mrl, the above nht plot is an example of an extremely accurate (ruler flat) frequency response - i have never seen anything like that b4. even the revel b15 plot above is not as flat or impressive as the nht's. u r talking about spl when u say the nht is not comparable to svs pb2+. do u still have the nht u2 sub? i would like to hear your comparsion between the two's when they are critically evaluated for accuracy, musicality and enjoyability, etc.