Frequency Range - Bookshelf Speakers


For a 2-channel stereo system, which consists of a pair of bookshelf speakers and a powered subwoofer, what difference does it make if the bookshelf speakers go down to 70Hz vs. 30Hz (or anything else in between)?
agiaccio
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Bob is right, again. I personally like subs. You can put the bass anywhere you want for the best integration and let the monitors handle the rest. It will depend on the monitor's drivers and crossover as to the quality of the midrange. Better that way than to try to make a monitor play frequencies below 60 Hz. The sub may be localizable if it plays much above 80 Hz or is too loud. I prefer a monitor that is allowed to play full range and a sub that you can change the crossover, and phase. Its your best chance to integrate it without it being noticed.
Vinyladdict said "If I'm sending everything below 60 or 80hz to ONE sub (essentially mono'ing below 60 or 80hz... probably 80) should I have no problems with "woofer pumping" and subsonics?"

Did eliminating the subwoofer affect/help this problem? Do you still have rumble or subsonics without the sub? Could this be another reason not to use a sub? To eliminate modal response problems and inherent vinyl "noise" (subsonics and rumble).

Bob
much of this depends on room size and musical genre. imo using l/r monitors that on their own can't do a pretty good job on fairly deep bass, say @50 hz is not logical. depending on who you rely on for info, most bass is non directional below @150 hz. a speaker so small that it cannot produce lower harmonics without relying heavily on a sub is gonna sound off without some incredible fine tuning. if you know of a small spkr that plays flat down to 30 hz let us know because unless you have a BIG listening room or crank pipe organ and tuba you have eliminated the need for most subwoofers. i love my sub but just set it at low x-over...monitors with no decent bass just do not cut it in the realism dept with me.