i have the plv-7 and it doesn't hit below 30hz very well. according to the manual, it's not supposed to hit below 30hz. not sure how well the stealthbox will hit. 2 songs i tested with are "heat it up" by bubba sparks and "hood figga" by gorilla zoe. the plv-7 doesn't hit the low rumble very well on either song. but you're not going to listen to that many songs that will go below 30hz and the plv-7 hits pretty hard on almost every song.