Anyone have experiences with Audio Induction Loops? | Hacker News Reader

Anyone have experiences with Audio Induction Loops?

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60 pointsevolve2k46 comments

About a decade back I was writing embedded firmware for a telephone for the hard of hearing. We ran compliance tests to ensure the handset was compatible with T-coils. In the early days of say Bell 500 and Bell 2500 sets, the coil in the handset speaker was big, and naturally emitted enough for hearing aids to pick up. As speakers shrank, the size of the coils dropped, it takes active design analysis to make a handset that will work. IIRC, ANSI has a standard for this compliance, this link leads me to believe it was updated in 2019: https://ieeexplore.ieee.org/document/8906258

They are a pain in the arse to set up properly and you really need a (edit: very patient, thank you for putting up with all my sine tones, Tommy) deaf person with a suitable hearing aid to help you set it up. If the loop is the wrong length and has the wrong impedance you'll never get the amp balanced up properly, and you can't just take the installer's word for it.

Beyond that I have very little experience of them.

FWIW, it is also possible to get standalone induction receivers that you can plug headphones into, which can be useful for "is this working" checks (for example https://www.ampetronic.com/products/ilr3-audio-induction-loo...). However you really need someone with hearing aids to tell if it's useful or not.

I visit the theatre a lot: ~50 West End visits in 2025, plus several regional venues. It's amazing how many times I've had to abandon the hearing assistance system because it doesn't work well... too quiet, distorted, delayed, poor balance between voices and instruments. Sometimes it just isn't functional at all, and nobody's noticed.

While I'm on the subject: saying "it's a loud show, you'll be able to hear fine" is a bit like telling someone who's short-sighted but has no glasses that "it's a bright show, you'll be able to see". It's not just about volume, but clarity and understanding.

For the lecture theatre and classrooms at work, we've gone over to IR transmitters and a neckworn loop, which is apparently better for everyone. You can also just use it with IR headphones, which suits certain flavours of neurospicy.

Not a bad option for a lecture theatre, but it's worth noting that IR is line-of-sight and can be easily interrupted by people moving or the receiver twisting as you shift position. Multiple emitters can help with some of this, but there are still challenges.

I'll try and get a pic of the setup next time I'm down there. There are these kind of pyramid domes in the ceiling with emitters.

Hearing aids are at a frustrating crossroads at the moment, IMO. In my experience, a lot of the recent hearing aids don't seem to support induction loops. It often seems to be a choice between that or Bluetooth... and Auracast isn't ready yet.

I've had Phonak bilateral hearing aids for 5 years, and Starkey unilateral for ~5 years before that. None of those have supported induction loops.

Why is Auracast not ready yet?

A quick search suggests that most headphones and hearing aids don't support it yet. This will be your greatest problem - nobody can use it. This seems like the future though so you should probably install it in your venue and get a few headphones that do support it to test it and to borrow to those who need help.

That few support it implies that there are likely going to be implementation/interoperability bugs for a few more years at least - nobody knows how bad these will be. Maybe things will just work, but growing pains should not be a surprise.

They claim latencies as low as 40ms - this is unacceptably long for a lot of music applications. For listening to the sermon at church good enough, but people may noticed if you are singing along. I'm not sure if this will be an issue, but it is something to consider. You might need a different system though.

It's a chicken-and-egg thing. Not many devices have it, so not many venues install it. Not many venues have it (perhaps because they've invested in other systems), and there's no pressure to change until there are many people wanting to use it.

Also because everyone now carries a computer in thier pocket with a very intelligent microphone and Bluetooth card. Anyone looking at hearing aids afresh today would start with that tech as the backbone.

There are wifi-based systems (like Sennheiser MobileConnect or Williams WAVECast), and my experience has been universally awful. The latency is so high that if you have any ambient hearing you get an echo that makes sound impossible to understand.

If you're ever considering installing one of these systems, please think again. Or at least trial it with a real situation, so you know what the experience will be like for the users.

At the same time, those that have hearing aids often complain that T-coils aren't properly set up or turned on, even in public building where they are required to (at least in Norway).

