Listening Chairs
The traditional listening chair or couch has a cloth surface and a low back. The listener’s head is up and well above the back rest of the chair. The chair is fabric and has no sound reflecting properties. Armrests tend to be universal.
However, we often Queen Anne style Wing Back chairs in listening rooms. They are fabric and sound absorbing. Their high back and wrapped sides act as a sound barrier, blocking reflections from the back of the room and the sides. Quieting down the back wall reflections removes distracts from behind and tends to make for a more focused and predominant sound stage up front.
There is a clear preference with audiophiles which is to quieten down the sections of the side walls that are directly to the side of the ears. This isn’t about image reflection control it’s about reducing the directional distractions, like the rear wall but here, the walls directly to the side of the listening head. Often this is accomplished by positioning a few sound panels on either side of the listener. The Wings of the Wingback get the same job done without further damping down the room and allowing more visible wall space.
The leather versions are not the desired model because the leather creates many very early reflections that interfere with directional and clarity cues that are otherwise readily abundant in a traditional hifi set up. Leather wings also reflect strong early reflections directly into the opposite ears, similar but more intense as cross-talk reflections.
Ambience
Ambience is a time delayed diffuse condition in the upper treble range of sound. A diffuse condition exists when the reflected sound seems to have no particular sense of direction. When sound is initially being reflected it has a sense of direction, most of the present discussion about sound has been about sound that has a sense of direction.
If we wait a little longer we’ll see that the reflecting sound in the room is becoming more and more random in nature, it is becoming ambience. Diffusers in the room scatter sound and accordingly they reduce the time it takes for early reflections to be converted into ambient random reflections. Sound reflecting around a room dies out because of the absorption in the room. When diffusers are added to the room the reflections become ambient sooner than otherwise. The earlier ambience is created, the louder it is and easier to hear.
 There are two kinds of sound scattering devices, one is referred to a Diffusor which is trademarked by RPG and the other is referred to as a diffuser, anything that scatters treble range sound. The classic diffuser is a “poly”, a column that has a curved surface, not a cylindrical column but a column made out of an arc, a segment of a large cylinder. The poly diffuser is commonly used in recording studios, concert halls, auditoriums and professional listening rooms.
Stand in front of a wall, about 3’ away and perform a sound check “Check, check, testing, 1, 2, 3, 4” and as you talk at the wall you can sense you are speaking towards a wall. Stand in front of a poly diffuser, about 3’ away and talk at it, You can’t sense that your are talking towards a large flat surface. It seems like you are talking towards a sound absorbing panel because the diffuser reflection is so quiet, because it is so spread out.
The poly has a smooth, flat, curved surface. It acts like a curved mirror does with light waves. Because it is a flat curve it doesn’t have irregularities all along it’s vertical surface. The ear is very sensitive to the changes in elevation of high frequency sound, which is why a fly buzzing around is so irritating. If we had irregularities along the flat curved surface, like we see on climbing walls we would become very distracted by the multiplicity of vertical reflection points. The poly is a diffusing surface that does its work without calling attention to itself, sonically speaking.
 The poly diffuser is applied to walls and ceilings. When a poly is located at an early reflection location, the reflections appear to be absorbed because they are much quieter than a flat wall reflection. But they aren’t absorbed, they are scattered about the room. When we want to control an early reflection we can add a poly diffuser instead of a sound absorber and use that reflection to feed the buildup of diffusive ambience in the room.
PolyDiffusers work well with TubeTraps. When polydiffusers are stacked side by side where they meet is a shallow V intersection. That’s where the TubeTrap is located. The horn effect of the reflecting part of the open shallow “V” intersection between adjacent polys is erased by adding TubeTraps in front of the “V” intersection line. This creates a broad band diffusion/absorption wall, treble diffusion and bass absorption.
Vertical diffusers in listening rooms create strong lateral diffusion but do not contribute to vertical diffusion. Lateral diffusion is very interesting and easily heard by our ears which are also laterally deployed. Usually carpets in room absorb the vertical component of reflected sound leaving only the lateral component of diffusion as the remaining ongoing compliment of ambient sound.
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