Journal Article, Research Study, Sound Quality. Directionality

Directional microphones reduce background noise when the desired sound and the sound considered to be noise are spatially separated.Directional microphones reduce background noise when the desired sound and the sound considered to be noise are spatially separated. Those used in hearing aids are typically designed to enhance sound in the look-direction of the hearing aid user and have shown to be most effective in suppressing noise from behind.

While directional systems that rely on dual microphones on a single hearing aid are most common, current hearing aid technology with ear-to-ear audio streaming can support directional systems that incorporate all 4 microphones on bilaterally fit hearing aids to form narrow directional beamwidths.

This paper describes a companion study that examined how measured beamwidth translates to behavioural performance in speech recognition in noise.

Journal article, Research study, Remote fine tuning, Apps

A field trial at NAL with 30 experienced hearing aid users tested hearing aid outcomes and usability of the ReSound Smart 3D app and Assist remote services, as compared to in-person follow-ups.

Initial fitting procedure was the same for all patients, but only 15 patients tested the app and Assist. Of these, 12 patients requested fine tuning via the app, with 11 patients using it successfully (92%). Questionnaire and exit interview data from the 11 patients who successfully used the feature suggested that, while not perfect, the app was easy to use and that it was a good way to receive fine tuning services.

Outcomes measured on all patients at 6 weeks post- fitting via speech in noise testing, APHAB and SADL showed no difference between patients using the app/remote services and those who did in-person follow up visits.

Journal article, Research study, Sound quality

In this field trial, 23 patients who had recently purchased ReSound LiNX2 RIEs at one audiology practice were refit with ReSound LiNX 3D RIEs.

They wore the new ReSound LiNX 3D devices for 4-6 weeks.

QuickSIN results were identical between hearing aids, but average satisfaction with sound quality measured via the SSQ12 and Hearing Aid Satisfaction Survey was significantly higher for LiNX 3D over LiNX 2 in various real-world listening situations.

70% of patients stated a preference for the sound quality of ReSound LiNX 3D and 65% opted to pay a 10% markup from the LiNX2 price to upgrade to LiNX 3D devices.

White paper, Sound quality, Wireless streaming

This study conducted by an independent laboratory examined sound quality preferences specifically for sounds streamed from an iPhone for multiple premium hearing aids.

16 hearing aid users evaluated samples of streamed speech and music recorded from ReSound LiNX Quattro, LiNX 3D and five other premium hearing aids.

The recordings were customized to each tester’s hearing loss. ReSound LiNX Quattro was most preferred for both streamed speech and music, with ReSound LiNX 3D and one other hearing aid brand slightly but not significantly worse than ReSound LiNX Quattro.

Aspects of sound quality attributed to the ReSound devices included full dynamic range with clear details, a balanced bass/treble mix and lack of a hollow or restricted frequency response.

Journal article, Directionality, Field study

This study examined performance and preference of asymmetric directionality settings in patients with differing SIN abilities. 28 men with symmetric SNHL – 16 of whom had symmetrical SIN abilities in each ear, while 12 had a left ear SIN advantage – completed the study.

Patients with asymmetric SIN abilities performed more poorly on SIN tests than the symmetric SIN group – and asymmetric directional settings affected their SIN scores differently than the symmetric SIN group.

However, the asymmetric SIN group’s real-world experience with asymmetric directionality was not significantly impacted by settings for omni/directional ears.

This suggests that patients with asymmetric SIN abilities can still benefit from the advantages that asymmetric directionality provides. 

Journal article, Teleaudiology, Apps, Field study

Fourteen tech-savvy hearing aid users compared in-person and remote fine-tuning appointments in this field study from the Hearing Center in Oldenburg, Germany.

Each participant experienced both a remote fine-tuning session using ReSound Smart 3D and ReSound Assist and a face-to-face fine tuning over a wear time of 3 weeks.

The order of each fine-tuning appointment was counterbalanced across participants. The fine-tuning method did not significantly impact average SIN scores, IOI-HA scores measured at each visit.

The participants rated ReSound Assist as highly usable, both after this short 3-week trial and after an additional 4 weeks of wear time for 10 participants who owned their own compatible smartphone.

Journal article, Remote microphones, Apps

This study examined how different remote microphone technologies may affect speech recognition in a simulated classroom setting. 15 experienced hearing aid users with moderate to severe HL were fitted with ReSound LiNX2 hearing aids. 

