Perhaps whats missing in most of the speakers that are discussed here...a very large stand mount, but 90 lbs.....astonishing bass, so you do not need a sub. Frankly guessing the proper cutoff on the sub in most systems is the weak point. In most cases you are duplicating bass notes and never do figure out why your system doesnt sound right....these are clean and tight with no droning muddy bass......If Paul Klipsch was young today, this is what he would be working on....see the specs on the IB2is....... http://www.pmc-speakers.us/