Film-Tech Forum ARCHIVE: Assisted Listening Devices

This is topic Assisted Listening Devices in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Ronda Fitzsimmons (Member # 1418) on 07-24-2013, 04:35 PM:

Any recommendations for something that will work simply and cheaply with both Dolby CP750 and Ultra Stereo JSD-60D?

Posted by Justin Hamaker (Member # 2165) on 07-24-2013, 04:46 PM:

We just installed an Ultra-Stereo system. We have CP750's in all of our auditoriums. The units give us assisted listening AND descriptive audio. The signal is transmitted by infrared to the headphones, so there is no need to select an auditorium. Also, it is very easy to add on closed captioning devices.

While we do not have JSD-60's at our cinema, I have to assume they would work just fine since both are from USL.

One point I would make it to not go cheap on the accessibility devices. You want something that will work reliably, and be appealing to customers. Also keep in mind that having working accessibility devices are a defense against an expensive ADA lawsuit. Although it is not law yet, it is likely that closed captioning and descriptive audio may be added to the ADA. Buying a system capable of both would be a prudent investment.

Prior to installing the USL system, we used an old Phonic Ear system. The customers would get headphones plugged into a receiver - similar in size to an iPod. The problem is we had to rely on the employee to ensure the device was set on the right auditorium. Plus, these devices were not very sturdy and burned through batteries pretty quick.

Posted by Justin Hamaker (Member # 2165) on 07-24-2013, 08:05 PM:

Thinking about this a little further, if you wanted to do this in an inexpensive way, you could get an off-the-shelf FM transmitter and a handful of transistor radios.

0.5W CZH-05B Long Range (10km) Dual Mode Stereo Broadcast Home FM Transmitter*Fashion Black*

We just purchased one of the units above to try out at our drive-in. It actually had very good range (about 1000 feet) and puts out a very good clean signal with just the little stick antenna it comes with. It would easily have enough range to cover an indoor auditorium.

Then use something like the radio lined below for the actual listening unit. This would give you a workable system for under $100.
Sony SRF-59SILVER (SRF59) Portable AM/FM Walkman Radio

The problem is you have to have a different transmitter for every auditorium, and a second for each auditorium if you want to do descriptive audio. This solution also would not provide you with the ability to do closed captioning.

Posted by Harold Hallikainen (Member # 5405) on 07-24-2013, 10:54 PM:

I doubt that FM transmitter is legal to use in the US. 500mW is way too much power with any antenna. Field strength limits for unlicensed transmitters on the FM band are
. here.

These transmitters are also supposed to be certificated by the FCC and have an FCC ID. web page

Harold

Posted by Brad Miller (Member # 2) on 07-24-2013, 11:28 PM:

As long as they have an FM transmitter that complies with Part 15 rules like this one, then they should be fine since there is nothing the FCC could do about it. (Plus it could be in stereo.)

Posted by Monte L Fullmer (Member # 2797) on 07-25-2013, 01:28 AM:

SONY has a system that connect to any processor that broadcasts audio (and for the visual impaired from the server) close captioning via WiFi.

You program the receiver to the auditorium for either or both closed captioning and audio prior to the issue to the patron.

It's quite the blessing for those of hard of hearing or visual impaired.

-Monte

Posted by Harold Hallikainen (Member # 5405) on 07-25-2013, 07:15 AM:

Speaking of the Sony system, USL makes a cup holder mount closed caption receiver that works with the Sony transmitter. It is the CCR-200.

Harold

Posted by Ken Lackner (Member # 1002) on 07-26-2013, 12:10 PM:

quote: Monte L Fullmer
SONY has a system that connect to any processor that broadcasts audio (and for the visual impaired from the server) close captioning via WiFi.

Not exactly. While the system does operate in the same 2.4GHz band that WiFi operates in (and therefore susceptible to potential interference from nearby WiFi networks), it does not use WiFi protocols. It's not like the transmitters are access points.

quote: Monte L Fullmer
You program the receiver to the auditorium for either or both closed captioning and audio prior to the issue to the patron.

Also not quite true. When closed caption glasses are connected to the receiver, the audio port (which is a standard 3.5mm headphone jack) is disabled. So you cannot use audio and captioning simultaneously.

Posted by Louis Bornwasser (Member # 3063) on 07-26-2013, 12:28 PM:

Expectation. In the US we expect to use a system that is IR. No tuning is required between rooms, since the walls stop all light. The Ultra Stereo is a good system that is reliable; certainly more than most.

In other countries, there is in place a loop system which is superior because most hearing aids come equipped with an on board loop receiver. You don't have to loan out anything. and there is little or no bleed over room to room.

Other systems work perfect;y well, but they violate the rule of expectations and require training the customer every time.

Another problem is that most hearing impaired customers are vain enough NOT to ask for the loan of equipment that, to them, is also unsanitary. They literally suffer in solence.

Posted by Gordon McLeod (Member # 33) on 07-26-2013, 12:58 PM:

One issue with IR emiters is interferance from LED and CFL lamps
In several locations we have had to use the Senhieser Green LED emiters

Posted by Sam D. Chavez (Member # 1841) on 07-26-2013, 01:41 PM:

Regards USL, the interference from lights is gone as of the introduction of the Model UPC 28 that does not operate on the 95 Khz band.

Posted by Harold Hallikainen (Member # 5405) on 07-26-2013, 02:58 PM:

Does anyone have experience with loops? All receivers are required to have a 3.5mm jack to drive neck loops, which provide an AC magnetic field, the same as a room loop. These work with hearing aids that have telecoils that are designed to pick up the stray AC magnetic field from telephone earphones. However, many hearing aids have an automatic T-coil switch. These detect the DC magnetic field from the permanent magnet in the telephone earpiece to enable the T-coil. Neck and room loops do not generate this DC field, so the hearing aid does not enable the T-coil.

You can place the HI headphones over the hearing aid to get both the DC and AC fields from the headphones, so the T-coils work.

More discussion of this is here.

I would like to hear anyone's experiences with loops.

Thanks!

Harold

Posted by Louis Bornwasser (Member # 3063) on 07-26-2013, 03:58 PM:

Contact Max Bell at Bell Theatre Services, London. He is my source on that technology; mandated by their National Health people.

Basically a large loop of #10 wire driven by a very low impedance audio amplifier, or so I am told. Louis

Posted by Gordon McLeod (Member # 33) on 07-27-2013, 01:40 PM:

If they changed the frequency does it require different headsets?
When i used the green ones we got cited by the canadian equivelent of ADA as standard IR hearing aids didnt work

Posted by Sam D. Chavez (Member # 1841) on 07-27-2013, 02:57 PM:

The UPC 28's require new headsets. They are on dual 2.3/2.5 Ghz so it's ready for visual narration.

Posted by Harold Hallikainen (Member # 5405) on 07-27-2013, 03:35 PM:

Oops! Slight typo there Sam! The IRH-280 headphones (which work with the UPC-28C) use 2.3MHz and 2.8MHz. By the way, captioning is transmitted as a frequency shift keyed datastream at 1.8MHz.

Harold

Posted by Steve Guttag (Member # 268) on 07-27-2013, 06:47 PM:

Almost nobody makes the 95KHz equipment anymore due to the interference issues. I think when CFCs came into common place, it just accelerated the issue. USL still offers the 95KHz systems since theatres normally don't have a light issue once the lights are down.