Speech recognition in quiet and in noise using the AzBio was measured using hearing aids alone, hearing aids + fixed-gain remote microphones with omnidirectional (ReSound Mini Mic) and adaptive directional mics (ReSound Multi Mic) and hearing aids + adaptive-gain, adaptive directional remote microphone system (Roger Touchscreen with Roger X receivers).

Results showed that all remote mics were superior to hearing aids alone in noise, and that the adaptive gain system (Roger) performed best in the worst SNRs, while both adaptive directional remote mics (Multi Mic, Roger) outperformed the omnidirectional Mini Mic in more moderate SNRs. These results can help clinicians find the best solution for patients while balancing performance, convenience and cost. 

Journal article, Real ear measurements, Open fittings

Variability in real ear measurements (REM) is a real issue that can affect the accuracy and practical application of hearing aid fitting verification. This study examined how different types of hearing aid fittings, including the popular open fitting, can affect the variability seen in REM.

Insertion gain measurements were conducted on 20 ears using 5 different conditions – BTEs with standard tubing and custom earmolds, BTEs with thin tubes and open and tulip domes, and RIEs with open and power domes – and 2 different audiologists who measured each condition twice.

None of the variation in REM between the 2 testers, the 5 hearing aid conditions and the 2 test-retest sessions were found to be significant. This shows that REM is reliable in open fittings, as long as care is taken to ensure appropriate REM procedures, especially proper probe tube insertion.

Journal article, Directionality, Field study

While benefits of asymmetric directionality had been demonstrated in laboratory settings, this field study set out to determine how listeners in the real world may function with an asymmetric directional fitting. 

12 experienced hearing aid wearers wore their own hearing aids (represented by various brands) in two counterbalanced at-home trials – 1 program with bilateral omnidirectional microphones and 1 program with asymmetric directional (1 ear omni, 1 ear directional). They logged their hearing aid use and ease of listening in each microphone mode. 

The participants did indicate greater ease of listening for asymmetric mode, though this was only in situations where directional microphone use would be expected. They did not show a strong preference for either microphone mode, meaning that the participants were able to benefit from the asymmetric directional mode without impacting satisfaction for environments where omni is typically preferred.

Journal article, Environmental classification, Datalog, Field study

This observational study examined the acoustic environments experienced by older adults using ReSound hearing aids, over both a 6-week and 13-month trial period.

The data collected by the hearing aids suggested that the older adults spent an average of 60% of their time in quiet or one-on-one speech situations, which matched closely with measures of social activity conducted before the start of the trial.

It provided evidence that sound environmental classification is accurately identifying the acoustic situations patients are encountering, due to the high correlation of datalogging obtained in left and right hearing aids for each listener. This, in turn, helps to ensure the automatic processing features of the hearing aid are activating in their intended environments. 

Journal article, Directionality, Speech recognition

Asymmetric directionality utilizes both omnidirectional and directional settings in diffuse noise environments to improve audibility of desired signals while also preserving environmental awareness. This study looked at how different speech and noise configurations can affect performance in an asymmetric directional program.

Two noise conditions were tested – speech in front with diffuse noise behind the listener and speech on the right side of the listener with diffuse noise on the left. Bilateral directional was best for speech in front, while directional mode towards the noise source was more beneficial than directional mode towards the speech when speech was on the side.

This study doesn’t replicate real-world scenarios, but rather shows the importance of adaptability of an asymmetric microphone mode. While did not always show the greatest benefit, the ability of the program to adapt to different microphone configurations can help encompass a wide variety of dynamic noise environments.

Journal article, Sound quality

Sound quality is one of the most important drivers of patient satisfaction with hearing aids – but defining sound quality, and what makes good, is very subjective.

A new methodology to better assess sound quality attributes of hearing aid output was developed by an independent lab. Hearing-impaired listeners were trained to assess various aspects of sound quality, such as naturalness, bass/treble mix, reverberation, loudness and distortion.

They then assessed passages of speech and music recorded through six premium hearing aids. ReSound hearing aids were top-rated for sound quality over two generations of hearing aid products.

High ratings for sound quality were associated with high levels of naturalness and low levels of distortion.

Journal article, Open fitting, Fitting protocol

ReSound was a pioneer in the open fitting concept with the release of ReSound Air in 2003.

This paper discusses the concept of open fittings in detail and is a good resource for background information on open fittings.

