Near field listening and speaker placement


We have a large music room (20x30) with a cathedral
ceiling and front outside wall angled out at 105 degrees,
(typical contemporary) with a tall bank of windows. In
order to avoid interaction with the glass, speakers must
be placed along short (20FT) axis of room. The room is
live (hardwood floors), although we have thick wool 9x12
rug in front of speakers

We would like to use a near field listening configuration,
and have several questions:

1. We assume nearfield listening is an attempt at zero
interaction with boundaries so that only direct path sound
arrives at the ear. Is this the consensus, or have we
overlooked something in the definition?

2. Speakers are placed 6 feet from the "back" wall. What
is the result of eliminating the back wall from the
listening equation?

3. In order to minimize interaction with the floor (the
closest boundary) should we worry about carpet on the
sides and behind, not just in front of our speakers?

4. Are there a canonical set of rules for spatial
optimization in near field set ups?

Guidance from the experienced is much appreciated.
hindemith

Showing 1 response by subaruguru

Was about to state Soix's point.
I listen to 3-ways in a 7.5' triangle in a 14x24 room.
The speakers are 8' out from the front wall.
I tried several serious 3 ways (N803, N804, Ariel 8, Revel F30, VA Fidelio) before deciding upon my choice (Parsifal Encores).
The Ariels and ESPECIALLY the Nautilus' had SERIOUS problems in the nearfield due to lack of coherence. The Revel F30 was pretty darn good, but my wife hated the California moderne looks. The Fidelios didn't work because their rear-firing woofs needed boundary reinforcement, and 8' is WAY too far away. So this can get tricky unless you take the easier route with excellent two-ways or at least 3-ways with a low cross.
Damping the room much more than you have is my strong preference, but you may be able to get decent sound in the nearfield. Controlling sidewall splatter with toe-in and speaker selection for off-axis response characteristics will be important. (You DON"T at all have to have a headphonesque stage...quite the contrary.)
I'm fortunate that my 7.5' triangle throws a stage about
12' wide and easily 10-15' deep!---WAY beyond the speaker positions. I use stuffed sofa and chairs with throw pillows
propped on top of them where windows and fireplace are at first reflection points. Wall-to-wall with pad is HIGHLY recommended, and a cross-beam ceiling doesn't hurt either.
By contrast my 14x14 cathedral-ceilinged hardwood-floored, multi-windowed familyroom system sounds like crap!...but it sure plays loudly! For TV that's fine...makes the "action" seem bigger, and for 2-channel HT that's ok.
But for serious music reproduction deader is better, and to repeat, ultra-coherent speakers in the nearfield just improve your odds of aquiring a stage and frequency-response
close to the designers' intent.
Good luck.