Apparently, the early days of The Wave were not the usual David Sanborn/Sade segues. There was a lot of singer-songwriter and jazz fusion stuff in the playlist. KEZX-98.9 in Seattle had a similar approach, closely related to adult album alternative, and they ironically would become a very popular smooth jazz station (which this poster grew up with regularly in Seattle's northern suburbs). I recall my family had David Sanborn's "Time Again" CD on the rack. My eclectic father was a HUGE Jeff Beck fan (even saw him at the Puyallup Fair...and had me in the stroller, I think I was 2 years old), but didn't mind some of the more "mature" instrumentalists on KWJZ as well. He couldn't stand Kenny G. To this day, the average Joe thinks of smooth jazz as "sleepy elevator music" that Kenny G mastered.
My dad was also a big fan of 88.5 KPLU's Saturday night Blues show. I'm happy to see that John Kessler is still doing the show on Saturday and Sunday night at what is now KNKX. I can still remember the John Lee Hooker, Muddy Waters and Stevie Ray Vaughan CDs...he LOVED all of these artists! (Way off topic)
Before the PPM, KTWV, WQCD, KWJZ, WNUA, KKSF, and other smooth jazz stations were often in the top 5 in Arbitron ratings (sometimes even #1). When the PPM was introduced, the ratings dropped like a rock, and smooth jazz faded quickly from FM airwaves.