For a long time, one of the constants in the Sonoma County music scene has been Blair Hardman, jamming on bass in jazz groups all over the area, operating his Zone Recording studio in Cotati, lending his voice to radio shows and commercials.

As he says, “It’s been a long time since I came into The Press Democrat with info on my first band in 1971. That was ‘Hot Chakra.'”

Now, he has come to pressdemocrat.com to say he’s throwing himself a birthday party, although he doesn’t mention exactly what birthday it is.

“My annual Jazz Party and Birthday Bash is coming up,” he says. “This group started 25 years ago and played every week in Sonoma County for about 15 years.”

The lineup for this band should impress any locals who know their Sonoma County musicians: Rita Thies, sax; Tim Haggerty,  keyboards; Randy Quan, guitar; Jeff Forehan, drums; Blair Hardman, bass.

The show also features Frank Hayhurst & the Zone All-Stars and Uncle Wiggly.

His “Blair Hardman Jazz Party & Pisces Birthday Bash” starts at 9 p.m. Saturday, Feb. 20, at the Tradewinds Bar In downtown Cotati. Admission: $8. Information: (707) 664-1221, www.blairhardman.com.