From what I read all over the net, subs (preferably 2 or more) are pretty well essential for proper HT sound reproduction. I agree.

Most speakers, unless stratospherically priced, cannot equal the output & low freqs of a decent powered sub or two.

Furthermore, the sub(s) take the load off the amp/receiver as the LFE is handled by the subs' amps thus allowing only the mids & highs to be driven by the amp/receiver.

For me, bookshelves, each with its own sub, is the most cost effective approach. Others prefer towers & sub(s)...

TAM