Originally published in AudioRevolution.com,
August 2001, by Bryan Southard.
ASC TubeTraps
Introduction
Acoustic
Sciences Corporation, more commonly known as ASC, has been
manufacturing acoustic room treatment devices for the better
part of 15 years. Founded in 1985, ASC has become one of the
premier manufacturers of acoustic room treatments for the
home and recording studios alike, with their core products
centered around a patented tube-like design.
ASC's acoustical room treatments are designed
to absorb lower frequencies and diffuse and disperse higher
frequency information. The company provides a variety of acoustic
room treatments designed to improve nearly every sonic aspect
of your A/V experience.
ASC's TubeTraps come in a variety of sizes
and shapes. They are available in full rounds, half rounds,
and quarter rounds for corner applications. All configurations
typically stand four feet in height and come in a variety
of diameters, depending on the requirements of the room and
the frequencies that are being treated. Custom lengths are
available if necessary. ASC offers a variety of standard and
custom fabric coverings to best match your home or studio
decor. Prices range from about $200 per piece, to as much
as $700 for their largest treatments.
Arriving at a good friend's home to see and
hear his newly-completed custom Victorian theater, I looked
about in amazement. The basement theater has been designed
to replicate an 1850s Victorian theater adorned with every
period detail imaginable. My friend explained to me that he'd
start off the demo session with some music. Just before he
pushed play on his CD source, he gave me a long look of agitated
uncertainty and said, "I'm not sure, but something seems
to be not quite right." Being a good friend and not wanting
to sound snobby or overly critical, I replied, "Don't
worry, I'm sure it sounds ".
No sooner than he pushed play, I heard what
had given him such concern. His room was clearly destroying
the potential of his sound system. His stage was scattered
and images were for the most part non-existent. The bass was
fat and resonant and lacked any real definition. The room
was interacting with the sound system so poorly that initially
I wasn't sure if there was a component connected out of phase.
After a quick examination, we determined the obvious - the
room was indeed the problem.
I understood my friend's frustration well.
I had great empathy with his plight, as I was plagued with
a similar condition many years back as I converted my garage
into a dedicated audio/video room. As I constructed the space,
I looked forward to the sonic benefits of a dedicated room
void of all the anomalies caused by household furnishings,
appliances, asymmetry, and large reflective window surfaces.
Once my room was complete and my gear was properly positioned,
I embarked upon what I fully expected to be the best-sounding
system I had ever heard. "Why not?" I had the same
great gear that sounded very good in my living room and had
just supplied it with a perfect room - right? That couldn't
have been further from the truth. My soundstage was poor -
actually, for the most part, it was nonexistent. The bass
was boomy and came from everywhere. "How could this have
happened?"
I spent the next week hanging sleeping bags,
filling bookcases and placing every absorptive item I owned
in the room. Although I began to achieve a stage and some
limited bass control, I also managed to kill the room and
all of the natural ambience in my recordings. I reached a
point of great frustration. I had become obsessed with the
poor quality of my music reproduction. Reluctantly, I made
my way to my local retailers, hoping that perhaps they had
some magical secret that would fix my acoustical problems.
The sales guy looked upon me like I was some unhappy audiophile
geek, always one tweak from happiness. I asked him about room
treatments and he shrugged his shoulders and walked into the
back room. Moments later, he emerged with four half round
TubeTraps from ASC. He looked at me and said, "I don't
think that these will fix your problems, but you are welcome
to try 'em."
I brought the TubeTraps home and positioned
them at the first reflection points of both my front wall
(the wall behind the speaker system) and side walls just adjacent
to my loudspeakers. The "first reflection point"
can be easily calculated by placing a mirror on the wall and
moving it until you can see the reflection of the speaker
from your listening position.
I loaded one of my favorite CDs into the player
and sat back to evaluate the sound. I am told that I was discovered
about four hours later stuck to my chair with my disc case
open and an ear-to-ear grin on my face. TubeTraps had fixed
many of my acoustic problems. My stage was exceptionally rich
with detail, well defined, and laid back beautifully. Was
it possible that these little tube-like things had fixed my
problems this simply? Mere days earlier, I had been consumed
with frustration and held little hope of realizing my dream
of having a perfect dedicated room of my own.
