Oticon Agil
Connectivity
Matters
- A Whitepaper
Agil Improves
ConnectLine
Sound Quality
Whitepaper
M. Lisa Sjolander, AuD
ing the ConnectLine have shown fast acceptance of
Oticon A/S, Smørum, Denmark
ConnectLine and self perceived benefit2. This paper
concentrates on improvements to sound quality for
Agil Improves ConnectLine Sound Quality
streaming with Oticon’s Agil hearing instruments
and ConnectLine.
Wireless technology is part of our lives from the
garage door opener, FM or satellite radio in the car,
The improvements to sound quality are integrated
Bluetooth headsets, cell phones, lap top computers
in the Agil hearing instrument; ConnectLine has
and hearing instruments. The increased availability
the same easy to use functionality as before, just
of wireless technology in external audio devices and
with better sound quality. Two new algorithms,
new wireless technology in hearing instruments al-
Power Bass and Music Widening, were developed
lows hearing instrument users to connect to an ever
to enhance sound quality with Agil hearing instru-
increasing number of audio devices.
ments and ConnectLine; together these features
are called Connect[+]. Agil and ConnectLine continue
For several years a team of engineers and audi-
to provide easy to use connectivity to external au-
ologists at Oticon has focused on improving several
dio devices and to improve speech understanding.
common listening situations using wireless tech-
Improvements to sound quality are motivated by
nology. This led to development of the Connect-
listeners need for excellent sound quality in all lis-
Line; ConnectLine is a family of devices: the Oticon
tening situations. In fact, sound quality and signal
Streamer, TV Adapter and Phone Adapter that allow
processing were rated the most important factors
Oticon hearing instruments to wirelessly connect to
for hearing instrument consumers’ satisfaction in
up to eight external audio devices. ConnectLine is an
Marketrak VIII3. Sound quality for streaming was im-
integrated system, which unique because it allows
proved by focusing on the unique problems that oc-
flexible switching between devices with the push
cur when streaming namely a lack of low frequencies
of a button. For example, if a person is watching TV
and unnatural, in the head, sound experience. These
using ConnectLine and a phone call comes in the lis-
problems only occur when streaming sound, so the
tener accepts the call by simply pressing the phone
new algorithms were developed specifically for im-
button on the Streamer. When the call is over the TV
proving streamed listening.
program streaming will resume.
Power Bass
ConnectLine provides benefit to hearing impaired
Generally, when listening with hearing instruments,
people by providing hassle free listening to external
sound is received both from the hearing instrument
audio devices and improving speech understanding.
receiver and through the vent, giving a balanced full
Speech understanding is improved by sending the
sound quality. The more open the vent is the more
signal to both ears and providing appropriate ear
sound, particularly low frequency sound, is able to
specific amplification through the hearing instru-
enter and leave the ear through the vent. Allowing
ments. Also, sending the signal directly from the
low frequency sound to leave the ear through the
sound source to the hearing instruments, without
vent reduces problems with occlusion when talking
the interference of background noise, improves the
and chewing, which is a really good thing. But when
signal to noise ratio and the sound quality. Lab tests
listening to streamed audio, sound enters the ear
showed significant improvements in speech under-
only via the hearing instrument receiver so less low
standing using ConnectLine and hearing instruments
frequency sound enters the ear and more escapes
versus hearing instruments alone . Field studies us-
from the ear. When streaming the lack of low fre-
1
2
3
Whitepaper
quencies can result in a thin or tinny sound quality
separate tones because the brain combines the har-
Music Widening
preference for listening to music, music with speech
particularly for open fittings. To solve this problem
monics with the fundamental. This gives the percep-
Another aspect of sound that is different when
and speech with Music Widening on versus listening
the Power Bass algorithm was developed; Power
tion of a louder richer sounding fundamental. When
streaming is that the sound seems to originate in the
without Music Widening. The results for all stimuli
Bass enhances low frequency sound, providing fuller
streaming the input signal is continuously monitored
head rather than in the surroundings- as one nor-
and settings are shown in figure 3. Participants re-
and richer sound quality when streaming.
to allow the selection of the appropriate bass boost
mally experiences. The location of a sound source
ported that the sound was more pleasant and that it
and harmonics. This gives an optimal bass sound.
