PAM Bricker and Debra Tidwell, two Washington vocalists who consistently succeed in transforming words, melody and rhythm into emotional experiences shared with an audience, are currently in extended engagements here. Bricker sings Fridays and Saturdays in the Riverfront Piano Bar of Charlie's and Tidwell appears at Marley's in the Henley Park Hotel Mondays through Saturdays.

"It has to be not only nice sounding, it has to mean something," says Tidwell of what she looks for in a song. "More specifically, it has to either mean something to me personally or be something I can make meaningful to someone else. A lot of things that I sing are not my personal experiences but things that I can show some empathy with."

A cabaret singer, Tidwell has performed revues of Kurt Weill, Stephen Sondheim and Ira Gershwin music and appeared in dinner theater productions in the lead role of "Hello, Dolly" and as Bloody Mary in "South Pacific." Her earliest memories of singing are the Latin masses she learned with her church choir. In high school (Notre Dame Academy) she joined the glee club and sang with a rhythm and blues group. As a communications major at De Paul University in Chicago, Tidwell tried her hand at singing radio commercials (instant breakfast food and sausage) and joined the college jazz band as vocalist. She traces her influences back to the Duke Ellington, Count Basie and Benny Goodman her grandfather listened to on radio and to the Motown sound she grew up with in the '60s. "The Supremes and Dionne Warwick--the first singer I ever learned every song of--and I kind of graduated to Aretha Franklin, Gladys Knight and the Pips and Barbra Streisand," she says.

"It's always wonderful when I walk out and see that these people have come down to share some time with me," Tidwell says of the audiences that have turned up for her one-woman shows. "I think the best feeling in doing the one-woman shows is being able to get on stage and just totally allow myself to be myself. In fact, it's one of the reasons why I do one-woman shows. It's because of the strength that I feel when I'm out there performing mostly in being myself."

Bricker, who sings a repertoire of older standards at Charlie's, says she is often asked, "How do you know these songs and why does your voice sound so mature when you look so young?" She answers that she looks younger than she is and that she has long been a fan of the great songwriters--for example, Ellington, Gershwin, Cole Porter, Fats Waller and others. "The structure of even the simplest tune is logical and yet sophisticated, some of them very sophisticated musically. There's no getting around it, the tunes are well-written.

"I am somewhat picky about the lyrics I sing," admits Bricker. "I tend to stay away from really bitter songs about relationships that have gone wrong. I tend to choose happier lyrics and I feel that a lot of what is expressed in those songs is universal--it doesn't really go out of style when you're in love with someone. And I pretty much believe in true love."

Piano lessons at age 4 launched Bricker on a musical odyssey of a quarter century: the European keyboard classics, first-chair clarinet in high school, madrigal singing at summer music camp, self-taught folk guitar , instant recognition in the Boston area in the mid-'70s with several rock groups, including one under her own name, work in Washington-area jazz clubs for the two years since she settled here and a recent tour of Spain with the Washington Jazz Battalion.

The daughter of a psychologist--and a child of the '60s--Bricker was introduced to B.F. Skinner's Walden Two when she was 12 and left Hampshire College after one semester to live in a rural Virginia commune. "I lived there for two and a half years until I was just sort of overwhelmed by the desire to become a musician," she recalls.

"I still maintain my '60s idealism in a lot of areas, so to sing some of the songs means I'm glossing over certain little disagreements I might have. So I'll treat it as a theatrical piece--I play the role that is portrayed in the song and just become the character and it's not necessarily me singing, 'Oh, you done broke my heart.' "