Rant oncoming.
Blu, it's curious that some owners of nearly full-range speakers and an excellent sub(such as the EP800)are hesitant to set the speakers at say, 80Hz rather than 40Hz. They're concerned about "wasting" a very small part of the speaker frequency range, while not expressing a similar concern about not using as much as half of the sub's range to its best effect.
John, this makes the assumption that the sub is 'better' about playing the same range as the floor standing when the full range speakers also play, perfectly fine, down to say 40Hz or 50Hz (or lower depending on the speaker).
The blanket statement you put forth (sub better in this range compared to a full range speaker) is purely subjective.
Both those speakers (a full range or a sub) can play equally well within their frequency limits. There is no reason to believe otherwise.
Again if the goal is to have a completely linear frequency reproduction, then the only way one can qualify which is better would be by reviewing a frequency response graph.
Not all people own subwoofers with DSP controls to flatten the response so we cannot assume all own an Axiom sub with this ability.
As long as the sub isn't localized, setting the crossover to a higher number is the way to go, making maximum use of the frequencies it does best both because of inherent design together with the ability to locate it specifically for best reproduction of those frequencies.
Again there are no definitive numbers on this.
Review a frequency response curve for a M60 between 50Hz and 150Hz and try to explain how that is 'worse' than the same range played by a EP350.
Also missing from this comparison is the apples to oranges technical differences between a full range speaker and subwoofer for which the sound of the full range speaker might produce bass (even low bass) better than a sub.
Does someone have a monster full range speaker with 12" bass drivers but only a single EP350 sub?
Because they do exist out there (i have one close; the Tannoy Definition D700 uses a 10" driver and ranges well down to 35-40Hz).
Noting from my another example of technical differences, the M80s use two 6.5" drivers which has a greater surface area compared to the EP350 which uses a single 12" driver.
From that spec, the M80
technically has the ability to move more air for low range sound (and hence its quite low frequency response measuring -3dB at 31Hz). Obviously the limitations come in for amp power and box size which is where the sub now becomes 'better' but only for the very low range.
I've been running my M60s at full range for years, using a crossover point of about 45-50Hz with an EP350 sub.
The bass sound integrates well and i've tested moving that xover point up and down to where the bass sounds thin (a hole in the frequency response b/w the M60 low end and the subwoofer tail off), or where the bass sounds fat (a doubling up of bass with the M60 low end and overlapping the EP350 as the xover is clearly set too high).
Why do i not use the EP350 for higher bass frequencies?
Because i find the sound to be too heavy and bloated especially for music. If i turn down the sub gain, then explosions in movies sound too weak.
Room effect?
Sure, there likely is. But i can't move the sub into the middle of the room either just to get rid of a standing wave or any other numerous issues that may arise by leaving it in the only location i can; next to the M60 on the left.
Having been around the forums for years and soap boxing against many different opinions of audio, though primarily the snake oil nonsense, i'm surprised this one (subs are better at 40Hz to 150Hz; set your large speakers to small for a xover) continues to be perpetuated as the "preferred" and "technically superior" option (discussions of official Dolby theatre technical suggestions aside).
It isn't very scientific of your normally balanced perspectives John.
