Tips & techniques on room tuning as presented by PMI and our very own McIntosh Experience room becomes a case study.
For our recent Ask the Experts event, Anthony Grimani and Terry Hill, from PMI and MSR Acoustics, spent the evening in our recently renovated McIntosh Experience room with a large group of interested audio fans intent on learning more about room acoustics and how to tame them for a better listening experience. The science of acoustics has been around for a very long time, but only recently have companies like MSR Acoustics simplified the process of choosing the proper panels and materials to effectively treat a room’s acoustics and enable the best sound possible.
A great case in point is our very special room at Century Stereo called The McIntosh Experience. As one of the first two Experience Centers to be created by the venerable high-end audio brand, McIntosh Laboratory, the room serves as a center for experiencing the impact and power of one of the industries most revered brands. But while the room looks beautiful and the array of McIntosh gear dazzles and amazes; the acoustical character of the room was not ideal for an optimum listening experience. With high ceilings and reflective surfaces, among other issues, there was a terrible echo throughout and a lack of good bass in some parts of the room.
Century Stereo has worked with MSR Acoustics & Anthony Grimani for years on client projects and even contracted him years ago to treat another problem studio in our showroom so naturally we reached out to the MSR team to prescribe the right mix of panels and placement techniques to improve the sonic presentation of the room. MSR hustled to design a layout and deliver an array of absorber panels, diffusers and ceiling panels along with a couple of Spring Traps (to improve low bass handling) and our Century Stereo technicians were able to install the panels and ready the room just in time for our Ask the Experts event.
The natural question that you are probably asking is “Do things like panels and such really make that big a difference when listening to equipment as good as McIntosh?” The answer is YES! Which was reinforced in every person’s view who has listened to the room before and after MSR got their hands on it. The fact is that the quality of the gear cannot overcome the anomalies of the room. In other words, just because you buy terrific equipment, its performance is still subject to the acoustical conditions that are present in the room. That is why room tuning treatments are necessary to control the room’s listening characteristics for best sound performance.
Century’s General Manager, Rick Bronner said, “Let Charlie (McIntosh President – Charles Randall), know that everyone who has heard the difference is astonished by how much better it sounds.”
Comments from the salespeople echo Rick’s observations as well noting:
Movie dialogue seems to be right in front of my face. Significantly tighter bass. Greater clarity and detail. Music seems to be cleaner and clearer. It is as if the walls of the room disappear for an expansive open feel.
Tips & Techniques
So how did these panels render such magic? What black science did they conjure up? The truth is – MSR used good design and the physics of sound engineering to improve the listening experience. Here’s an overview of the techniques and tips on room control that we learned about that night.
First, we learned at the event that bass performance is the most obvious example of room acoustics affecting sound quality. Today’s high quality speakers and amps can put out tremendous quantities of low bass energy and everyone loves the rumble and thunder of movie soundtracks that are the signature of Hollywood blockbusters. But rooms at home are much smaller than movie theaters. And the bass waves that are being produced are very large. They actually bounce back and forth in a typical home theater – reinforcing in some places – and canceling out in others. To smooth out this bass response and make it sound cleaner and tighter, special devices are needed to absorb and dissipate this excess bass energy. MSR patented a device called a SpringTrap that actually flexes to absorb the impact of the low bass waves, and then dissipate the acoustic energy as heat. The result is cleaner, tighter bass performance in the room. Usually placed in corners – where bass energy is at its peak, SpringTraps are the most effective bass control mechanism on the market – with peak effect between 40 and 100 HZ. Bass filter panels are also used to absorb some of the bass energy – but of slightly higher frequency range. When used in conjunction with the SpringTraps, room acoustics are improved to be much more conducive to terrific bass performance.
Next, we learned the most critical factor to control is sound reflections in the room. To make a very complex science simpler, think about your listening experience this way: Once you buy some terrific speakers and great amplifiers, the goal is for you to hear the sonic experience they create. Thousands on man-hours have been put into their design and manufacture to enable them to create the illusion of music floating in space between the speakers. That only happens if the majority of what you hear comes directly from the speakers. The problem is that the sound coming out of the speakers also goes everywhere else around the room. Every surface the sound waves hit creates a bounced sound wave that goes off everywhere else again. Your ears also hear these sounds – slightly delayed from the original signal – and second arrival (and third and fourth, etc.) are confusing to the brain. What should be a crystal clear image between the speakers, or up on the screen, becomes muddled and unclear. To treat these unwanted reflections, absorption panels are strategically placed.
However, there is such a thing as having too much absorption in the room which is equally bad and rooms that have absorptive material all around the room just sound too dead and unnatural. And the live end / dead end technique popular years ago is also not the right way to design acoustical treatment. The truth is you only need to cover about 20% of the wall surface with absorptive material and 20% of the walls with diffusive material. The goal is simply to control the reflected sound – not eliminate it. And the ideal placement of these special panels is to place absorption at the point of first reflection, and then alternate diffusion and absorption as you go around the walls. The diagrams will give you a much better idea of the technique.
Last, all this talk of acoustic panels on your walls may conjure up images of an anechoic chamber, which some of you probably dig but for those of you that really don’t want to see the panels and materials themselves there are several ways to integrate these solutions into your decor. From clever use of color choices and lighting that make the panels blend into wall or through the use of stretch fabric walls where the speakers and sound panels are all hidden behind “walls” of stretch fabric mounted on a framework. There are a myriad of design techniques that will provide a look that is sleek and clean, while the acoustical performance is superb.
We hope you enjoyed hearing about our exciting event with MSR and the renovations in our McIntosh Experience Room. Please make it a point to come by and hear the difference for your self. We are scheduling home visits to check out listening rooms all around the area – so we can make suggestions how proper room acoustical treatment might be able to improve the entertainment experience. Please let us know if you have any questions you’d like answered – either by our staff of experts – or by the savvy crew at MSR.