i think a separate sub (more than an 8in) would be a big improvement. i have never heard anything out of any powered tower that really blew me away. if you did get a separate sub i would dedicate it only for lfe, then i would set any front speaker with a powered sub to large and feed it its bass through the pre-out for that channel which would have to be split (to power amp and to speaker). if you think that 3 8's 150wts each is the best bass you can get, then perhaps you need to audition some good subs. i have used a lot of setups in my hts, and i really prefer the setup mentioned above, although my current setup is slightly different, being that i have seperate subs for every speaker (seeing as they are not powered towers). my settings above could be tinkered with (i.e. large in relation to crossover adjustments may need to be different, meaning if you could crossover really low then you could set the speakers to small still... i dont know what the 950 has..)
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