Updated: Oct 31
Over the months of August and September, I received a relatively high number of middle-aged patients for hearing aid consultation. Not surprising that Bluetooth streaming was one of the biggest criteria of selection for almost all of them. This article is my own reflection on Bluetooth streaming and hands-free calls of some of the premium hearing aids and how they rank on Bluetooth streaming in my experience. I tested Widex Moment, Oticon Real, Starkey Evolv Ai, Signia Pure AX, Resound Omnia and Phonak Lumity for their Bluetooth range in a living space.
As an audiologist, I try every premium hearing aid as soon as they are available in the market so I can provide practical and unbiased advice to my patients.
I love music. Also, I love listening to podcasts while commuting to work. I have binaural tinnitus as well, so you can imagine that I am heavily dependent on Bluetooth connectivity and streaming for listening to music, my favourite podcasts and managing my moderate tinnitus through sound management and masking.
Let's have a brief on Bluetooth technology.
What is Bluetooth?
Bluetooth is a low-power wireless communication technology that uses a 2.4 GHz band frequency to send and receive information between two devices.
What factors affect the range of Bluetooth?
The range of Bluetooth can be more than a kilometre to less than a meter (more details here). There are 5 main factors that determine the effectiveness and reliability of Bluetooth communication between two devices:
transmitter antenna gain and
receiver antenna gain.
What factors affect the range of Bluetooth in hearing aids?
Out of the 5 factors mentioned above the transmit antenna gain and transmit gain are at the side of the transmitter, in the case of hearing aids will be your smartphone that is sending the music streaming to your hearing aids, for example.
The receiver sensitivity is a key factor in the effectiveness and reliability of the streaming to your hearing aids through Bluetooth. The path loss becomes critical when the transmitter (in their case your smartphone) is not in direct sight of the hearing aids, e.g. you have put your smartphone in your pocket, in your bag or in a different room. In such a condition, you must have experienced that as you turn your head the reception is interrupted in one ear versus the other one. As a matter of fact, your head becomes the biggest barrier between the transmitter and the hearing aid and the received streaming signal is masked and corrupted.
Until recently the hearing aid manufacturers did not consider the receiver antenna in the design of Bluetooth streaming through hearing aids. Two hearing aids hit the market in 2023 that have paid attention to improving the reliability of Bluetooth streaming by considering the receiver antenna in their design.
Resound Omnia - Resound GN has successfully used the wire of the speaker in their latest model Resound Omnia as the receiver antenna. Such simple innovation almost doubled the range of Bluetooth connectivity from 12m to 25m in an open field. Please see the video clip below. See Resound Omnia here.
Starkey Evilve Ai Bluetooth CIC - In the same approach Starkey also used the retainer wire of its latest invisible Starkey Evolv Bluetooth CIC as the receiver antenna to improve the Bluetooth connectivity. The result is magnificent, especially knowing that generally speaking the custom made hearing aids have poorer Bluetooth connectivity compared to RIC and BTE hearing aids, simply because most of the electronics in the hearing aids are deep inside the ear canal makes a bigger path loss for the sent and receive Bluetooth signals. See the product here.
How do hearing aids rank in their Bluetooth range?
In an in-house effort, I used a simple set-up in the clinic to understand how the available hearing aids in the market rank in terms of their range of Bluetooth. Below is the results:
Starkey Evolv Ai, Starkey Genesis, and Widex Moment - 7mt
Signia Pure AX and IX, Rexton BiCore and Resound One - 8mt
Oticon Real - 9mt
Resound Omnia - 12mt
Phonak Lumity - 15mt