Jake Vistoso and his brother, Evan, both wear hearing aids, yet had trouble understanding the rabbi at their synagogue in Newtown.

Since Jake had just turned 13, he wanted to tackle that auditory challenge for his bar mitzvah project.

The answer was a "hearing loop" — a strand of wire hidden under the carpet of the sanctuary at Congregation Brothers of Israel.

Jake helped raise more than $3,000 for the loop system, which transmits audio from the rabbi's microphone directly into most hearing aids. No headset required.

A miniature version of this technology has been around for decades, required by law to be built into all land-line telephones. If a hearing-aid wearer has trouble hearing a phone conversation, he or she simply pushes a button or switch on the hearing aid, activating an internal "telecoil" that receives a wireless transmission of the telephone's electromagnetic signal.

Larger loop systems, which transmit sound to telecoil-equipped hearing aids in a room-size setting, have been common in Europe for years but only recently have started to gain a foothold here.

"It's made a tremendous, tremendous difference," said Steve Minsky, 69, another member of the synagogue in Bucks County. "I was actually hearing things that my wife was not hearing."

In addition to the synagogue, which installed its loop in November, a variety of local venues have these systems in place, according to the Pennsylvania office of the Hearing Loss Association of America. Among them are the Town and Country Players theater in Buckingham and the Free Library of Philadelphia, which installed one this year in its Montgomery Auditorium, where visiting authors speak.

And in New York City, nearly 500 subway station ticket booths and more than 700 taxis have the loops, enabling the hearing-impaired to communicate with people on the other side of a thick plate of glass.

Such loops are connected to an existing sound system, or in the case of taxis, to a microphone embedded in the partition between driver and passenger. An amplifier pushes the audio through the loop of wire, generating an electromagnetic signal that can be captured by any hearing aid with a telecoil.

All it takes is a push of a button or switch to activate the telecoil. These coils are included in most hearing aids and in all cochlear implants.

When the button is pushed, it also shuts off the hearing aid's microphones, so that the wearer receives only the sound transmitted from the loop and no ambient background noise.

As Jake Vistoso and his mother, Jennifer, looked into ways to improve the sound during synagogue services, he thought of the system he uses at school, which transmits the teacher's voice to an FM receiver on his hearing aid.

But many hearing aids do not have FM receivers.

Then the Vistosos, who live in Hamilton, N.J., heard about the loop technology at a synagogue in Lawrenceville, N.J., and forged ahead.

Jake's mother suggested that he wash cars to raise the money.

"Mom, that's a lot of cars," Jake responded.

Then mother and son thought of New Jersey Walk4Hearing, a Hearing Loss Association of America fund-raiser in which the family participates each year.

For the event in October, organizers agreed to let the Vistosos and more than 30 teammates use a portion of funds raised toward the loop system. They called themselves "Hear, O Israel" (pun intended).

Jake earned more money by walking dogs and doing yard work. Synagogue members also donated.

"Jake energized the team," said Joan Hersch, principal of the synagogue's religious school. "Jake made it possible."

The $3,500 system was made by Michigan-based Contacta Inc. and installed by East Coast Hearing Loops, of Jamison, Bucks County, which also put in the system at the Town and Country theater. Chip Hilger, the company president, has a personal connection to the issue, as he wears hearing aids in both ears.

A competent installer is key; otherwise users may experience dead spots and other flaws, said Janice S. Lintz, a New York hearing technology consultant.

Lintz, whose daughter has a hearing loss, spent years as an unpaid advocate for hearing loops and was instrumental in getting them in New York taxis. Now she advises businesses, museums, and other venues that seek to install the technology.

In this region, most theaters and other venues offer other assistive-hearing systems that require the wearing of a headset. Independence Visitor Center, at Sixth and Market Streets, has a hybrid approach.

In the center's theaters, the hearing-aid wearer has to wear a loop of wire around the neck, and must first ask for it at the front desk. During a recent visit, the system was spotty, transmitting the actors' voices in a short film about the colonies' struggle for independence, but not the narrator's voice. (The theaters also display captions beneath the screen.)

Not good, says Lintz. Even if the portable loops work, users do not want to wear an additional device, much less have to wait in line to get it. Much better to enable access through a simple push of a hearing aid button.

"This is a business decision," Lintz said. "You provide good access, and you enhance and access an untapped market."