Product information

Phonak CROS II is a dedicated product for clients with an unaidable hearing loss on one ear. Featuring the unique Phonak Binaural VoiceStream Technology™, it wirelessly transmits the sound from the unaidable ear to a Venture hearing aid on the better hearing ear. The hearing aid receives the signal and plays it into the better ear. As a result a person with single-sided deafness (SSD) can hear speech from the side they have not heard from before.

CROS II is compatible to hearing aids in all performance classes using the Phonak Venture platform.

Battery size

Working current (mA)

Push button

Volume control

Nano coating

IP rating

Dimensions (L x W x D)

Weight

Compatibility

CROS II - 13

13

2.6

•

•

•

IP672

3.2 x 0.8 x 1.5 cm

(1.26 x 0.31 x 0.59“)

2.2 g (0.078 oz)

Venture RIC / BTE

1 IP57 indicates that the hearing aid is water resistant and dust protected. It survived immersion in 1m of water for 30 minutes and 8 hours in a dust chamber as per the IEC60529 standard.

2 IP67 indicates that the hearing aid is water resistant and dust tight. It survived immersion in 1m of water for 30 minutes and 8 hours in a dust chamber as per the IEC60529 standard. No traces of dust were evident within the housing.

Product description

CROS DemoHook

CROS SlimTube

CROS Tip

CROS II Hook

• Hook to hold CROS on the ear during fitting and demonstration• For demo purposes only• Included with any Phonak CROS and CROS II device replacing the CROS retentions

• Standard SlimTube for CROS devices• Available in left/right and four different lengths (0, 1, 2, 3)• Domes need to be attached. Available as open, closed and power dome in three sizes (S, M, L)

• Custom made earpiece for CROS devices• Available in left/right and four different lengths (0, 1, 2, 3)• Available in hard and soft material

• Earhook to attach a custom earmold with standard tubing to CROS II-13• Only available for the CROS II-13 model• Included with any CROS II-13 device or can be ordered separatly

Earpiece options (CROS II - 13 only)

Phonak Target™ 4.1 or higher (4.1 only for CROS II-13) iCube II, NOAHLink, HI-PRO, HI-PRO2

SoftwareInterfaces

When using iCube II, Phonak CROS II is active during fitting. Your patients can instantly experience the benefits of the CROS solution and provide feedback during the fitting session.

Fitting

Wireless Communication Portfolio

All wireless accessories can be connected and used with the hearing aid on the better ear.

If a streaming signal is received by the hearing aid, the streaming signal from CROS II is automatically put on hold. The connection to CROS II will be re-established automatically when streaming from the accessory is stopped.

The Phonak RemoteControl App is used in combination with ComPilot II or ComPilot Air II and extends Phonak hearing systems with providing more control and flexibility. It also supports all CROS II features and allows for convenient and independent control of the hearing aid volume and the CROS volume.

The RemoteControl App can be downloaded from the Apple App Store or Google Play. A demonstration mode is also available to assist clients in getting started.

Apple App Store Google Play

Colours

P1 P2 P3 P4

P5 P6 P7 P8

Sand Beige Amber Beige Sandalwood Chestnut

Champagne Silver Grey Graphite Grey Velvet Black

Hair & Skin

Key features

Demonstration of CROS II during fitting

When using iCube II, Phonak CROS II is active during fitting. This leads to a quicker and more precise fitting process since the patient can give instant feedback on the balance between the devices and the sound quality.

CROS II volume control

Increasing the comfort in noise, the CROS II volume control allows the client to individually adjust the volume of the CROS signal.

Unique Venture features on hearing aid

Venture features, including AutoSense OS, are available for the hearing aid on the better ear to create the best hearing performance.

Less power consumption

Thanks to the Venture platform, CROS II uses 30% less power compared to Phonak CROS.

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Beige

P9 Q1

Ruby Petrol

Fashion Traditional

Field Study News July 2015

Phonak CROS II Improved speech understanding thanks to binaural beamforming With the introduction of Phonak CROS II, a binaural adaptive beamformer is available in a Contralateral Routing of Signal (CROS) system, for the first time. The binaural beamformer creates a narrower beam that allows a listener to focus on a particular voice when in a noisy situation. The result is improved speech understanding. This study aimed to investigate speech understanding differences in difficult listening situations with two CROS generations from Phonak. The newer Phonak CROS II, provided more benefit when compared to the Phonak CROS, which has a monaural adaptive beamformer.

