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Ed Presson[_2_] Ed Presson[_2_] is offline
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Default Ways to make speakers go anywhere.

Peter,

Thanks for the post on the AR recommendations. Somehow, I never saw their
results this complete, although I'm old enough.

Do you have any ideas about how these recommendations apply to dipole
speakers?

Ed Presson

"Peter Wieck" wrote in message ...

On Thursday, May 9, 2019 at 6:21:40 PM UTC-4, Howard Stone wrote:
The speakers I have are really annoying because, to get them sounding as
good as they should, they need to be positioned in places I don't want
them to be. 1m from walls etc.

I want my speakers low down and unobtrusive, or high up on bookshelves. I
want them hiding away in corners and right up against walls. And I want
speakers which are flexible, which can be moved anywhere.


As it happens, and apart from (very) exceptional room acoustics, your
dilemma was addressed quite specifically by no less than Acoustic Research
and Edgar Villchur back in the dim and distant 1960s. And, much of the ARs
designs historically were based on solving placement issues.

All of the above based on minimum 8"/200 mm woofers and against the wall in
"conventional" box-type front-firing speakers. Smaller woofers are hopeless
in delivering clean bass unless in many multiples - which brings on more
problems than it solves.

As follows:

Starting on the LONG wall of the listening room:

a) Place speaker A at the 1/4 point from one corner. Makes no difference
which. The woofer should be at least one (1) woofer diameter off the floor -
making the center-line at 1.5 diameters. The tweets should be IN or UP.
b) Place speaker B at the 1/3 point from the opposite corner.
c) While playing a full-range, well-recorded, familiar signal at
normal/slightly lower volume, tweak Speaker B to achieve the best
sound-stage. 95% of the time, B will move closer to A. Starting out, your
sound-stage will be ~2/3 as wide as the distance between the speakers and
about as deep as half the distance between them.
d) Once you have achieved a comfortable sound-stage, tweak either/both
speaker heights to achieve the best possible signal balance. If you have
wide-dispersion (as in dome) tweets (and, ideally mid-ranges) *YOUR* ear
level will not be critical.

And, this should do it - excepting very strange rooms or strangely shaped
rooms.

Notes:

1. At no time should the speakers be symmetrical on a given wall _UNLESS_
there is something between them (such as a fireplace) that renders their
relationship asymmetrical within the room. Symmetrical placement invites
standing waves, cancellation waves and other forms of interference. For the
same reason, no speaker should be placed at a mind-point between two walls.
2. Exactly the same exercise obtains on the short wall, except that bass
will be enhanced, sometimes too much.
3. Exactly the same exercise obtains from the ceiling rather than the
floor - but the speakers should be bass-up if vertical in that exercise. No
change if on their sides - tweets in.
4. With good speakers (clean response curve) final placement will very much
depend on the listener and his/her preferences. And, therefore why the
exercise should be with all settings "FLAT" and with familiar and full-range
signal. Changes from a good start will not require changes in speaker
location(s).
5 And to repeat: NOT SYMMETRICAL!

Once you have found a configuration that pleases you - give it a week. Mark
the locations in some way, then start over but with a different signal. If
you wind up at the same points, you are done. And, of course, inches do make
a difference - and why you should give it time until you are very happy with
the result.

Side note: AR added a center-channel to its flagship receiver as back when
stereo was "new", recording engineers often exaggerated separation as an
"Oh, WOW!" factor. And David Hafler designed the Hafler Circuit to address
that issue, which evolved into the Poor Man's Quadraphonic system. Be
careful that the signal you use is well engineered *and* well recorded.

Best of luck - you don't need any "stinking DSP" for good sound!

Peter Wieck
Melrose Park, PA