I think, anyone can try a ww resistor to reduce the treble. It's easy if you have two sets of binding posts. Just put it across the tweater posts. If not, pull out the tweater and put it across the +/- terminals. 10 watt, but I forget how many ohms.
To the original poster.....
What titles do you have? On CD? On vinyl? Also, how do you know Blue Notes have imaging and a soundstage in any format/issue, be it original vinyl or 24 bit CD's from original tapes?
Here are my recommendations sound-wise for a few.
Larry Young: Mothership (CONN/McMaster)
Jimmy Smith: Prayer Meetin' (RVG) A lower octave of room rumbling bass from the B3 that's absent from the original vinyl, or my tt set-up does not track it. Amazing!!
Andrew Hill: Dance with Death (CONN/McMaster)
Sam Rivers: Fuchia Swing Song (CONN/McMaster) RVG high frequencies without the smear. Very Nice.