"There's nothing like it," avows Stuart Dempster, who after several decades still cherishes the singular acoustic space lurking under Fort Worden State Park just a few blocks north of Port Townsend.

Known among a handful of musicians, "the cistern" is a giant underground concrete drum. Designed to store millions of gallons of water for the now-defunct fort, the empty cistern's round walls and thick square pillars make sound bounce and ring with one of the world's longest natural reverberation times: Take a single footstep, stop, and listen. You'll hear microscopically compacted echoes of that lone step for the next 30 to 50 seconds. The cistern is one of the sonic wonders of the world.

Dempster, a Seattle composer, improviser, trombonist, and all-around artistic treasure, has an affinity for unusual sounds and spaces. A seminal presence in adventurous music since the 1960s—in 1968, he organized the first recording session of Terry Riley's epochal minimalist work, In C—Dempster knows the cistern well.

"You have to learn to play it like an instrument," Dempster tells me, chatting by phone from upstate New York. He's there, with longtime collaborator Pauline Oliveros and other new music avatars, to attend a festival commemorating New Albion, the label that released his classic 1987 album, In the Great Abbey of Clement VI, a meditative exploration of reverberant space.

"The cistern," he adds, "doesn't do much, frankly, but what it does—reverberate—it does so elegantly." Dempster learned of the cistern's wondrous acoustic properties from David Mahler, a longtime Seattle composer who recently moved to Pittsburgh. Back in the 1980s, arts advocate Dan Harpole fought to open the cistern to musicians. Since then, other composers and improvisers such as Jarrad Powell and the much-missed trio Doublends Vert have recorded inside the cistern, which was formally christened the Dan Harpole Cistern in 2007.

I can attest that being inside the cistern is a transformative experience for a musician. Inside, the air is stuffy and humid, like vaporous cotton. Oxygen gets used up quickly, so an attendant waits above ground, near a rusty, rickety ladder. Every breath, each footstep, and even the slightest movement is amplified and elongated, surrounding you with a shimmering sonic dust. After the cistern, I listened to the world in a new way.

For this hour-long performance, Dempster teams up with cellist Walter Gray, percussionist Matt Kocmieroski, and Seattle Symphony bassoonist Seth Krimsky. Together, they venture into the cistern to pipe John Cage's 1962 work Atlas Eclipticalis via speakers up to the surface for us to listen. Don't miss it. recommended

Stuart Dempster and friends perform Fri Aug 22, Dan Harpole Cistern at the upper hill of Fort Worden State Park, Port Townsend, 360-385-3102, 8:30 pm, free.

Classical and Avant-Garde Calendar

Thurs 8/21

COUNT BASIE ORCHESTRA

Here's Exhibit A for jazz becoming a classical music: The eminent Count passed in 1984, yet his band, a few of whom played under the man himself, soldiers on. Through Sun Aug 24. Jazz Alley, 2033 Sixth Ave, 441-9729, sets at 7:30 and 9:30 pm, $32.50.

GOAT

This trio's new disc Special Agent (Present Sounds) opens with a marvelous deception. Drummer Denali Williams sets up a superficially rockish beat that plods for several measures until Greg Sinibaldi, wielding a breath-controlled synth, unleashes a surprising, scabrous lead line that conjoins today's digital glitches with the arcing, portamento textures of early 1970s jazz-rock. Chick Corea and Mike Ratledge would be proud. Part of Jazz: The Second Century series, organized by Earshot Jazz. Fourth floor Chapel Performance Space, Good Shepherd Center, 4649 Sunnyside Ave N, 547-6763, 7:30 pm, $10.

Fri 8/22

MARK HILLIARD WILSON

A plotter of meticulously planned programs, guitarist Wilson proffers a recital in the cathedral chapel that ranges from Josquin Des Prez to the vihuela music of Alonso Mudarra to "the sting of the Gypsy lament" in the works of Francisco Tarrega. St. James Cathedral, 804 Ninth Ave, 382-4874, 7:45 pm, $15, students and seniors pay as able.

DEE DANIELS

Last year when I quizzed this jazz singer about her approach to singing, she remarked that anyone can sing lyrics, but the role of the singer is "to remember that a song is really a conversation." Blessed with a four-octave range, Daniels's elegant phrasing and daredevil vocal pyrotechnics will knock you out. The Triple Door, 216 Union St, 838-4333, 8 pm, $22 adv/$25 DOS.

CARL STONE

A creator of crazily beautiful electroacoustic collages, Stone makes his first Seattle appearance in almost two decades. Essential. Fourth floor Chapel Performance Space, Good Shepherd Center, 4649 Sunnyside Ave N, 789-1939, 8 pm, $5–$15 sliding scale donation.

Sat 8/23

ARTS IN NATURE FESTIVAL

Nestled in the woods and bushes at Camp Long, this two-day event features a lineup that justifies the well-worn adjective "eclectic": Voices of the Animate Air, a multichannel installation by Robb Kunz, trombonist Mark Smason, the Beaver Deceivers (an "Amish-flavored jug band"), the amazing corporeal improviser Christian Swenson, and chamber improv group Guardian Ear. Converted into a "Museum of Sound," the camp's cabins house installations by Dean Moore, Kristin Tollefson, Hollow Earth Radio, and others. Also Sun Aug 24 from 11 am–6 pm. Visit www.naturec.org for a full schedule and directions. Camp Long, 5200 35th Ave SW, 11 am–8:30 pm, $5 suggested donation.

UNUSED LEXICAL VARIABLE

With two acoustic guitars and double bass, this unusually configured trio erupts with frenetic strumming and, best of all, tiny constellations of quietly plucked, spectrally tingling sonic morsels. Gallery 1412, 1412 18th Ave, 322-1533, 8 pm, free, but donations accepted.

Mon 8/25

STRIKETHROUGH

Performance group Implied Violence brings their dateless oblivion and divine repose to this monthly series curated by Seattle School. Strikethrough's ostensible refusal to admit attendees pries open a crepuscular space for you to surmise what might be happening, what should happen, and what will never happen. You can probably get in, but when I went a few months ago, I simply sat at the bar and imagined. Rendezvous, 2318 Second Ave, 441-5823, 8 pm, free (probably).