The reasons for developing open fittings, such as reduced occlusion and improved comfort and cosmetics are discussed, along with how issues with open fittings are mitigated.  

Journal article, Real ear verification

Real ear measurements (REM) are a crucial part of verifying hearing aid fittings. This article discusses how stimulus type and hearing aid settings can impact REM results.

Pilot data measurements with three hearing aids demonstrated that when a speech stimulus, such as the ISTS, was used for REM, the hearing aid features used in everyday listening programs could remain activated and have less than a 2 dB effect on REM output.

Pure tone or speech-shaped noise, on the other hand, caused differences in output depending on what features were activated and how long the stimulus was presented. This variability also depended on hearing aid brand. 

Journal article, Remote microphones 

Remote microphones are a robust and cost-effective method for maximizing speech recognition in noise, but it isn’t always clear how to best use this technology in everyday situations.

This article discusses current evidence in favor of remote microphone use. In addition, it suggests tips for helping patients get the most benefit from remote microphones in restaurants, cars, lecture halls, places of worship and large group meetings. 

Journal article, Wireless streaming, Remote microphones, Teleaudiology, Apps

This article summarizes the many ways assistive devices can enhance patient’s hearing aid fittings, including wireless accessories, apps and remote fine-tuning services.

Evidence addressing the improvements these technologies can provide are presented, plus practical tips for demonstrating and incorporating these technologies into the patient’s fitting.

Journal article, Cognition, Directionality, Localization

Hearing aid signal processing should support the brain’s natural functions.

This paper describes two processing features– Binaural Directionality and Spatial Sense – that are important for providing the most advantageous auditory input to the individual, when higher processes and cognition are considered.

Journal article, Directionality, Remote microphones

This article discusses the history of directional microphones in hearing aids and how each generation of technology builds in complexity from previous applications.

Although many further developments have been implemented since the publication of this article, it gives a good summary of the multitude of directional options commercially available in hearing aids and shares important tips for using each type of directional mode in patient fittings.

Journal article, Teleaudiology, Apps

Hearing care professionals can gain valuable insights into the amount of time they spend on appointments each day, but most clinics don’t have the ability to step back and examine this information. This article analyzed anonymized appointment data for over 80,000 patients in a large hearing aid clinic over a 9-year period.

Fine tuning appointments represented nearly 30% of all appointment types, with nearly all taking 30 minutes or less time to complete. However, most clinicians and patients know that much more than 30 minutes is spent in total when accounting for travel and wait times.

Insights like these, along with solutions for increasing efficiency and convivence, can help inform other clinicians regarding their own practices.

Journal article, Teleaudiology

The healthcare landscape has shifted in recent years, with patients acting more as consumers than ever before. Telehealth tools have developed in part due to this change, but it can be difficult to navigate how these tools can be best implemented in hearing healthcare practice.

This article discusses how telehealth is likely to impact hearing healthcare and possible ways these tools can assist clinicians in providing the best care for their patients.

Journal article, Teleaudiology, Apps

Telehealth can help increase patient satisfaction with healthcare services, including in the field of hearing healthcare.

Recent teleaudiology tools that have emerged are described, specifically ReSound Assist remote fine-tuning service via the ReSound Smart 3D smartphone app. Evidence supporting the use of teleaudiology is also discussed.

White paper, Remote microphones, Real ear verification

This paper describes how ReSound remote microphones can be verified via electroacoustic measurement. Step-by-step instructions were created based on guidelines developed by AAA and ASHA for verifying FM systems.

Readers are instructed on verifying transparency, SNR advantage and maximum output using the Otometrics Aurical HIT. Tolerances for each measurement and suggestions for adjustments are also discussed.

Journal article, Fitting protocol, Real ear verification

Protocols for fitting and fine-tuning hearing aids have been developed by multiple experts in the field, but little has been discussed about a fitting “philosophy” – the more personal aspect of providing hearing care that is shaped by the hearing care professional’s experience and what each patient beings to the table.

This article delves into concepts relating to fitting philosophy and how hearing care professionals can develop their own patient-centered models for practice and how it can affect hearing aid fittings.

Journal article, Fitting prescription, Fitting protocol, Real ear verification

The gain or output display in fitting software does not necessarily match closely with the actual output in a patient’s ear.

This is due in part to the COupler Response for Flat Insertion Gain (CORFIG), which must convert coupler gain to simulated real ear gain, as well as the issue of creating the “average” real ear in the fitting software.

