what spkrs work with an 8008st???

looking for advice anyone can offer on a good speaker in the $2000-$4000 range that matches well with the aragon 8008st.

just purchased this amp and running a pair of rogers p-22s with an audio research sp-9 mk3.

it may be my room more than anything which at the moment lacks a sofa and many other sound absorbing objects.

problem is when the volume gets a little high, mid range gets muddled and unclear.

any suggestions on a good match with the 8008st would be greatly appreciated.

thanks

jp