Assistive listening: reaching the people your PA never did
Roughly one in five adults has some degree of hearing loss. At a 500-person event that's around a hundred people, most of whom will not ask you for help — they'll just follow less of it than everyone else.
An assistive listening system (ALS) delivers sound from the source straight to a listener's ear, bypassing the distance, background noise, and reverberation that make amplified speech hard to follow.
It's the same structural problem as crowd overflow, at the level of the individual. A loudspeaker throws sound across a room and hopes it survives the trip. For a listener with hearing loss, it frequently doesn't — and turning it up amplifies the reverberation and crowd noise right along with the speech.
Where it's required
In the United States, the ADA Standards for Accessible Design require assistive listening systems in assembly areas — spaces where audible communication is integral to the use of the room — when audio amplification is provided. That covers theatres, lecture halls, courtrooms, places of worship, conference rooms, stadiums, and similar spaces.
The broad shape of the requirement:
- The number of receivers required scales with the seating capacity of the space
- A proportion of receivers must be hearing-aid compatible — typically via a neckloop for telecoil users
- Signage must indicate that assistive listening is available
The four kinds of system
Hearing loop (induction loop)
A wire around the seating area creates a magnetic field carrying the audio. Hearing aids and cochlear implants with a telecoil pick it up directly — no receiver to borrow, nothing to ask for, nothing to sanitise. Users overwhelmingly prefer it. It's also the most expensive to install, it's a permanent fixture, and it only serves people whose devices have a telecoil.
Infrared (IR)
Audio sent as invisible light to a receiver. Because light doesn't pass through walls, it's the standard choice where privacy matters — courtrooms, boardrooms, and cinemas with adjacent screens. Needs line of sight and struggles in daylight.
FM / RF
Radio to a body-worn receiver. Flexible, portable, works through walls and outdoors, moves between rooms. The same family of hardware as tour guide systems. Someone has to hand out, charge, and sanitise the receivers.
Wi-Fi / cellular to personal devices
Audio streamed to the listener's own phone. No receiver to request, no queue at a desk, and no visible marker that singles someone out. It reaches their own earbuds and hearing aids, with their own volume and accessibility settings already applied.
| Loop | IR | FM/RF | Personal device | |
|---|---|---|---|---|
| Needs a borrowed receiver | No (telecoil) | Yes | Yes | No |
| Install cost | High | Medium | Low | Low |
| Works outside the room | No | No | Limited | Yes |
| Multiple languages | No | Extra channels | Extra hardware | Yes |
| Discreet for the user | Very | Visible receiver | Visible receiver | Very |
| Requires a smartphone | No | No | No | Yes |
| Latency | None | None | None | Small but present |
Where personal-device audio honestly fits
It would be easy to claim streaming to phones is a drop-in replacement for a compliant ALS. It isn't, and you should be sceptical of anyone who tells you otherwise.
Accessibility standards were written around venue-provided receivers. A system that assumes every listener brings a charged, data-connected smartphone makes assumptions the standards deliberately don't. In most jurisdictions a personal-device system is best understood as a complement to a compliant system, not a substitute for one.
What it genuinely adds:
- Reach beyond the room. Overflow spaces, lobbies, and outdoor areas that no loop or IR install covers.
- Nobody has to identify themselves. The single biggest reason venue receivers go unused is that asking for one means announcing a disability at a desk.
- Multiple languages on the same infrastructure. Accessibility and translation stop being two separate procurement problems. For public agencies the second one carries its own federal obligation — see language access in emergencies.
- Events without a building. Outdoor, temporary, and touring events have no installed loop to fall back on.
- Their own settings. Whatever a listener has already tuned on their own device — volume, balance, hearing-aid profile — applies automatically.
Beyond compliance
Treating this as a checkbox misses the size of the audience. The people helped by better audio delivery include anyone with hearing loss, anyone listening in a second language, anyone with an auditory processing difference, anyone in an overflow space — and, frankly, anyone at the back of a noisy room. Designing for the hardest listening case improves the event for everyone in it.
Frequently asked
How many assistive listening receivers do we need?
It's a sliding scale tied to the seating capacity of the assembly area, with a minimum floor for small spaces and a required proportion that are hearing-aid compatible. Because the figures are set out precisely in the standard and are updated over time, check the current ADA Standards for Accessible Design (or your national equivalent) rather than relying on a summary.
Do we need a loop if we already have FM receivers?
Generally the requirement is for a system plus a compliant number of receivers, some of which are hearing-aid compatible — not for a loop specifically. Neckloop accessories are the usual way to make FM and IR receivers telecoil-compatible. Confirm for your building type and jurisdiction.
Does streaming to phones satisfy the ADA?
Don't assume it does on its own. The standards contemplate receivers the venue provides, and a phone-based system depends on the listener's own device, battery, and network. Use it to extend reach and improve the experience, and keep a compliant system in place. Get a professional read for your specific space.
What about live captions?
Captions serve a different and partly overlapping group — many people who are deaf don't benefit from amplified audio at all. Where captioning is required or expected, it's a separate provision, not something an assistive listening system covers.