Infinity Beta speakers

Does anyone have any tips for getting the best out of these speakers, room placement, or mods? I've been using them quite happily for a few years, but the bass always seems a little 'thick' and heavy.
I've had Betas for 7 years. Set up according to the manual with no mods. They are very amplifier sensitive. Suggest Audio Research tube amps for the mid/twt columns and - believe it or not - QSC PLX 3002 for the bass. The QSC can be purchased for less than $1000 new at musical instrument dealers. It beat out Krell, Bryston, etc. by taking bloom out of the bass and adding "punch". 900 W/ch @ 4 ohms.
I agree with Hrcapers on the ARC amps on the panels. I recently found that replacing the non polarized electrolitic capacitors in the crossover found base of the planars with 250 volt polyprylene capacitors of the same value to make a huge improvement in clarity as well as control of the lower frequency of the planars, making them match the woofers better and giving less bass boom. Highly recomended!