If you run the sub "hotter" than the auto-calibration set it, either by increasing the volume control on the sub or the sub trim control, the other trim levels aren't affected. While some prefer to set the sub a few dBs "hot", the 8-10dB you mention seems a bit high. Keep in mind that a sub isn't supposed to call attention to itself as a separate sonic entity; the impression should be that the sub isn't working but the speakers are putting out more bass.

-----------------------------------

Enjoy the music, not the equipment.