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Sound Absorption Behind and Between the Speakers?

Recently my system moved to a new listening room and I was not enjoying the sound very much. There is a window between and behind the speakers. Last night, I put three sound absorbing panels right in front of the window and added a couple salt lamps which illuminate the panels. The sound instantly became way better! I have a soundstage now! I am not sure why though. Do the absorbing panels really have that much of an effect? Or does the fact that I added the panels with the salt lamps give my mind a surface to project the soundstage on which makes a bigger difference? Bit of both?
mkgus
jbrrp1
423 posts
 
I once had a fireplace in the middle behind my speakers with glass doors on the enclosure - - it did great damage to the soundstage due to first reflection point issues.  Absorption worked for me then for dedicated listening sessions (but really did not work for my SO!).  Now in a dedicated room I have a wall with GIK panels behind the speakers and I enjoy a deep and expansive sound space.  Maybe deflection would work even better, but I love my art panels - - much more interesting to look at for me!  I also employ absorption at the side wall, ceiling, and floor first reflection points.
hilde45's avatar
hilde45
5,235 posts
 
@rego and others,

Rego pointed out that:

the reason for treatment on the front wall is to control first reflections and then help on the axial direction.

If the time it takes for the first reflection behind the speakers is longer than the time it takes the sound from front of the speakers to my ears, why would I need to treat them?
rego
378 posts
 
Smearing is the term of reference that I see used ... the reflections still have energy ... in a room that is very 'bright' this energy is at higher levels longer.
This is about reinforcement and interference interactions.
The reflections do not stop at the first reflection but go on to two, three and lot more.
These are all ripples at many frequencies in the pond that is the listening space ...
unsound
7,344 posts
 
Though the drivers appear as though only front firing, the sound produced is somewhat omnidirectional, especially as frequencies decrease. Typically  speakers are placed so that the wall behind them is closest. The ear/brain mechanism can discriminate between direct and reflected sounds so long as there is about 5 ms between them. If the sound bouncing off the wall behind the speakers (typically the closest wall) is too close, then there isn’t enough time between the direct vs. reflected sound and the sound converges to smear the perceived direct sound. Hence, sound treatment behind and between the speakers.
hilde45's avatar
hilde45
5,235 posts
 
@rego and @unsound 
That helps. I moved my speakers far enough off the front wall so that there'd be enough of a delay and I wouldn't get the reflected sound *before* the direct sound.

Still, Rego's point is valid. The whole room is still full of energy/information and that can get into the mix, even if it's not interfering, initially, with the direct sound.

That's how I understand what you're saying, at least.
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