"Yes, we have T-coils, but the person responsible for it isn't here right now, and no one here knows how to use it."

So, still quite a few limited factors to their actual usefulness in society unfortunately.

A friend who installs loops complains they are largely pointless, because in practice nobody with a hearing aid ever wants to use them. Apparently the quality of a good hearing aid magnifying the audio in the room is substantially better than an induction loop.

No hearing aid magnification comes close if the induction loop is properly installed and integrated with the PA system. With an induction loop it's as if the microphone is directly connected to the hearing aid.

Yes, but you only have the PA on that, not the ambient.

Yes, it's amazing how often hearing assistance systems are either unusable (due to bad sound, e.g. hiss or distortion or volume issues) or just flat-out don't work here in the UK.

> ... those that have hearing aids often complain ...

When I do sound at church, I always wish they would complain more. I assumed it was working, but one day found that the power cable for the loop system was not connected. I plugged it back in, and spoke to a hearing aid user about it and they said it hadn't been working for weeks. Why they (or all the other hearing aid users) hadn't mentioned it before I don't know...

And unfortunately, Auracast must be installed in the venue or Auracast is useless.

I just got my first pair of HAs in November and I opted for the T-coil enabled model. It also (already) has working Auracast (not just "available in a future firmware update" like the other mfgrs). The T-coil model was not much bigger than the one without, and it also had two buttons on each unit rather than one on the T-coil-less model.

411, "Loop systems" are hard-coded in the US's ADA (Americans with Disabilities Act) so they are not going away anytime soon. When Auracast does proliferate it'll be alongside loop systems; not a direct replacement. (Not at least until the law is amended and we all know how long that takes.)

My HA model is the Starkey Omega 24 RIC-RT (the `mRIC` is the smaller version of the same, sans T-coil).

I see them less and less. Recently an acquaintance got hearing aids and when asked about the T functionality (to listen to induction loops) they didn't even know about it.

You can use a 9V battery powered amplifier with a loop around your neck to make a tiny permanent magnet placed in your ear canal vibrate against your ear drum.

It doesn't generate hi-fi sound, but speech is remarkably clear. Great for magic tricks. Or cheating at exams I suppose.

Has this actually been done before? It sounds fascinating. I have seen accounts of people embedding tiny magnets in their hands but not their ears.

I believe “permanent magnet” here refers to an object permanently magnetised, not a magnet permanently embedded in the ear canal.

Not embedded, just dropped into your ear canal.

I bought it maybe 15 years ago on eBay, so it's nothing new.

Dare to tell what you used it for? Or would you risk loosing some degree or something if you speak about it?

Wow the kids with my new found gift of telepathy. Plugged it into an iPhone mini-jack.

It was meant to be part of a roulette wheel prediction computer that never came to full fruition.

Okay this is legit hilarious.

That's really cool, but the idea of sticking a magnet inside my ear gives me the willies. >shudder<

I think the copper ring around your neck a.la Will Smith in Wild Wild West may clue in the test proctor to some suspicious activities

It was very thin, sewed into a 'wife beater' undershirt. You wouldn't notice it even if you're looking at it. In fact I'm pretty sure it was sold for the purpose of cheating on exams.

I appreciated them in earlier hearing aids. Back when the programming of them was still average (voice focus tech was still infancy) they were a godsend. When I was in primary school and HA tech was super average, I had a mini version where a teacher would wear a mic and I had a receiver that went directly to my hearing aids. It was amazing being able to hear the teacher clearly over even average background noise. As mentioned some have gone with BT over induction loops which I can understand. However, on my Phonak, they are super disappointing range wise. As an aside the integrated mic in my Phonak is practically useless. Very disappointing given their cost of nearly $10k AUD.

This is a potential public good category that could be (mostly) provided at-cost or fixed profit by a multi-country non-profit consortia. Hearing aids and assistive devices are too damn expensive and proprietary, way too expensive for most poor, disabled, and elderly people worldwide.

Edit: I honestly don't know how I will function when I get older because I'm likely to be alone and blind from ARMD.

