It's on video where Mr. Sadowsky (at the 2014 Bass Player Live bass set up clinic), said that he notices more tonal difference from the fretboard wood than body wood.
Mr. Tobias had a slightly different opinion when he answered the question.
I don't have an answer. However, I can say that I owned an extremely heavy ash body MIM Fender FSR jazz bass with a rosewood fretboard that had a serious slap tone.
The bass was passive, but the slap tone sounded like the bass had a preamp! I believe the body wood was HEAVY Northern Ash, and the reason why it had such an incredible slap tone.
P.S. - I guesstimate that the bass weighed 10 + lbs.