On Feb 6, 9:36*am, "Serge Auckland"
wrote:
"David Looser" wrote in message

...

"Karl Uppiano" wrote in message
...

Fortunately, long wavelengths and large excursions are mostly in the low
frequencies, which tend to have minimal out of phase characteristics
(which is why subwoofers are practical).

More to the point as far as subwoofers are concerned, the ability of human
hearing to determine the direction of a sound source becomes less
effective as the wavelength lengthen, becoming pretty well non-existent at
frequencies of 50Hz and below. So not only does it not matter if these
frequencies are presented in mono, but it doesn't matter much where the
subwoofer is in relation to the subs either.

David.

That has not been my experience. I ended up with two subs, each sitting
alongside each main, as I couldn't get on with one only. If the sub was
centred between the two loudspeakers, that wasn't too bad, as at least the
extreme bass was mono, but when the sub was to one side, it was most
peculiar.

That's primarily because most subwoofers aren't: they tend to have
substantial output at higher frequencies anyway. The very low
frequency material could well be in mono, but stuff an octave or
two higher could have substantial difference information, and
that can easily find its way through many subwoofers.

wrote in message
...
That's primarily because most subwoofers aren't: they tend to have
substantial output at higher frequencies anyway. The very low
frequency material could well be in mono, but stuff an octave or
two higher could have substantial difference information, and
that can easily find its way through many subwoofers.

So true, I find it annoying that what we once called simply a woofer, is now
called a "sub woofer" by many manufacturers. Many don't go anywhere near
20Hz, and may go well over 200Hz by design. And many more go there simply
because of inadequate filtering.

MrT.