Eighth Nerve - Response Controller
Acoustical Products
Room
acoustics play an important role on the sound quality of any audio system.
Windows, hardwood floors and other highly reflective surfaces cause secondary
reflections and echoes that tend to defocus and blur the sonic image we
try so hard to create. Surprisingly, simple room treatments help reduce
these problems by absorbing sound which would otherwise be reflected back
into the room. Sonic improvements can be made by treating the room at
specific locations to reduce unwanted reflections.
This not only applies to home theater sound, but also the more traditional
two channel systems as well. A company called Eighth Nerve, located in
Nashville, Tennessee,
has introduced a series of Response Controller specifically addressing
these problems.
Bill Laurent, President of Eighth Nerve, sent us a set of Ivory colored acoustic response controllers to try out in our listening space. They are available in Ivory or Black. They included Corners, Echoes and Seams. Corners are used where the two walls meet the ceiling, so four of them are needed in a typical room. Echoes are placed on flat surfaces to help reduce "Slap echo" locations caused by two parallel walls facing each other. A simple test to hear the effects of the echo is to clap your hands while standing between the two parallel surfaces. You should hear the slow decay of sound as a result of the sound bouncing back and forth. This is a common problem in most listening environments. The Echo controllers are usually mounted on the front and back walls as well as the side walls to reduce the echo problems. They are also used to reduce "mirror points" in the room where sound is reflected off the side wall and hits the listener slightly later than the direct sound from the speaker. Imagine the wall being a mirror and you look at it and see your speaker. This is the location of the "mirror point" that reflects the sound. This causes blurring and imaging problems in many setups. The Seams are used to control energy traveling along the wall surface. They are mounted equal distance from the floor and ceiling. All of the products we received use push-pin tacks to hold the controllers in place. This is a better approach than the double sided tape since adhesives tend to ultimately fail over time.
Performance
Using our Sencore SP295C Audio Analyzer, we measured RT60 times both before
and after the installation of the Response Controllers and we saw a reduction
in the reverberation time. Our listening room has a nasty reflection on
the right side wall and the installation of two Echo panel helped
reduce the level of the secondary reflections. We measured this using
the SP295C, which sends out a pulse and looks at the incoming sound wave
and converts it into a Time/Energy graph. We could clearly see the fundamental
arrival of sound and the secondary reflections. This is a great way to
tune a room. By attenuating the primary reflections and other mirror points
in our room, we were able to improve the intelligibility and image coming
from our speakers. Two channel audio as well as movie soundtracks were
certainly more enjoyable once we added the controllers to specific locations.
Acoustic Response
Controllers can make a significant difference in how your audio system
performs. What we liked about the Eighth Nerve product was the great performance
we got for the relatively low price. For under $270 you can pickup a Roompack
that includes four Corners, four Seams and 2 Echo
products. Additional controllers are available for your specific needs.
Eighth Nerve also has framed response controllers designed for higher
sound pressure levels, but we didn't have any for this review. If you
take your room acoustics seriously, you should set aside part of your
budget for some affordable Eighth Nerve Response Controller products.
Depending on your room acoustics, you may be surprised at what a difference
it can make.
- Kevin
Nakano