Maybe, maybe not. As Hambone aptly pointed out, the best way to compare is when the bass is played unplugged. However I'm not aware of anyone who's ever gigged or recorded with an unplugged electric bass! Check above, I never said wood can't make a difference! My point is that there's enough tonal variation within one particular species to overlap the tonal variations in other species. F'r instance, you can't say "alder is red and ash is blue". Alder and ash could both be purple. And I'm talking about solidbody Fender-style basses here. When you get to multi-lam multi-species hippie sandwiches, all bets are off... see below!