Concentric drivers

“Doppler (intermodulation) distortion would show up as a reduction in clarity at high SPLs, particularly with bass-heavy, complex music.”

@Duke—do you have any experience with this?

@islandmandan 

I think that happens a lot in this hobby. Too many folks looking for the next big thing or coming up with some phantom malady. 

@audiokinesis Said!

Doppler (intermodulation) distortion would show up as a reduction in clarity at high SPLs, particularly with bass-heavy, complex music.

Duke

I agree that’s why my main JBL 2 way speakers have two15’’ woofers.

Mike

I would think a 3 way design would solve the concern?

Who cares?  Listen to the speakers with your music at different volume levels, and if you still like sound what difference does it make if there’s a Doppler effect or not? There are ALWAYS trade offs between different speaker designs, which is why your ears need to be the final arbiter.  I’ll also add that I think concentric drivers are time/phase coherent (or maybe one or the other) that may outweigh any Doppler effect.  Let your ears be your guide.  Personally, I think there are much more important speaker issues (cabinet, crossover design/parts, driver quality, etc.) than worrying about the Doppler effect.  Just my $0.02 FWIW.