Regular theater-goers may be familiar with the experience of straining to see from less-than-optimum seats. Or with the annoying sound of nearby patrons crinkling candy wrappers or whispering too loudly.

But those irritations pale in comparison with the limitations faced by lovers of the performing arts who have visual or hearing impairments.

Two new assistive technologies that help those patrons more fully enjoy the theater experience will be showcased here in the coming week.

One, called live audio description, will be available during City Theatre's matinee of "Fiction" at 2 p.m. Sunday.

Patrons who are blind or have low vision are given headsets and small receivers. A trained describer, speaking into a microphone, relates actions happening onstage, giving details about sets, costumes, lighting, and other theatrical elements not obvious from the dialogue.

"It's really the first live theater that's being audio-described in the Western Pennsylvania region," said Diane L. Nutting, City Theatre's director of education.

Another aid is a "sensory forum" at 1 p.m. that allows low vision patrons to tour the stage for an overview to create a kind of "tactile map of it in their mind."

This is kind of a test-run for the technology, and Nutting said that feedback during a post-show symposium will give City Theatre direction on how to improve live audio description next season, when it will be offered for all productions.

"The next step of the project over the summer will be a training program for audio describers," she said. The goal is to train between 12 and 20.

In addition, City Theatre expects to work with other cultural organizations locally to serve as a kind of clearinghouse for the acquisition of the technology.

The project is funded by a $25,000 Verizon Foundation grant funneled through VSA Arts of Pennsylvania. VSA Arts is an international organization that promotes equal opportunities in the arts for people with disabilities.

There is no charge for live audio description, Nutting said, but patrons are requested to call ahead to reserve it at 412-431-2489. Choose the option that lets you speak to a box office representative.

At Heinz Hall on Tuesday, some patrons with hearing impairments will be able to take advantage of a system called I-Caption during the production of "Big River," a musical that is sung, spoken and signed.

It features a hand-held unit about the size of an index card that displays the text of the entire show verbatim, including lyrics and dialogue. The text is automated and synchronized with sound and lighting cues. A polarized screen keeps nearby patrons from being distracted by light or moving text.

"Some people don't know sign language, so it adds another layer of accessibility," said Jennifer Graves, of the tour's management.

There is no charge for use of the device, but there are only 10 units with the tour, so they'll be available on a first-come, first-served basis, she said.

I-Caption was developed by the Sound Associates Inc., of New York, which won a Tony Award in 1980 for introducing the Infrared Listening System to Broadway theaters.

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