have

I got through here?

Oh, you can’t see that.

But they’re the ones,

the short stubby stems and the

silicon tips that feel in your

ear canal. And with those ones,

they have the headphone

accommodations feature and a

transparency feature to hear

the sounds around you.

But if you also just want to

provide amplification

to streamed audio,

then the regular AirPods 2 or

3 do have that feature as

well. Okay, that’s good to know.

You mentioned hearing

enhancement,

turning the AirPod Pro into

basically a hearable.

Can you tell us a little bit

about those hearing enhancement

features that are available

on the AirPod Pro?

Yes.

So there basically three main

features that I see.

So the headphone accommodation.

Feature.

This is one where you can maybe

upload your audiogram or choose

one of the preset profiles and

that applies a frequency

dependent gain to the audio

signal and that’ll make those

soft sounds more audible.

It also does have compression

as well.

The other ones are conversation

boost and that uses directional

microphone and some signal

processing techniques where it

allows the user to focus on the

person speaking in front of them

while suppressing sounds from

the side and behind.

And then the last one is an

ambient noise reduction feature

which uses digital signal

processing techniques to reduce

background noise.

That’s good to know. Now.

I know that the NAL group does.

On YouTube.

I’ve seen it something called

Soundbites. Is that right?

That’s right.

And I know that maybe a year

or so ago you did a video,

one of your Sound Bites video,

providing some details on how to

set up the AirPods Pro to be

an amplification device.

So there’ll be a link on the

bottom of the screen for anybody

that wants to know more details

on how to go through the process

of setting up the AirPod Pro to

be an amplification device.

My next question is

about AirPods Pro.

I think at least here in

the United States,

over the counter hearing aids

is a hot topic. Now,

we know that the AirPods Pro

is not an OTC hearing aid,

but how does the AirPod

Pro compare to them?

What features or what?

I guess my question would be

relative to OTC devices.

We’ll start with the question

what types of hearing losses

might benefit from setting up

an AirPods Pro to be an

amplification device?

Yeah,

so definitely not regulated

medical devices.

They are consumer audio

devices I see,

with some nice to have hearing

assistive features.

So I think that the main target

audience I see them as helping

is people who have occasional

hearing difficulties in

specific situations.

So perhaps they have

a mild loss,

perhaps they don’t even have

a measurable loss,

but do struggle in, for example,

having a conversation in

a noisy restaurant.

So they will work well for that

that you can put in like just a

mild gain use. Some of the,

for example,

conversation boost features,

you might have them in for half

an hour and then they’re in your

pocket or your bag for the

rest of the day. So yeah,

those occasional use

may be a mild gain,

mild loss sort of person.

It seems like a true

multitasking device. I mean,

I use my AirPods to

stream music.

It seems like every day

talk on the phone.

It seemed to be an easy

workaround to turn it into

an amplification to.

Nice to use it situationally.

Yeah, definitely.

I think most AirPods users

bought them for just that sort

of purpose, listening to music,

listening to podcasts or taking

phone calls and being able to

have that multifunctionality and

it’s unless you’ve always

got it on you,

you don’t actually have

to think about it.

I think that’s the real appeal

there of having these assistive

features which you probably

don’t use all that often,

but when you do need them,

they’re right there with you.

Right.

And

since you’re at now

the home of the,

I think the very well known,

very well respected NAL gain

prescription targets,

can you tell us a little bit

about how the gain of the

AirPods pro might compare to

prescription hearing aids when

trying to match NAL targets?

Yeah,

so I think as soon as the

Headphone Accommodations was

announced, my first thought was,

well,

what prescription are

you they using?

So pretty soon we got them in

the lab and started taking

some measurements.

We wanted to see how do they

compare to our NAL NL2.

And yes,

some interesting results.

So what we did is we programmed

up a few different hearing

loss profiles.

So there was a mild sloping

loss, a mild moderate loss,

a flat loss,

and we got them in the lab,

did some acoustic measures with

our hands on our KEMAR

Mannequin and compared the gains

of the headphone accommodations

to the real ear insertion gain

that is prescribed

by our algorithm.

And what we found is that

at normal speech levels,

so around 65 DB,

they match pretty closely up

to maybe about 5K.

They don’t have a lot

of high frequency,

higher frequency than that gain,

but at the loud and the

soft speech levels,

the match wasn’t as good.

So they don’t have as much

compression as we

have an NL2.

At soft speech levels it didn’t

amplify enough compared

to NL2,

and at loud speech levels

there was too much gain.

So it sounds like they’re a

little bit more linear than what

you might find in a prescription

hearing aid,

but they do a reasonably good

job of matching a mild

high frequency,

moderate loss for average level

inputs. Do I have that right?

Yeah, that’s right.

And we have NAL NL2 was designed

to enhance speech

intelligibility while keeping

the overall level at a

comfortable volume.

So not having overly

loud sounds,

now Apple may be prioritizing

a different aspect,

maybe they’re going more for

making music sound better and

not wanting to lose any quality

or not want to have it sound too

unappealing to an initial

person who’s just.

Turned it on for the first time.