can generally be identified quite accurately based
had a more open and airy sound quality with Music
on the differences between ears in level, phase and
Widening than without5. The results and participants
Power Bass uses a dual scheme to enhance the perception of bass. Low frequencies are increased as
The preferences for Power Bass settings were test-
pinna cues. For streamed audio these cues are miss-
reports show that Music Widening improves the per-
much as possible, and harmonics are added to en-
ed on ten people with mild to moderate hearing loss-
ing, which gives the perception that the sounds are
ception of space and sound quality when streaming.
hance the perception of bass. For soft input signals
es using open fit hearing instruments. Testing was
originating inside the head. This is fine for listening
the low frequencies are simply increased and no har-
conducted using a paired comparison test where
to speech, however, for music listening this can be
monics are added. For louder input signals the ability
participants were blind to the conditions. Speech,
perceived as being unnatural and boring.
to turn up the low frequency signal is limited due to
speech with background music and music alone were
the lack of head room, so harmonics of the low fre-
tested with various levels of Power Bass. Test re-
Music Widening is an algorithm that changes the
quency part of the signal are added to enhance the
sults showed that participants preferred Power Bass
acoustic cues when streaming to give the percep-
low frequency sound. Adding harmonics of the fun-
on and there was a significant preference for the
tion of a natural sound, as opposed to a sound that
damental, also known as overtones, creates a fuller
maximum Power Bass setting for all stimuli tested.
is in the head. The virtual cues are created based on
and richer sound because the brain fills in the missing
Results for all stimuli tested are shown in figure 24.
how sound is modified when listening in a real room.
fundamental when the harmonics are present. A vis-
These findings show that Power Bass significantly
When music is played in a room the music usually first
ual representation of the creation of harmonics of a
improves the sound quality for streaming with open
reaches the listener directly from the speaker, then
150 Hz tone is shown in figure 1. This example shows
fittings.
as the sound is reflected off the walls, it reaches the
listener again. Generally, the delay between the di-
that when shown visually the addition of harmonics
is obvious, however, when we are listening the only
PowerBass ON
Level in dB
PowerBass OFF
off
90
low/min
80
mid
70
high/max
1000
10000
Frequency (Hz)
Figure 1: Addition of harmonics to a 150 Hz pure tone. In the
visual representation the fundamental tone looks very different with the addition of harmonics, but the only difference in the auditory perception is that adding harmonics
makes the fundamental sound louder.
sound; an echo is heard if the delay between direct
and reflected sound is very long. Each reflection
that enters the ear introduces new level and tim-
% of trials setting was preferred
100
off
90
low/min
80
mid
high/max
70
60
50
40
30
20
10
0
Jazz
Classical
Speech +
Music
Music
music
Speech
Overall
Figure 3: Shows preferred level for Music Widening for the
11 participants. Overall results show a significant preference for Music Widening (p<0.05). If all stimuli had been
equally preferred the ratings for all four settings would be
around 25%.
ing differences between the ears. The differences
60
50
40
30
20
10
0
100
4
are combined in our mind and we only perceive one
100
% of trials setting was preferred
louder. We do not hear the addition of harmonics as
rect and reflected sound is so short that the sounds
Preference for PowerBass Settings
difference we can perceive is that the 150 Hz sounds
Preference for Music Widening
Jazz
Classical
Speech +
Music
Music
Music
Speech
Overall
Figure 2: Shows preferred level of Power Bass for the 10
participants using open fit hearing instruments. Overall
results show a significant preference for Power Bass(p<0.05). If all stimuli had been equally preferred the ratings for all four settings would be around 25%.
between the right and left ear are what give us the
Field Test Results with Agil and ConnectLine
impression of an external sound with a certain direc-
Lab test results with hearing impaired listeners
tion played in a certain type of room. These reflec-
showed that Power Bass and Music Widening im-
tions also make music sound richer and fuller. Music
proved sound quality by adding bass and space to
Widening creates the impression that music is being
the listening experience. After having found set-
played in a living room by generating the appropriate
tings for Power Bass and Music Widening , which
virtual cues.
improved the listening experience when streaming
we decided to test Agil Pro with ConnectLine in the
Music Widening was tested on eleven hearing im-
field to find out how it worked for people in their day
paired people with mild to severe hearing losses.
to day lives and how they rated the sound quality.
