I recently restored a pair of the classic Acoustic Research AR3a speakers, circa 1970.  The deep bass is still very impressive, but by modern standards, the crossover is pretty primitive, and that, together with the ad hoc driver placement resulted in severe cancellation modes in the mid-highs.  The woofer also had a big hump at the top of its range, which colored the sound.  Still, it sounds better than you might think.

Here are the measurements: