Induction

[Daniel Postilnik]

Can anyone give me a quick and dirty rundown of what installing an induction loop system (for the hearing-impaired) typically involves, and how it is supposed to connect to the sound system? I read that these are used at concert halls. What kind of quality is possible with this method of signal transmission?

Thanks.

 

[Ivan Beaver]

Re: Induction

Can anyone give me a quick and dirty rundown of what installing an induction loop system (for the hearing-impaired) typically involves, and how it is supposed to connect to the sound system? I read that these are used at concert halls. What kind of quality is possible with this method of signal transmission?

Thanks.

I have never installed an induction loop system-we always used wireless receivers and a transmitter.

From what I understand it is simply a loop that goes all around the room in question.

The input to the amp for the loop is either an aux out of off the main send-depending on what sort of sound you are trying to send to the receivers.

The quality is designed to give speech for hearing impaired people-not to provide full fidelity response.

 

[Caleb Dueck]

Re: Induction

Can anyone give me a quick and dirty rundown of what installing an induction loop system (for the hearing-impaired) typically involves, and how it is supposed to connect to the sound system? I read that these are used at concert halls. What kind of quality is possible with this method of signal transmission?

Thanks.

Back in the old days, it was basically a wire antenna run around the perimeter of a seating area, under carpet, or something similar. Today, it's vastly more complex, especially in larger spaces. Sometimes under/in floor, sometimes in ceiling. What the walls/ceiling are made from, stud material, etc all come into play. It's similar to a pro sound system, where the design and install are custom for each space, as opposed to home theater where a TV and a couple speakers are 'installed'.

If you're a dealer for Listen or Williams or similar, contact them, they typically design with or even for their dealers.

 

[Daniel Postilnik]

Re: Induction

I have never installed an induction loop system-we always used wireless receivers and a transmitter.

The quality is designed to give speech for hearing impaired people-not to provide full fidelity response.

Ivan, is it possible that the technology has become more sophisticated recently? I spoke with an indoor cycling studio (music and speech at relatively high SPL) and they said they use an induction look system with great success, which would suggest something close to full fidelity response.

 

[Ivan Beaver]

Re: Induction

Ivan, is it possible that the technology has become more sophisticated recently? I spoke with an indoor cycling studio (music and speech at relatively high SPL) and they said they use an induction look system with great success, which would suggest something close to full fidelity response.

I really don't know-because like I said-I have never installed one and it is not part of my current job. Sorry.

 

[John Moore]

Re: Induction

google it, you will be amazed , also get a hold of Listen Tech or Williams Sound, they both make systems and can help with the layout and install...

 

[Jordan Lahr]

Re: Induction

We just installed one in our house, not sure how its hooked up to our PA or if its just fed through our room mics. When I get a chance I'll grab one of the headsets and hear how well it works.

 

[Ivan Beaver]

Re: Induction

We just installed one in our house, not sure how its hooked up to our PA or if its just fed through our room mics. When I get a chance I'll grab one of the headsets and hear how well it works.

Remember one thing-these systems are designed for the hard of hearing-NOT as IEM for people with normal hearing.

So things that would bother us (hiss0lack of HF etc) do not bother people who are hard of hearing.

 

[Rob Timmerman]

Re: Induction

Remember one thing-these systems are designed for the hard of hearing-NOT as IEM for people with normal hearing.

So things that would bother us (hiss0lack of HF etc) do not bother people who are hard of hearing.

Yep. And the big benefit to induction loops is that many are designed to work with the telephone couplers in hearing aids, so a person with compatible hearing aids may not need a receiver at all.

 

[Daniel Postilnik]

Re: Induction

Remember one thing-these systems are designed for the hard of hearing-NOT as IEM for people with normal hearing.

So things that would bother us (hiss0lack of HF etc) do not bother people who are hard of hearing.

What I'm concerned about is that the mix of the signal going to the induction loop in my case has some issues. We've got recorded music with live vocal in a group fitness class, and the instructors aren't great at setting the music at a level such that they can actually be heard, and sometimes the music isn't the best quality because it's a remix pulled from a youtube video, or the music is distorted because the instructors are trying to get more volume by boosting iTunes equalizers or the limiters are getting slammed...etc. However, patrons aren't complaining.

The question is, what is all that going to sound like through an induction loop?

 

[Dick Rees]

Re: Induction

What I'm concerned about is that the mix of the signal going to the induction loop in my case has some issues. We've got recorded music with live vocal in a group fitness class, and the instructors aren't great at setting the music at a level such that they can actually be heard, and sometimes the music isn't the best quality because it's a remix pulled from a youtube video, or the music is distorted because the instructors are trying to get more volume by boosting iTunes equalizers or the limiters are getting slammed...etc. However, patrons aren't complaining.

The question is, what is all that going to sound like through an induction loop?

It's not going to be anything I'd want to listen to...

 

[Art Welter]

Re: Induction

What I'm concerned about is that the mix of the signal going to the induction loop in my case has some issues.
The question is, what is all that going to sound like through an induction loop?

Like any other system: garbage in, garbage out, but the garbage will have a reduced frequency response and signal to noise ratio, and also can contain additional induced noise from bad lighting ballasts, transformers and other sundry emf transmitters.
Getting an even, strong (but not too strong) field strength from the coil important too, which can be complicated by all the things Caleb mentioned.

 

[Tim Padrick]

Re: Induction

Then there are the complaints of interference with electric guitars.

 

[Daniel Postilnik]

Re: Induction

Then there are the complaints of interference with electric guitars.

Fortunately there are no live instruments in our setting. Just playback and live vocals. We also stopped investigating this option because the lady pushing us to consider it runs an advocacy group for the hearing impaired, knows nothing about our company (despite claiming to), and doesn't seem to actually know that much about this technology.

 

[Jonathan Kok]

Re: Induction

Fortunately there are no live instruments in our setting. Just playback and live vocals. We also stopped investigating this option because the lady pushing us to consider it runs an advocacy group for the hearing impaired, knows nothing about our company (despite claiming to), and doesn't seem to actually know that much about this technology.

It should be noted that companies involved in 'assisted listening' systems have PERSONAL induction loop transmitters designed to work with the standard wireless receivers. These are small T-Coil transmitters that plug into the standard ALS receiver, which the user wears around his neck as a lanyard.
Williams Sound NKL-001
Listen Technologies LA-166

I'll also note that this article from Listen Tech makes some valid points, such as a)T-Coils aren't popular in North America (though becoming more so), b) Induction Loops are limited to a single audio source, and c) Induction Loops are typically much more expensive to implement than FM or IR systems.