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Peter Wieck[_2_] Peter Wieck[_2_] is offline
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Default Attenuate highest highs?

Snark Warning!

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This from last year in another thread:

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.
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This pretty much summarizes my approach to speaker placement. There are overly bright rooms, there are overly dull rooms. But in the typical household, they are the rare exception. For the most part, speaker placement is bunged by practical needs such as 'the speakers can't go there because...', there by requiring compromises, not always pleasant. And in the case of Shaun's speaker/amp/sub-woofer system, I expect that electronic equalization will be the most practical solution, and also the most transferable of the options should he have to move. I admit to keeping an equalizer - but it hardly gets used as I am also blessed with an understanding wife who allows me to put the speakers where they 'want' to be in both listening areas. That one pair are Maggies makes her even more remarkable.

Peter Wieck
Melrose Park, PA