Even if done properly, biamping the Klipschorn is not a good way to get more or punchier bass. Increasing the level of the bass bin will increase all frequencies below 400Hz (or wherever you set the low band of an active crossover, but going lower with the stock mid-range driver will be problematic and that's a whole other story).
The frequencies between 300-400Hz are some of the ugliest frequencies around if they are accentuated. This is not the way to go to remedy what you are describing.
Part of the problem may be placement, which has already been pointed out. But even when they are set up adequately, the lack of distortion with good horn loaded bass is very different from smaller direct radiators. The inherent distortion found with relatively small direct radiating woofers is subjectively punchier.
Get the things set up correctly and get used the sound. It won't take long and what effort you expend will be well worth it.