It is our experience that many AV or IT engineers are not up to date on recent hearing loop equipment development and not familiar with the loop standard, lack proper training and experience in installing loops to meet the IEC 60118-4 requirements.

Often times architects or contractors, when deciding on fulfilling the ADA listening requirements,  simply contact an AV company and have them install  an assistive listening system without really considering the option that best serves the people who will use the system... those with the hearing loss. This leads to many systems rarely or never used.

Although there are other options which we will discuss, a professionally installed modern hearing loop system will still out perform and simplify connection to the ALS (assistive listening systems).  A hearing loop turns hearing aids or cochlear implants into wireless loudspeakers that broadcast customized sound directly into the end users’ ears without the need for any additional equipment. Hearing loops are fully compliant with ADA without the use of any additional equipment.

IR (infrared) RF (radio frequency) systems require a neck loop to  connect to hearing aids or cochlear implants. WIFI and Bluetooth are not ADA compliant. WIFI is ubiquitous and Bluetooth is a one-to-one system. 

Other systems require the use of a neck loop which means: distributing and collecting the transmitters, maintenance, batteries and sanitization of the devices. There is some debate about the small chance of neck loops used with IR or RF systems interfering with pacemakers.

Hearing loop technology is the preferred assistive system endorsed by the AAA (American Academy of Audiology) and HLAA (Hearing Loss Association of America).

Hearing loops are the only ALS that have a sound quality standard IEC60118-4 for installations. The International Electrical Code is recognized worldwide.

With a hearing loop, no one knows, except the listener that they are connected to the hearing loop thereby the user maintains their privacy and dignity. People are reluctant to seek out the other types of assistive listening devices thus they are not often used.

Initially hearing loops may appear to be more expensive but when you consider they can serve every seat in the house hearing loops are much more cost effective the others when comparing cost per seat. Hearing loops are on and working when the PA system is on. There’s nothing more to do.

Lets discuss the different options:

Induction Hearing Loops

• Operates at audio frequencies between 110HZ thru 5000Hz created by a magnetic field.
• Do not operate on a radio frequency or carrier frequency in the GHz or MHz range.
• No interaction between the 2 systems.
• No interference with wireless mics although humbukker guitar pickups may create a buzz but professional installations can prevent this.
• Professionally installed loop systems adhere to international standard IEC60118-4 induction loop standards, which assures there are: "no hot spots, cold spots or no spots" throughout the looped area.
• Meets all ADA compliancy: Where all seats in an assembly area are served by an induction loop assistive listening system, the minimum number of receivers required by Table 219.3 to be hearing-aid compatible shall not be required to be provided.

There are several hearing loop designs:

A perimeter loops - which is a loop encircling the room. Can work in smaller venues depending on the structure.

A figure 8 design - cover the room in a figure 8 pattern. Can work in smaller venues depending on the structure.

Phased Array designs - the most complicated installation and generally used larger venues.

A professional installer will know which system is appropriate after a site visit and test loop is run and will be able to design the proper loop installation.

RF System (frequency modulated)

• Consists of a transmitter and receiver.
• Operates on a radio wave frequency.
• Operates out to about 50 feet which after this distance there may be delay.
• Can connect to hearing aids and cochlear implants with a T-coil (telecoil) but must use a neck loop.
• Connectable to a body worn device and to headphones - good for people who don't use hearing aids. Must coordinate with venue prior to performance. Make sure batteries are fresh.
• Meets ADA compliancy but must use a neck loop to connect to hearing aid or cochlear implant. There is some debate about the small chance of neck loops interfering with pacemakers.
• Must be a certain amount of receivers available per venue size to meet ADA compliance depending on venue size.
• Sometimes you have to hold a neck loop up in front of you to get a good signal

IR System 

• Uses infrared light, same technology as a TV remote.
• Consists of an audio source, an infrared transmitter and a listening receiver.
• Anything can block the light ray severing the transmission of sound, I.E. someone walking by or someone’s head in front of you. Often used in courtrooms where sound can not escape.
• Can connect to hearing aids and cochlear implants with a T-coil (telecoil) but must use a neck loop.
• Meets ADA compliancy but must use a neck loop to connect to hearing aid or cochlear implant. There is some debate about the small chance of neck loops interfering with pacemakers.
• Each venue must provide a certain number of receivers to meet ADA compliancy depending on venue size.
• Sometimes you have to hold the neck loop up in front of you to get a good signal

Bluetooth/WIFI

• Does not meet any ADA compliancy. 
• Need cellphone to connect.
• Range of 30' (Bluetooth).
• Not connectable directly to hearing aids or cochlear implants.
• Audio Latency - have a noticeable lag time from the voice to the ears. 
• Too many users can slow down the transmission (wifi).
• Will everyone know how to connect?
• No guarantee of frequency response range to assure clear speech between 100Hz thru 5000Hz.
• WIFI may not be powerful enough for larger areas.
• People may be looking at their phones more than the program.