So, yeah,

they’ll have different

priorities on how they’ve chosen

that game and I can’t really

speculate on too much on that.

Fair enough.

And I think anybody that has a

probe mic system could evaluate

that themselves and see how they

compare to prescription hearing

aids at matching these different

targets. Yeah.

So I think it’s fair to say that

AirPods Pro does a reasonably

good job matching gain for

average for audibility.

That’s good.

How does the performance and

background noise of the AirPods

Pro compare to prescription

hearing aids?

So, yeah,

we did another lot of

measurements looking at the

conversation boost feeding the

ambient noise reduction feature.

So we had target speech coming

from the front of the person

wearing the AirPods and then

within a horizontal array

of loudspeakers.

So noise coming from the sides

and behind in one scenario and

then one from equally spaced

all around the listener.

And we found between when

conversation boost and ambient

noise reduction were at their

full turned on and

at maximum level,

about a 5 to 7dB

improvement in the SNR advantage

just from measured at the ear,

this was about between 3

and 5dB due to the

directionality feature,

the conversation boost.

And this is basically in line

with sort of conventional

directional microphones

and hearing aids. Now,

some hearing aids have

more sophisticated

microphones and processing that

can do better than that.

But yeah,

for a baseline sort

of hearing aid,

I think we could sort of say

they’re kind of comparable.

Exactly. No,

I think that’s kind of

interesting, for sure.

You already mentioned a little

bit about people that had normal

audiograms or don’t

have any real

hearing loss on the audiogram.

And I know that you did a study,

at least some of the group

at now did a study,

conducted a study using the

AirPods Pro on people that

had normal audiograms.

Can you tell us a little bit

about maybe share some of the

highlights of that study?

Yeah, definitely.

So that study was led by

one of our colleagues,

Joaquin Valderrama.

We have quite an interest

in this particular

group population,

the normal audiograms,

but more than average difficulty

hearing in noise.

So we thought AirPods Pro could

be a good option for them.

The study used let me take a

look at some of the results.

Yeah,

17 participant

self reported hearing and

noise difficulties.

There was a range of measures,

so we had behavioral

speech and test,

speech and noise testing

and then laboratory.

We also did a four week trial

with real world measures

where we.

Send them home was the AirPods

that we provided to them and got

them to rate their experiences

when they were using them in

challenging listening situation.

So what some of the key findings

were that for the speech and

noise testing in the lab,

there was sort of a general

increase across the participants

of 12%.

So from 55% correct on a speech

noise test to 67% correct,

they rated the overall

hearing experience

as a bit better than without

the AirPods.

So there was a slight

improvement.

It wasn’t an overwhelming

improvement.

Some of the feedback was the

amount of hearing benefit

wasn’t really that much,

wasn’t that noticeable

in terms of comfort for

some participants.

The AirPods pro just didn’t fit

well in their ears or were

uncomfortable after

a short time.

And the other one,

which was quite interesting,

which you kind of think

is sort of obvious,

but people don’t recognize

them as hearing devices.

So if you’re having a

conversation with someone and

you’re using them to

hear them better,

they have the perception that

perhaps you’re not listening,

perhaps you’re listening to

music while you’re having

a conversation.

It’s sort of seen as a bit rude.

So, yeah,

they felt they had to it was

fine if they were with family

and they knew the

purpose of them,

but if they were talking to

someone that didn’t know,

they felt they had to always

explain why they’ve got them in.

Exactly.

I have first experience with

that problem that you

just mentioned.

Yes.

But I think what’s really great

for clinicians to know about

this study is that now they have

people that have normal

audiograms but self reported

problems in background noise.

There’s another option

out there.

A lot of clinicians know that

they’ve tried hearing aids on

folks like that and they don’t

do very well typically.

So now there’s another

alternative and I think that’s

good for everybody that’s

concerned about people not

hearing well in those kind

of places. Yeah.

And I will add in

that there were,

I think it was about 30% of the

participants did say that they

would continue using them as

hearing devices in the future.

So even though it wasn’t

everyone or a majority,

there was a sizeable proportion

that did find the value

in them and yeah,

I think definitely yeah.

If audiologists are recommending

them as devices to help people

who probably aren’t ready for

hearing aids or don’t have

enough loss to want

to take that step,

then it is a good sort

of entry level,

sort of stepping stone to get to

doing better for your hearing.

Exactly.

Now,

I wanted to kind of shift

gears a little bit.

Just in the last month or so.

I think it was in Hearing

Review, I saw this,

the publication.

You had a really nice little

study in there that evaluated

the noise cancellation

characteristics of the second

generation AirPods Pro.

That’s kind of an interesting

twist on this device.

So can you tell us a little bit

about what these features are

and how they might

help a person?

Yes,

the AirPods Pro have an active

noise cancellation feature.

Many people actually,

without hearing loss do really

like this feature and

use it a lot.

And it may be a purchasing

decision brought AirPods Pro,

but for example,

in situations like if you’re

traveling on a train or

a bus or an airplane,

definitely where there’s a loud

sort of ambient noise around you

that is quite constant

and consistent.

