Hill United Presbyterian Church has discovered some interesting keys to worship. The keys will be featured on Sunday as eleven sets of nimble fingers assemble in one room to play four acoustic pianos, one organ and six electronic keyboards as part of a special service.

The third annual piano service will be offered at 10:30 a.m. in the church's sanctuary.

"We had the pianos, so we decided to use them," said the Rev. John Porter, the church's associate pastor, whose mother Carolyn Porter traveled from Massillon, Ohio, to take part in the service.

Carolyn Porter will play one of three upright pianos normally spread between the sanctuary, choir room and a lesson studio in the basement. A grand piano is also kept in the sanctuary.

The six electronic pianos were moved to the church temporarily for the service.

Although the service was first introduced three years ago, it has begun to evolve with each performance. "We're not used to this many pianos," said Peggy McGuirk, the church organist who initiated the annual tradition. "Before, the most pianos we've ever use were five."

McGuirk also said this will be the first year youths will be featured among the musicians.

Tommy Walters, 16, of Center Township, is one of four teens who will play this year.

"It's amazing," said Walters, who has attended previous services as a spectator. "The difference between the sound of one piano and the five that were there: it's just a huge beautiful sound that filled the room.

"I've been in bands and concerts, but this is just a different feel - a whole different world."

Although many of the musicians are members of the church, a few like Walters are associated with the group in different ways.

Walters takes piano lessons from Kathy Sawyer, the pastor's wife, who will also play on Sunday.

Bob McGinnis of Chicora is a former music director of the church who has participated in the previous services."It's hard to get this many people together," McGinnis said laughing. Wednesday's rehearsal was the first of two due to take place before the service."It's an opportunity to perform. … You meet old friends and you meet new people," he added."It's nice to add the young people this year because we have so many young piano players coming up," McGuirk said of the talent available in the community.McGuirk said she got the idea from a friend in Ohio, whose church rents pianos for a similar annual service. With the instruments and talent available, McGuirk said it seemed like a good service to offer at Hill in late summer, before the choir returns from its regular summer break.Adult pianists will include McGinnis of Chicora; Carolyn Porter of Ohio; Kathy Sawyer of Butler; Claudette Sanzotti of Center Township; Jessica Sanzotti of Butler; and John Thomas of Connoquenessing Township.Youth pianists will include Walters, as well as Emily Broad, 14, of Center Township; Lauren McElhaney, 12, of Center Township; and Nathan Moses, 14, of Butler Township.McGuirk will play the organ.The musicians will play hymns "Praise Ye the Lord, the Almighty," "His Eye is on the Sparrow," "The Church's One Foundation," "Thou Art Worthy Medley" and "Rejoice, Ye Pure in Heart."