Introduction Speech understanding in loud and noisy situations is a big challenge, especially for people with Single-Sided Deafness (SSD) (Schafer et al. 2013). Previous CROS systems, which lacked a directional microphone, did not provide improvements in speech understanding in noise. The new Phonak CROS II, based on the Phonak Venture Platform, now features Binaural VoiceStream Technology™ which also includes the improved Speech in Loud Noise (SPiLN) program, either as an automatic feature or as a manual program. For the first time, people with SSD can benefit from the improved Signal to Noise Ratio (SNR) that is provided by binaural adaptive beamformers. The objective of this study was to provide evidence for improved speech understanding in noise by testing the adaptive binaural beamformer, Phonak CROS II, in comparison to a monaural adaptive beamformer, Phonak CROS.

Method Twenty subjects participated in this study. All subjects had a hearing loss in one ear, which derived no benefit from a hearing aid. Ten of them had normal hearing in their “better” ear (CROS group) and the other ten had a mild to severe hearing loss in their ‘’better’’ ear (BiCROS group). Subjects were fitted with a CROS transmitter on the unaidable ear and a hearing aid in the other ear. Table 1 shows the exact aids the two subject groups were fitted with.

Platform CROS group BiCROS group

Venture (V)

Phonak CROS II/ Phonak Audéo V90-312

Phonak CROS II/ Phonak Audéo V90-13

Quest (Q) Phonak CROS/ Phonak Audéo Q90-312

Phonak CROS/ Phonak Naída Q90-RIC

Table 1: The Venture and Quest hearing aids that were fitted to the CROS and BiCROS groups.

The Phonak CROS II aids were tested in the lab as well as for home trials. Phonak CROS (Quest) aids were tested in the lab only. All hearing aids were programmed according to the subjects’ individual hearing loss and the first fit recommended by the fitting software. The acoustic coupling varied from open or closed domes to c-shells, if a closed fit was needed, but was kept consistent across test conditions. The Oldenburg sentence test (OLSA), was used to measure the Speech Reception Threshold (SRT), i.e. the SNR which yields a speech score of 50% correct. The OLSA was carried out adaptively, starting with an SNR of 0dB at 65 dB SPL noise level. The subjects were seated in the center of a circle of loudspeakers. Cafeteria noise was presented from 90° and 270° azimuth, and speech material was presented from 0° azimuth. The hearing aids were set to different programs: The Phonak Audéo Q and Phonak Naída Q hearing aids were set to a manual Speech in Noise (SPiN) program with UltraZoom (UZ), the monaural adaptive beamformer and Phonak CROS aids were set to Real Ear Sound (RES). The Phonak Audéo V and Phonak CROS II aids had a manual SPiN program and a manual SPiLN program with StereoZoom (SZ) enabled in both aids. Table 2 shows the beamformer setting in the Quest and Venture hearing aids.

Phonak Field Study News | Phonak CROS II 2

Product Manual program Beamformer name Beamformer behavior

CROS II / Audéo V

Speech in Noise (SPiN)

UltraZoom / Real Ear Sound

Adaptive monaural

CROS II / Audéo V

Speech in Loud Noise (SPiLN)

StereoZoom / StereoZoom

Adaptive binaural

CROS / Audéo Q

Speech in Noise (SPiN)

UltraZoom / Real Ear Sound

Adaptive monaural

CROS / Naída Q

Speech in Noise (SPiN)

UltraZoom / Real Ear Sound

Adaptive monaural

Table 2: Beamformer settings for the different hearing aid combinations used in

the study.

In an extended part of the study, ten further subjects with a mild to severe hearing loss were fitted with the appropriate Venture based custom devices: CROS II-312 Custom and Virto V90-312. To compare the results to Quest, CROS-312 and Virto Q90-312 were used. The same tests including the set up described above was used. A test and retest of each hearing aid combination was performed, but no significant differences were found. The Shapiro-Wilk-Test showed a normal distribution of the data and therefore the t-test for dependent (correlated) samples was used for the statistical analysis. The p values were adjusted according to Bonferroni (the level of significance (α) was set to αα = 0.017).