Active noise cancellation is a

really great feature to really

reduce and sometimes even

totally get rid of that sound.

So it allows you to hear the

audio clearer that you might be

listening to a phone call or

your music or something on your

stream from your phone.

It also reduces that need to

turn the volume right up

so you can hear well.

And that’s sort of the angle we

were looking at it from here

when we see there’s a lot of

discussion about the use of

AirPods and young people,

young people listening to loud

music and potentially increasing

their risk of developing noise

induced hearing loss.

So something like that active

noise cancellation feature can

potentially reduce that risk.

Yeah,

I think that’s really

good to know.

I know there’s so many young

adults out there that listen at

levels that are probably too

loud, and it’s really important,

obviously,

that they should protect

their hearing.

I have one final question

for you,

kind of maybe a crystal ball

kind of a question, and that is,

I think you’ve assembled enough

data to show that pretty clearly

that the AirPods Pro is a

reasonable substitute for a

hearing aid for a lot of

different folks out there.

Obviously not for everybody,

but I wanted you to maybe think

about how the AirPods Pro could

be used in the clinic.

What’s the role of the

audiologist in recommending

fitting, fine tuning them?

What are your thoughts on that?

Yeah,

I think there’s a lot of

opportunities for audiologists

to to fit into this

sort of journey.

I guess if they were to

recommend AirPods Pro to their

clients. So, for example,

to best fit the AirPods Pro,

you would want an audiogram.

There are options where the

person can use an app

on their phone,

but depending on their tech

savviness or ability to do that.

That test,

we don’t know how accurate

the results would be.

So things like taking a quality

audiogram in the clinic,

also

setting up the AirPods Pro

with that audiogram.

If you can see from the

soundbites video,

it’s not the most intuitive

process,

there’s quite a few steps

involved. Um,

you have to be quite invested,

I think, to get through that.

And then there’s the

adjustments.

There’s different slider

adjustments that you

can do to modify.

So maybe you successfully

input your audiogram,

you listen to it and it doesn’t

quite sound right,

maybe it’s a bit tinny,

maybe you want to boost things

up or the overall sound

might be too loud.

Initially there’s adjustments.

So just,

I think walking clients through

those features,

what they mean,

what they do when you would want

to use it. For example,

conversation Boost,

the directionality feature is

one that you manually

switch on and off.

So I’m thinking maybe the

average person doesn’t know when

is the best time to use that,

or when if you’re using it

in a quiet environment,

maybe it’s going to affect

the sound quality.

You don’t really want that on.

So those things also yeah,

I should said before the real

ear measures to check

that amplification

and see is it really

doing what it should be doing

and is it sort of a recommended

sort of amplification for that

person to have. Right.

I see the audiologist kind of

the gatekeeper when it comes to

what’s happening in the ear with

their real earmit measures.

There’s no reason you can’t

do that in an AirPods Pro.

Yeah, definitely.

And just as a trusted

source of advice

for someone to go to

who’s concerned,

I have a great respect

for audiologists.

I have two family members and my

husband and my daughter who

were born with hearing loss.

So I’ve been going to hearing

clinics and hearing all the

hearing advice through that way.

So, yeah,

I definitely think they can

play a role as well

with a different population that

maybe doesn’t have a strong need

or that consistent everyday

hearing support. Exactly.

That’s great.

So,

any final comments? One

I want to remind all of our

viewers that the research,

the articles that we mentioned

today during the interview

will be in a link,

either in the notes from the

broadcast or on the screen.

You can click on it and find all

of the articles that we’ve

talked about today.

And with that,

Nicky, any final comments,

any suggestions for audiologists

out there about working

with the AirPods Pro?

Anything that you want to add

that we haven’t talked

about yet?

And I think generally my goal

in looking at AirPods and

publishing the articles about it

is really just to inform people

of the different options

available.

I don’t see them as a

replacement for hearing aid.

I think they suit a different

type of population and for those

situational use cases.

But I know there will be a lot

of people out there who are

struggling to hearing noise and

are not doing anything about it.

And perhaps they already have

AirPods or some you know,

that’s not just AirPods

we are looking at.

We also do trials on other

hearables, for example,

the Nuheara,

or

we’re looking more into the

OTC hearing aid space.

There are new options coming

available that many people won’t

know about. So yeah,

the goal here is just to inform,

try and let people know,

bring that awareness up.

And I think having Apple put

these beaches in the AirPods

really does raise the awareness

of hearing health.

People are thinking, no,

what’s this?

Maybe I’ll give it a go.

So I see that as a good thing.

And as they say,

a rising tide lifts all boats.

And I think this is a good

example of that,

especially when most of the data

that I’ve seen recently says

somewhere between 80 and 85% of

people that have hearing trouble

are not getting the help

that they need.

So I think all of us benefit

when there’s new players on the

market that people can

have access to.

So thanks for all your great

work in this area. Dr.

Nicky Chong-White,

who’s a principal engineer

at the NAL in Australia.

Thanks for being on

the broadcast.

We really appreciate it. Yeah,

thanks for having me.

It’s been a great conversation.