This started my interest - which soon developed
into fascination - in room acoustics and treatment, a passion
that I have carried ever since. Initially, I borrowed products
from most of the major manufacturers. I tried a variety of
products from RPG, Argent, Room Tunes and more. I learned
about the technology behind each of these products and where
their individual strengths lie. Products are available in
a variety of sizes and shapes designed to correct a variety
of conditions. Before you treat your room, you must understand
a little about what is causing your problems, so that you
can better understand what you need to do remedy specific
issues.
What makes ASC products unique is their ability
to both absorb lower frequencies and to diffuse midrange and
high frequencies. There is no other product available for
your home that can provide this combination more effectively.
There are several conditions that contribute
to bad sound. Among these are standing waves, a variety of
echo conditions, early reflections, comb filtering and more.
Short of lining your walls and ceilings with specially designed
acoustical treatment panels, there is only truly one way to
combat these issues, which is to combine absorption with diffusion.
ASC has patented cylindrical devices that accomplish this.
Simply stated, a device can only effectively absorb frequencies
of a wavelength no greater than the depth of the device. In
the case of the TubeTraps, the depth is the diameter of the
tube. Tubes are extremely effective, as many of the other
available products are panel-based and don't provide the depth
to properly absorb low frequencies effectively. This is why
the panel designs focus primarily on diffusion. Diffusion
will control your early reflections, which can correct many
soundstaging issues, yet will do little to control standing
waves that simply cancel reproduced information, making your
system sound less resolute than it should.
Music and Movies
To
demonstrate the effects of the ASC TubeTraps in my room, I
started with "About a Girl," the opening cut from
Nirvana's 1994 release Unplugged in New York (UNI/DGC Records).
When removing the 11-inch tubes from the first reflections
on the front and side walls, I found the vocal images became
clouded and undistinguishable in location. When I reinstalled
the TubeTraps, the images again became solid and contained
a much more realistic tone. Kurt Cobain's voice had considerably
greater timbre and depth with the TubeTraps installed.
The TubeTraps treatments are designed to control
high-pressure waves, so I thought, "Let's give them some
waves." On Van Halen's "Panama" on their album
1984 (Warner Bros.), I found the bass and drum tracks to be
notably different. The drums, without the use of corner TubeTraps,
were fat and slow. Bass performance with tube traps had a
focused position rather than just filling the room. As mentioned
earlier, the 16-inch round corner treatments are large and
perhaps not for every room, but the benefits were unmistakably
engaging.
In the original Jurassic Park (Universal -
DTS), the scene where T-Rex makes his escape and quickly commences
to terrorize the kids in the car, the rumble of the dinosaur's
growl was clearly improved. The low frequency effects were
much better controlled and had improved definition, which
made the scene more chillingly realistic. I use dual subwoofers
that can easily overload a room, but here I found the information
to be very solid. Without treatments, the bass could become
fatiguing and somewhat overwhelming, lacking any distinguishable
definition or source.
How do I know if room treatments will
provide sonic improvements for my listening environment?
The end result of a room treatment
is a room that is void of any echoing effects. It is live
and ambient and displays very controlled bass, yet has no
inherent deadness. If you clap your hands in this room, it
will sound similar to what you'd hear if you clapped your
hands outdoors, in that the quality of the clapping is live
and has a snap or quickness, with no delayed resonance or
decay. This is easily achieved in an outdoor setting, as there
are no structures for the sound to bounce off of and return
to you. The perfect room would be eminently quiet, because
for each frequency of noise, there is a cancellation of music
in the equal frequencies and the equal sound pressure level,
or SPL. To determine the condition of your room, walk around
the space and clap your hands. Do you hear resonant echo?
Do you hear slap echo, a condition caused by parallel walls
that are void of structure that would otherwise break up,
absorb and often diffuse such bouncing waves? Slap echo can
most often be identified by a quick chirp that follows the
handclap. Do you have TVs and other items between your speakers
that can interrupt and affect your soundstage? Are your speakers
close to one wall and either not close to another, or there
is another room opening to the side of the second speaker?
These are all typical conditions we encounter in what I describe
as normal listening environments, which describes 95 percent
of the settings for home A/V systems. All of these conditions
significantly degrade your sound system's performance.
Okay, I have determined that I have some of
these conditions - how much of this stuff that you're talking
about do I need, how much is this going to cost me, and what
should I expect to hear?
The engineers at ASC are very good about assisting
you in determining which products will best control the conditions
in your room. You can also check with your retailer to see
whether they can help provide you with the technical information
you will need to properly treat your room.
