Poly Natalia midrange

[saffier]

I need some help on my Poly Natalia (Dick Olshers design)speakers. I upgraded to the new x-over just released by Dick last may. I hav trouble getting the midrange right. Imaging is very nice but the midrange seems to be to upfront, higher piano notes played loud seem to break up. The lower register on the piano is not as solid and full sounding as I would like. I have not changed the amount of the stuffing in the midrange cabinet but have been moving back and foreward the stuffing towards the midrange driver. If I move it forward the sound gets muddy and an 'S' will sound like a 'F'. If I move it to the back the sounds gets to harsh.
Is there to much stuffing in the enclosure? Or should I make the midrange cabinet bigger in volume (I can do that without changing the outer dimensions). Did anyone have had the same problem?
The mid and the tweeter are 5cm seperated from eachother, is this to far, should they be placed closer together?
Oh, I run them with SET 300B amps.
Thanks,
Saffier

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