Phonak Marvel Bluetooth range

Under 1st two heading at the page I referenced there’s a link: FCC-Approved Equipment Labels for Part 15 and Part 18 devices2

In the attachments list offered on the linked page, there’s a run-down of the usage of the labels and certification text that’s to accompany the logos. I thought the neat thing is that they consider what to do if the part is too small for a logo and the text, etc. There’s something about having an electronic label as an alternative.

I agree with you that it’s interesting that a BT logo is used in association with the Roger Pen radio frequencies and it would be interesting to know if the fccid site just decide to put it there or somehow Sonova had a reason to use it, i.e., the Roger Pen is really a classic BT device and that’s why you can have Roger Direct with the Marvels?! BT to BT? (sorry if I’m all mixed up on this-haven’t been following Roger Direct to Marvels very closely). If you had BT that only works between registered/licensed Phonak devices, can that get the BT logo? Doesn’t something that uses BT have to work with any other BT device that meets the respective opposite function (client vs. host)?

I agree with what rex-Hawaii has posted. My conclusion after going down the rabbit hole of technical jargon and manufacturer claims is that Phonak is using Classic Bluetooth at 2.4 GHz to send the multiplexed stereo signal to one hearing aid. Classic only allows one simultaneous connection. This means that the first aid must demultiplex the channels and send the left to the left, and right to the right. I think the problem comes in with Phonak choosing to use 2.4 GHz for this job too. That signal does not travel well through your head, and needs to bounce of hard surfaces near you to get to the other ear. If my assumption is correct then one hearing aid will drop out more frequently than the other. And if your body gets in between the phone and the first aid, then both can drop out.

Here is an article from Signia that kind of explains the issue. Brand X is Phonak Marvel.

Comparison of streamed audio signal quality: what matters in the real world10

From my understanding, Signia gets around this problem, but only partially. They use MFi low energy Bluetooth which can talk to both hearing aids at the same time. There is no need to send the signal from ear to ear. However, they still have to get it from your iPhone in your pocket to each hearing aid. So it is only a partial solution. I use the KS8 which is basically a Signia 7Nx. What I notice is that outside away from hard surfaces I get more frequent drop outs. And I notice that when the phone is in my right front pants pocked, I am more likely to get a left aid dropout.

Phonak comes right out and says they stream music to the right and send it to the left, for BT A2DP from the phone. I can verify it tonight (actually forgot my HA’s today!) Not sure what happens with iPhone, but Marvels aren’t known to support MFi audio.

I’ll try it tonight with the TV Connector. From my experience with disconnections and reconnections in the past, I think they’re independent with the TV Connector. Which led some to assume AirStream had to be BTLE but I argue that it can be any custom protocol that they could program on the Sonova chip (which promotes custom proprietary RF protocols).

And if anyone has stereo Roger features, it might be interesting to verify.