I will share a couple of scenarios, and provide
you with my recommendations for the best and most effective
solutions. Please understand that these are only generic recommendations
intended to give you a baseline for understanding which products
you might need, what treating your room acoustically is going
to cost you, and what results you should reasonably expect
to achieve.
The first condition that needs to be addressed
is controlling echo. There has been a trend of late to create
large rooms in our homes, sometimes combining a two living
rooms into one larger room, often called a "great-room."
This can be particularly troublesome because these rooms are
very big with very large walls, often with vaulted ceilings.
If this is your situation, you will definitely want to consult
with the engineers at ASC. This condition can be extremely
hard to remedy sonically. Echo is the most degrading condition
in any room. Before we test and treat this condition, let's
look at a package that will benefit absolutely every room.
Once we understand this basic treatment package, we can assess
the need for additional acoustical treatments. As a minimum,
I recommend four 11-inch round TubeTraps, one at each of the
first reflections on the side and front walls. These will
control most troublesome early reflections, providing large
improvement to your soundstage. You will be absolutely amazed
at the noticeable lift in sound quality that this will provide
in nearly all rooms. The price of the 11-inch diameter, four-foot-high
rounds is $328 each. You could consider half-round TubeTraps
at $248 if space is a concern, but you would sacrifice performance.
The half rounds tend to look a little more planned and sleek
in your room, but the performance of the full rounds is superior
and will provide you with better control. Once you have treated
the first reflections, it is time to ascertain whether you
have slap echo. As you walk around your room and clap, you
will likely hear echo in select areas. If that's the case,
you will want to consider wall panels. These are designed
to diffuse sound waves and work very well for this application.
Wall panels measure eight inches wide by four feet tall and
cost $398 for a package of eight. Wall panels can also be
purchased in smaller or greater quantities if you need additional
treatment. To make the most effective use of the panels, I
suggest that you position the panels on the walls in the specific
areas you determined you were experiencing the slap echo.
You'll want to mount the panels so that they are spaced one
panel width apart on each of the side walls, staggered by
one panel width on the opposite walls. If you were to shine
a light from a panel on one side wall to the other side, you
would hit a space between the panels in the parallel pattern
on the other wall. You might call this an offset pattern.
This will control slap echo very well and allow for little
to no cancellation in your reproduction.
There are relatively few rooms that don't
suffer from large standing waves. This is a condition that
will cloud your bass, making it soft and robbing it of dramatic
impact. Treating this condition is not cheap and takes up
considerable room. To treat this, I would suggest 16-inch
diameter, four-foot high rounds in each corner of your room.
As a minimum, you can put one in each of the corners behind
your speakers, but treating each of the four corners is preferred.
The 16-inch rounds cost $498 each per treatment. As mentioned
before, these are generic conditions, but these examples are
intended to provide you with an understanding of what treating
your room will cost.
With the above treatment set, you could expect
to experience large improvements in every area of performance.
You will likely experience a considerably more palpable midrange
and greatly improved vocal timbre. Instruments will have greater
depth and greater three-dimensional textures. I would expect
your bass performance to improve dramatically in definition
and focus. Ideally, individual room conditions will be analyzed
separately and optimized for your specific environment. The
above recommendation is a typical building block to an ideally-treated
room.
Conclusion
A
great-sounding, high-performing A/V system is the result of
more than just great gear. It's a combination of good components,
accurate setup and, foremost, a room that performs to the
caliber of your reproduction system. Poor room conditions
plague just about every A/V system. It is likely responsible
for more loss of sonic performance than any other aspect of
your system. Too often, we seek to gain improvement through
the purchase of additional gear, or upgrading to more expensive
gear, and don't realize that we are really overlooking the
real problem. You room is the catalyst of your sound system.
The performance of your gear is no better than your room.
If your room is performing poorly, you are simply wasting
your money on expensive gear. Room treatments are seemingly
expensive and many may decide that they don't want this stuff
in their living rooms, which is very understandable, but for
those who can tolerate the intrusion, the benefits are immense.
Many retailers will loan you ASC products
to try - speak to yours and see if he or she will cooperate.
If there are no convenient retailers, then I would strongly
recommend the purchase of a minimum of four 11-inch tubes.
I stand behind this recommendation as much or more than any
recommendation that I have ever made. For myself, I couldn't
live without my ASC TubeTraps, as they provide essential improvement
to my room and provide the correct foundation for evaluating
A/V gear. I often invite manufacturers to my home and they
are consistently staggered by the performance of their products
in my room. For most home applications, TubeTraps are the
difference between a good sound system and a great one.