Case Study
George Street Playhouse: Assistive Listening System Install
How iProbe's install of a new assistive listening system enhances the audience theatre experience in New Brunswick, NJ

the stage and seating at George Street Playhouse.

the client's need

we helped with

• the install of an assistive listening system (ALS)

iProbe Client Testimonial

the challenge

the George Street Playhouse ia a leading New Jersey live theatre located in New Brunswick.

the theatre was to receive a grant to upgrade the assisted listening system in their 350 seat proscenium theatre. Their ALS system was very noisy and could not take much level. The theatre's audio engineer, Ted Crimy, really wanted to improve that and took charge of sourcing a new system.

the audio engineer reviewed FM and IR options and through fraught with debate on which is better, decided FM was the way to go as before his time the space had an IR, but apparently the line of sight issues really made it problematic. Ted started to review the theatre's options for a reliable ALS system to transmit and receive the audio.

the solution

in order for the hearing impaired theatre audience to clearly hear the performances, the George Street Playhouse reached out to iProbe regarding the purchase and install of an FM assisted listening system. For the theatre’s complete system, two distinct feeds are to be transmitted on two different frequencies: one for assisted listening, the other for audio description to the visually impaired. The theatre wil not always use the two transmissions simultaneously and therefore one transmitter will serve also as as a backup of the other.

ALS system selection

iProbe proposed a Listen Technologies 50 Ohm system in the 72 Mhz band. After the grant money came through and early 2016 the Theatre was ready to move forward. The system consisted of two desktop transmitters with antennas and 30 wireless receivers in the 72 Mhz band along with a mix of headphones, neckloops, rackmount accessories and cases.

after selecting the FM system, the next step was a site survey by the iProbe install team. The team's RF Engineer used a spectrum analyzer to scan the environment to determine the antenna placement location for optimal system performance. After the site survey, the equipment was ordered with the manufacturer and the install team came back and installed the system following the RF Engineer's recommendation.

ALS system installation

the install took place in the area of the sound board. The two transmitters were rack mounted in an existing 19” rack. Two 72 Mhz telescoping antennas were placed onto a mounting bracket that was held by the U-bolts. Each antenna was bolted near a cross section of the ceiling pipes.

Two runs of 50 ohm coaxial cable were terminated onsite and connected the antennas to the transmitters. The direct run to the transmitters was approximately 30 ft with slack looped using cable ties.

an interference-free experience at theatre performances show

For ALS systems there are a number of radio frequencies one can choose from. At iProbe, we usually prefer using 72-76 Mhz in the VHF band. Other permissable frequencies for unlicensed users would be the 216 Mhz band.

when using assistive listening systems at locations where a lot of competing radio frequencies may get used, there are chances of RF interference. This can result in a poor experience for the audience using the equipment.

it is therefore particularly important to analyze the environment and to put some thought into which radio frequency channels to choose for the ALS system and where to place the antenna(s).

TECHNICAL NOTE: iProbe is a big fan of the flexibility FM systems (72 Mhz/216 Mhz) offer where the RF environment is right for it. Infrared systems (especially digital IR) are an alternative and if installed properly, offer consistent results regardless of the external environment. Digital IR has a higher price point with advantages in quality and reliability. Line of sight is not an issue when correctly designed as manufacturers provide footprint calculation tools and software such as EASE that help us design IR systems with as many radiators or emitters as needed as high up as needed to make sure the signal is within line of sight as the attendees

iProbe's installer on a ladder placing the first antenna.

The two installed RF antennas for the two FM transmission channels.

George Street Theatre Elevation Transmitters and Antennae Placement above the Sound Board area.

One of the two cases with FM receivers.

Two cases with FM receivers.