Details on the effects of these and other variables on simulated real ear view are discussed.

Journal article, Pediatrics, Remote microphone, Wireless streaming

Children with hearing loss benefit from use of assistive technology, such as wireless remote microphones, both in and outside of the classroom.

As children age and become teens, they face ever-changing challenges in the use of remote microphone technology.

This paper discusses how hearing healthcare professionals can be aware of those challenges and discusses how today’s digital wireless technology can help overcome them.

White paper, Severe-to-profound hearing loss, Case studies

The ReSound Enzo 3D hearing aid was developed to meet the many needs of patients with severe-to-profound hearing loss.

It is part of a hearing ecosystem that includes wireless accessories, ReSound Assist remote fine tuning and compatibility with Cochlear CIs.

This paper presents three ReSound ENZO 3D users and illustrates how particular aspects of this unique hearing aid have enriched their lives.

Journal article, Pediatrics, Remote microphones

Classroom environments often present high levels of background noise, reverberation, and a long distance from the speaker of interest. This places the hearing-impaired student at a significant disadvantage compared to normal-hearing peers.

The ReSound Multi Mic is a unique solution that meets the needs of students and teachers as well as offering an affordable solution outside the classroom.

It can be used alone or integrated with existing FM or DAI equipment, such as the Roger universal receiver.

Solutions for implementing the Multi Mic are discussed.

Journal article, Fitting protocol, Mild hearing loss

Patients with mild hearing loss present with unique challenges.

They are a diverse group who may experience significant problems with communicating in noise or who may not be aware of any hearing issues at all.

Pursuit of treatment for this patient population requires expectation management, investigating their hearing handicap and understanding the amplification options that can work best for them. 

Journal article, Remote microphones, Cochlear implants, Bimodal users

Bimodal CI users can benefit from the use of a remote microphone in noisy situations but were previously only able to stream sound into one ear.

Now, the ReSound Multi Mic can stream sound into both ears via the hearing aid and Cochlear CI.

This investigation into remote microphone and bimodal streaming benefit found that CI patients gained significant SIN advantages by using a remote microphone with their CI and by having the signal streamed into both their CI and HA.

They found an average of 2 dB bimodal advantage. 

Journal article, Audiogram+, Fitting protocol, Real ear verification, Localization, Cochlear implants, Bimodal users

This study investigated how fitting method may impact outcomes in bimodal patients.

Bimodal Cochlear CI users were fitted with ReSound Enzo using two techniques for loudness balancing – broadband vs. narrowband – and two fitting prescriptions – Audiogram+ and NAL-NL2.

Average REAG showed no significant difference in gain after all adjustments had been made.

Fitting method also had no impact on speech understanding in quiet or noise or localization abilities, although patients did show significant benefit for speech in noise when fitted bimodally versus CI only.

Journal article, Directionality, Severe to profound hearing loss 

Directional microphones have long been utilized in hearing aids to improve speech understanding in noise, but the implementation of directional microphone modes can be vastly different and likely have different effects on listeners. This study examined how ReSound’s Binaural Directionality III feature – which is designed to take advantage of both omni- and directional microphones in noise – impacted SIN understanding compared to 2 binaural beamforming features commercially available in hearing aids from other brands. 

10 listeners with moderate hearing loss, and 7 with severe to profound loss, were fitted with the three hearing aid brands and completed an adaptive SIN task in three listening setups -speech from the front, from the side and from behind the listener. Binaural Directionality III significantly outperformed the other 2 brands when speech was either to the side or behind the listeners. One brand of binaural beamformer was better for speech in front than ReSound, but only for the moderately impaired listeners.

Journal article, Wireless streaming, Phone use, Severe-to-found hearing loss

When direct-to-hearing aid MFi streaming became available, the opportunity for patients to benefit from added visual cues during phone calls via FaceTime also became a reality. This trial examined how various phone calls techniques used with hearing aids might affect speech recognition for hearing-impaired listeners.

15 listeners with severe-to-profound hearing loss attempted a speech in noise task with audio routed through an acoustic phone, through a wireless PhoneClip+ device and through direct MFi streaming with and without FaceTime. Unilateral versus bilateral streaming was also investigated. Streaming the phone call via any method over acoustic greatly improved understanding in noise, as did bilateral streaming over unilateral.

The visual cues provided by FaceTime were also of significant benefit, with a 23% average improvement over audio only, even when using unilateral streaming.