Results The following graphs show the results for speech understanding measured with the OLSA. Two subjects of the BiCROS group were unable to perform the OLSA. One of these subjects relied on lip reading and the other subject had a hearing loss on the better ear that was beyond the fitting range. Figure 1 shows the SRT in dB for different aids and manual programs for the BiCROS subjects. For this group, the binaural adaptive beamformer of Phonak CROS II resulted in better SRT values than the monaural beamformer of Phonak CROS and CROS II aids. The average improvement of 3.8 dB over the monaural adaptive beamformer of CROS II was significant (p = 0.002, t-test).

Figure 1: Speech understanding in noise for BiCROS subjects (n=8) measured with the Oldenburg sentence test (OLSA). The SRT in dB is shown for Phonak CROS II (monaural (UZ/RES) and binaural (SZ/SZ) beamformer settings), and Phonak CROS. The boxplot shows the median, the first and the third quartile, the minimum and the maximum value. Lower values indicate a better performance.

Figure 2 shows the SRT in dB for the different aids and manual programs for the CROS subjects. No significant SRT differences between the CROS aids were detected. A possible explanation is that the CROS subjects were fitted with an open acoustic coupling. For the binaural adaptive beamformer, a signal with an improved SNR is provided at the output of the hearing aid to improve the speech intelligibility. When using an open acoustic coupling, direct sound leaks through the open ear and the improved SNR is limited due to a masking effect.

Figure 2: Speech understanding in noise for CROS subjects (n=10) measured with the Oldenburg sentence test (OLSA). The SRT in dB is shown for Phonak CROS II (monaural (UZ/RES) and binaural (SZ/SZ) beamformer settings)and Phonak CROS. The boxplot shows the median, the first and the third quartile, the minimum and the maximum value.

Figure 3 shows the SRT in dB for the group of subjects fitted with custom products. CROS II-Custom with the binaural adaptive beamformer shows a significant improvement of 4.3 dB (p < 0.001) over the monaural adaptive beamformer of CROS II-Custom. There was no significant difference between the monaural adaptive beamformers of CROS-Custom and CROS II-Custom.

Figure 3: Speech understanding in noise for BiCROS Custom subjects (n=10)

measured with the Oldenburg sentence test (OLSA). The SRT in dB is shown for

Phonak CROS II Custom (monaural (UZ/RES) and binaural (SZ/SZ) beamformer

settings), and Phonak CROS Custom. The boxplot shows the median, the first

and the third quartile, the minimum and the maximum value.

After one week of home trials, the subjects reported on their experiences with the Phonak CROS II. One subject from the CROS group said: “I could clearly hear and understand more compared to my current hearing aids and to without hearing aids. They sounded more natural and I did not even notice I was wearing hearing aids. This was what I have always been looking for”. Another subject from the BiCROS group said: “I was surprised by the hearing aids in a positive way. I was in a big room/hall with

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300 people and loudspeaker announcements, but the speech understanding was excellent in that situation. Other hearing aids I have worn often had to be fine-tuned, but this was not necessary with CROS II”.

Conclusion This study clearly demonstrates, that the binaural adaptive beamformer of Phonak CROS II outperforms the monaural adaptive beamformer of Phonak CROS and CROS II. With the binaural adaptive beamformer of CROS II, subjects showed a benefit objectively and subjectively when in a ‘speech in loud noise’ situation. Thanks to Binaural VoiceStream Technology™ and StereoZoom, people with SSD will benefit from significant improvements in speech understanding compared to using a monaural adaptive beamformer (SPiN). In summary, the proven performance of Phonak CROS II should improve life quality for people with SSD.

References Schafer, E, Baldus, N, D’Souza, M, et.al, 2013, Behavioral and Subjective Performance with Digital CROS and BiCROS Hearing Instruments, Journal of Rehabilitative Audiology, in press.

Authors and Investigators

Principal Investigator

Simone Ebbing completed her apprenticeship as a hearing acoustician in 2007. She obtained her Bachelor degree in Hörakustik at the University of Applied Sciences Lübeck in 2010. Since then she has worked at Phonak AG and currently leads the validation team.

Author Davina Omisore Audiology Manager, Wireless Connectivity Solutions, Phonak AG Davina.Omisore@phonak.com