So the last thing one would expect when Charles Gayle answers his phone is a soft-spoken, affable sort who seems almost embarrassed by an interview request, shrugging, "What have I got to say?"

Then again, Gayle seems to be in less of a preaching mood these days. The 1990s saw a run of releases with titles like Kingdom Come, Consecration and Delivered, full of fire and brimstone soloing that cried to the heavens. But closer to the end of the decade, Gayle started experimenting with his first love, the piano. A few cuts would crop up on CDs, sounding generally like a more linear-thinking Cecil Taylor. As his playing progressed, Gayle's piano concepts diverged from his sax playing to greater degrees.

IN THE ZONE: Unlike his straining, searching sax, Gayle's piano is contemplative and nostalgic.

The just-released Time Zones (Tompkins Square) is Gayle's second solo piano CD, his first to consist entirely of original material. As opposed to his straining, searching sax, Gayle's approach to the piano is contemplative and nostalgic; more than one reviewer has noted the way he seems to revisit the entire history of jazz piano on each track. The effect is like peering into Gayle's subconscious as one idea begets another, concepts and melodies rising from the torrent only to submerge again, fresh inspiration sparking a memory that fades as soon as it appears. A stride piano line suddenly ends with a Monkish flourish; a jagged Taylor assault abruptly smoothes out into an Art Tatum run.

It's unusual enough when a musician can become adept at two completely different instruments; put Time Zones to the blindfold test and no one would guess that this isn't a lifetime pianist. Stranger still that Gayle's voices on the two instruments are so diametrically opposed. According to Gayle, that difference was wholly intentional. "I didn't want to get into playing the same style of music on piano that I was playing on saxophone. For two reasons: One is, well, what's the point? And the other one is, I just like that kind of music. I'm not really trying to copy anybody, but of course I've been around all of that music since I was a kid. Whether it's stride or fast or blues, it's just in me. I didn't want to run away from it just to do something completely original."

Then again, Gayle simply enjoys a challenge. Bored with his usual axe, the tenor, he has been playing alto increasingly in recent years. "I like the fact that I have to think differently because it makes me work harder," he explains, regarding his interest in both new instruments. "It would be nice just to walk out on stage one day and just shatter everybody's mind. I don't mean to impress people, but just to break through everything. And the problem with that is, free music has already been invented, and the music with chords and symbols, that's been invented. Atonal's been there. So you don't have anything left. I'm trying to find something else. I don't know if it's there, and that's the big challenge. I won't rest till I find it."

Gayle draws a distinction between the traditional notion of "free playing" and actually being free. He explains, "It's very difficult to be completely free. No ... it's easy to be completely free, but the ego doesn't allow it. If you listen to even the freest players, you hear a style. So that means they're not free. They might have been free at one point, but then they gave up freedom for style so that people could recognize their music."

That restlessness is a key element in both Gayle's music and his life. The one characteristic that his sax and piano playing do have in common, and that is also clear in speaking with him, is that he is constantly sifting through a barrage of ideas. "Sometimes it gets a little busy up there, and sometimes the horse don't have reins on it," he laughs. But already, new sounds and new concepts are emerging. He muses that he's thinking about changing his style on piano.

"It's not bad to be content. It's not the worst thing in the world. But I'm never content. Not even close. Even after I get off the stage I want to change everything. I know it's a curse but it's a blessing. I don't have anything else except to escape who I am right now."

Charles Gayle, solo piano, Thu., July 13, 8:30 p.m., $12, Ortlieb's Jazzhaus, 847 N. Third St., 215-922-1035, www.arsnovaworkshop.com.