Dave Specter didn’t pick up a guitar till his late teens, yet in his 20s he was Son Seals’ rhythm guitarist for two years, and soon he was a bandleader himself. Specter grew up amid Chicago’s blues scene and became one of its great players and ambassadors. Here he recalls the glory days of Chicago’s blues clubs and the varying vibes. He recounts the evolution of his sound and his progression of guitars. He explains how he creates a solo and why, after years of playing mostly instrumentals with the occasional guest vocalist, he began singing. He tells how his recently released “The Times They Are Deranging (The Buck Stops Where?)” fits in with the songs of conscience he always has admired. And he offers the origin story of Space, the excellent, musician-friendly Evanston, Ill. club where he’s a partner. (Photo by Mike Hoffman)