Amateurs in USSR 50 years ago made wireless and powerless headphones, which use wire lay on perimeter of room to transfer sound and power.

In headphones there is tiny coil.

It really work and very reliable, but result coil (size of room) have very large reactive resistance, so it is nearly impossible to transfer even high frequencies, only low (bass) and medium, so it workable for speech but music is heavily distorted.

Could you use multiple coils for different bands?

You could transfer different bands via different coils on different frequencies, but unfortunately, capacity of information channel is limited by frequency. Because of this, radio using high frequency waves as carrier (radio or light, or even some sort of invisible rays), not coil, and have hassle with some sort of modulation of waves.

This mean, you could not transfer more information than half of maximum frequency.

https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theore...

Very good channels with very high signal to noise ratio, could handle more bits than Shannon limit (on engineers slang "channel is ringing", such example is fiber channel).

https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theore...

Most modern research also consider some digital techniques of sound (information) compressing, like use LLM as (de)compressor (google llm compression algorithms).

they also made microphones work like this. place em behind the panels of sockets on the wires. some accounts of such devices being found can be found in the book Spy Catchers (by some ex MI5 science officer during cold war). pretty interesting tech!

I use a neck loop plugged into a hearing assist receiver with my hearing aids set to Telecoil. This eliminates having to install a Telecoil in the venue, but they must have a hearing assist system. My experience at church services is that sound is substantially better than using the hearing aids by themselves.

There is a reason most in the US are going to using a translation wireless system. Channel one is English, channel eight is Spanish (8-64 channels are available depending on the system you buy). Unlicensed FM transmitters also work well for this. You need to make sure you don't conflict with other nearby users, but that generally is easy (and if there is a possibility you should have an agreement to have your "Christmas pageant" on different days so you can borrow each others receivers for the busy time thus saving both of you money).

Auracast looks like the future of this, so make sure anything new you get supports that. Those so few systems support it don't expect much of it - you should demand this to ensure the manufactures know there is demand, long term it is better for everyone to use one standard.

A 20 year old friend recently had a hearing aid fitted. Despite the aid, audio quality remains crappy in many of the places we gather.

Curious around the technology and value of Audio Induction Loops.

Would love to hear anyone’s experiences, insights and thoughts on the tech.

One of those niche technologies that you don’t use, unless you do use it.

We have one in our church, as all churches in the UK are legally required to have I think (many other venues too). As another commenter said you can get separate receivers, so I got one at one time to help with audio quality for live streaming. The loop signal comes straight out of the church PA, so from all the microphones and so the audio quality was very good, but there was a lot of hiss. I don't know if that's always the case with induction loops. At one time it stopped working - someone cut one of the connections back to the loop amp - so I was able to test it, which is handy.

We have several people who depend on it, including the church organist, so we soon hear if it's not working. He says it's working really well.

My Grandmother says the one in her church (which is nearby) doesn't work well at all and she usually doesn't hear much. I'm not sure why. She also finds the one in our church good, so I think they must have some problem.

I would think it could be worth contacting someone in charge of the venue(s) if it's somewhere you go regularly. I would imagine it heavily depends on how the whole thing is set up though - quality of microphones etc. We have lectern mics, singer mic, lapel mics for priest and a wide field mic. on the altar, so pretty good coverage, and they all go into an auto switcher thingy. I think it would need to be set up by someone who at least half knows what they're doing.

> set up by someone who at least half knows what they're doing.

Finding someone like that is hard for many churches.

My experience is using a neck loop plugged into the venue’s hearing assist receivers. This eliminates the need to have Telecoil installed in the venue.

Wow the granddad of the chemistry professor of the Periodic Videos[0] youtube channel invented this? wild.

0: https://youtube.com/@periodicvideos

From this article, it seems one can be made using only the right coil of wire and an ordinary audio amplifier:

https://spectrum.ieee.org/a-diy-audio-induction-loop-for-the...

IIRC a lot of NYC Taxis have them? (or at least, a mark on the side saying "Induction Loop")

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