WILSON AUDIO Watch Surround 2 Series, Руководство пользователя

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W A T C H S
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W i l s o n A u d i o S p e c i a l t i e s
slightly asymmetrically in the listening room. This is so the standing waves caused by
the distance between one speaker and its adjacent walls and floors are not the same as
the standing wave frequencies excited by the dimensions in the other channel.
Comb Filter Effect
The “comb filter” effect is a special type of standing wave noticeable primarily at
higher frequencies and shorter wavelengths.
Acoustical comb filtering occurs when sound from a single source, such as a loud-
speaker, is directed toward a microphone or listener from a distance. The first sound
to reach the microphone is the direct sound, followed by a delayed, reflected sound.
At certain frequencies, cancellation occurs because the reflected sound lags in phase
relative to the direct sound. This cancellation is most apparent where the two frequen-
cies are 180 degrees out of phase. Further, there is augmentation at other frequencies
where the direct and the reflected sounds arrive in phase. Because it is a function of
wavelength, the comb filter effect will notch out portions of the audio spectrum at lin-
early spaced intervals. Subjectively, comb filter effect evidences itself as follows:
• Added roughness to the sound
• Reduction of harmonic richness
• Smearing of lateral soundstage, image focus, and placement
Comb filter effects are often caused by side wall reflections. They are best con-
trolled by very careful speaker placement and by the judicious placement of Illbruck
Sonex® or air duct panels applied to that part of the wall where the reflection occurs.
Section 3.3 – Resonances
Resonance in listening rooms is generally caused by two sources: