It is already break-in?
What is your amp?
EDIT:
once the music gets more complex definition is lost.
As this speaker is not a sweet peach It could be that your amplifier canot handle the demand for too much power with complex music, especially with the combination of low sensitivity 86dB and low impedance 4ohms, maybe 4Ω impedance is just nominal the real impedance may be less, add to it a complex 2.5way xover.
Sensitivity (dB @ 2.83V/1m) 86
Box Principle Bass reflex rear ported
Crossover 2.5-way