Participants made paired comparisons of four dif-
Testing hearing instrument settings in a realistic
ferent settings for Music Widening: off, low, mid and
environment is important because preferences in a
high. The high setting had the longest reverberation
highly controlled lab setting can differ greatly from
time, i.e. the longest time between first stimulus and
preferences in the real world.
the virtual reflection. Testing with hearing impaired
listeners showed that participants had a significant
5
Whitepaper
Experienced hearing instrument users with mild to
figure 4. Also, the sound quality for streamed music
severe hearing losses were recruited for testing.
listening was evaluated in the field test; participants
Participants were fit with Agil. The following styles
rated the bass, treble and overall volume for music
were tested: ITE, ITC, miniRite, Rite and BTE. Par-
listening. Participants indicated that the settings
ticipants tested one or several ConnectLine devices
were just right2. These results show that the default
depending on their needs. (This is why the number of
settings provide agreeable sound quality for music
participants who tested the TV Adapter, Cell Phone
and Landline Phone Adapter are different, see figure 5
for exact numbers for each condition.) Test settings
Sound Quality Ratings for Streamed Music
for Power Bass and Music Widening were selected
based on the overall preferences in Power Bass and
Music Widening lab tests, all other settings were
the default settings in Genie. Participants wore Agil
hearing instruments and used ConnectLine for 2-4
weeks. During the field testing participants filled out
questionnaires evaluating their perception of sound
quality and benefit with Agil and ConnectLine.
Volume
Treble
Bass
0
1
too little
2
3
4
5
6
7
just right
8
9
10
too much
Results from the field test show that experienced
listening, ratings are shown in figure 5.
hearing instrument users received significant ben-
Figure 5: Sound quality ratings when listening to music
with Agil and ConnectLine. Rated by 11 hearing impaired
people with mild to severe hearing losses.
efit using ConnectLine and Agil hearing instruments
for listening to cell phone, landline phone and TV2.
Preference ratings show an overwhelming preference for Agil with ConnectLine versus their own
Field and lab test results show that Agil with Con-
solution (hearing instrument alone or hearing in-
nectLine, Power Bass and Music Widening, provides
strument and t-coil); Field test results are shown in
excellent sound quality for streaming. ConnectLine
has the potential to benefit many hearing impaired
people. As a matter of fact, ConnectLine can improve
Field Test Results
100
Agil Connect+ better
90
No preference
% of participants
80
Own solution better
70
60
speech understanding in three of the six most important listening situations: landline phone, television and cell phone listening, reported in the most
recent Marketrak3. We need to stop underestimating
hearing impaired peoples’, particularly elderly hear-
50
ing impaired peoples’, need for connectivity and be-
40
References
1 Sjolander M. L., Bergmann, M., & Hansen
4 Minnaar, P. New Algorithm designed to enhance L. B. Improving TV listening for hearing aid users.
low frequencies in open-fit hearing aids. Hearing Hearing Review. 2009;16(11):44-47.
Journal. 2010; 63 (3): 40,42-44
2 Hansen, L. B. & Holmberg, M. 2010. Oticon Agil 5 Minnaar, P. Enhancing music with virtual sound Connect[+] Product test results. Oticon A/S, sources. Submitted to Hearing Journal.
gin giving them the best listening access possible.
30
20
10
0
0
TV
(N=17)
Cell Phone
(N=12)
Landline Phone
(N=11)
Figure 4: Results from a field test with Agil and ConnectLine.
Participants compared their listening satisfaction with Agil
and Connectline to listening solution they previously used.
Significantly more participants were satisfied with Connectline and Agil than their own listening solutions.
Copenhagen, Denmark, (unpublished data). 3 Kochkin, S. MarkeTrak VIII: Consumer satisfaction with hearing aids is slowly increasing.2010; 63(1): 19, 20, 22, 24, 26, 28 30-32. 6
7
People First
People First is our promise
to empower people
to communicate freely,
interact naturally and
participate actively