I feed a RT 1000p tower with 405 wpc Carver Grand Cinema amp (upper posts) and it has a built in amp rated at 70 watts (sub, lower posts). The binding posts are strapped with the tower amp plugged in. The audio signal comes in and goes to both sets of posts. The sub is being feed the 405 wpc and going thru the amp. Is the tower amp amplifing the audio with 405 watts audio? Or is the tower amp not having any effect on the 405 wpc audio thru the subwoofer? I have the gain on that tower amp at halfway (12 o'clock on the gain).