bright up "warm sound" speakers

Hi,
My system is too warm for my listening taste. The low to mid bass seemed to be muddle, and the high are not as detailed as I would like to hear. I would like suggestions on how to "brighten" it up a little and not breaking the bank. I mostly listem to acoustics music, opera, classical, blues,very little POP and some Jazz.
Here is my system:
Sonatina II
Musical Fidelity A3CR Amp
Proceed Pre preamp
Jolida CD100 (stock tubes)
Audioquest Midnight speakers cables
Audioquest Lapis interconnect
BL1 interconnects
Listening room is 14 X 18 ft

Someone had suggested to replace speaker cables. What do you all think? If you think what I have right now is the best it can sound, then I can live with it. But if there are improvements (not breaking the bank) to be made, then please fire away. Thanks in advance for your suggestions.