Archive for category Home Theater
Posted by Acoustics First in Absorption, Auditorium, Home Entertainment, Home Theater, Multipurpose Rooms, Music Rehearsal Spaces, Music Tracking Room, Press Release, Product Applications, Products, Recording Facilities, Recording Studio, Studio Control Room, Theater, Uncategorized, Vocal Booth, Voice Over, Worship Facilities on May 24, 2021
Bass frequencies are difficult to control… and there is sometimes a tendency to overuse standard, broadband panels to try to absorb everything in order to get rid of that bass. However, this method is unbalanced and has the side-effect of leaving a room sounding muffled and boomy.
Physics! High frequencies are easier to absorb than low frequencies. So, when you ONLY use broadband absorbers, they easily remove the high frequencies and leave more of the lows. Overusing broadband absorption in a large performance space can be a disaster – leaving an environment lacking energy and feel – many describe this condition as a room sounding “dead.” (Not good!)
So how can you treat the boomy bass without killing your rooms with too much broadband absorption? Can you just take out the bass? Unfortunately, it is impossible to ONLY absorb the bass, but we can LIMIT the amount of high frequency energy that we absorb to balance out the response.
Acoustics First® presents… the Sonora® LFC – Low-Frequency control panel.
The Sonora® LFC looks like a standard Sonora® Wall panel, but looks can be deceiving! At 4-1/8″ thick, it is virtually indistinguishable from a High-Impact Sonora® panel – however the interior structure of the LFC is optimized to attack the bass frequencies and smoothly roll off the high frequencies. Let’s take a closer look at the performance difference between the Sonora® LFC and the standard Sonora® panel.
When you look at the performance charts, you will notice that the standard 4″ Sonora® panel starts to “roll-off” in the lower frequencies below 125 Hz – it still absorbs them, just to a lesser degree. We designed the Sonora® LFC panel to focus on those frequencies below 125 Hz – while allowing the other treatments to handle the rest! This allows you to use fewer broadband panels, and still have some high-frequency energy for diffusers to spread around – thus creating a more balanced acoustic environment.
The Sonora® LFC is an engineered solution using the same high-performance materials as our other products, but combining them in a way that optimizes them for Low-Frequency Control – hence Sonora® LFC! The magic is in the way those materials are used.
All of the materials used in an acoustic environment have a function – “Diffusers,” “Absorbers,” and “Bass Traps” are all general descriptors of product functions. Some diffusers are also Bass Traps. Some bass traps are also broadband absorbers. Some diffusers use absorption for amplitude grating. By combining a dampened, resonant trap with multi-density fiberglass, the Sonora® LFC focuses on making acoustic spaces more balanced. For controlling the bass without sucking the life out of a room, the LFC Panel is an outstanding tool for refined Low-Frequency Control!
There are many home theaters of note, but rarely is one created (at this scale) by the singular dream and dedication of one man. Ken Fritz involved Acoustics First® early in the project to perform acoustic measurements of the space, and his theater became the first large-scale installation of our newly developed HiPer® Panel. From beginning to end, Ken says that he spent more than 25 years on the realization of his dream – and others have taken notice.
There have been numerous write-ups of Ken’s theater, which was constructed (from the ground up) specifically for this purpose. The walls are hurricane grade block construction, the roof-line is constructed to improve the acoustics, the walls are clad in HiPer® Panels, the bass emanates effortlessly from in-wall enclosures – and just look at those custom built arrays that Ken designed and constructed by hand! This project is more than just a labor of love, it is an obsession with excellence.
This obsession covers every aspect of the room and the system, with everything being either built by hand, customized to his specifications, or simply the best you can get! If there is a “home theater mountain,” Ken built a skyscraper at the summit – but don’t take our word for it…
You can watch the one-hour documentary telling the story behind the dream – in Ken’s own words.
Adding Nouveau™ wood diffusers to a home theater is not as daunting a task as it may seem, and can be done with a little planning and a few tools. This install used an ingenious mounting method to ease the final install. Instead of mounting the z-track to the wall directly, it was mounted to sheets of plywood which were hung with Gorilla/Hercules hooks.
The first task was to pick a stain. You can use the back of a plank to get an idea of how the poplar will respond to the different options. Poplar has a very interesting and varied structure that will take stain differently than some other woods. Darker stains may be more consistent, but don’t reveal the character and variation in the wood. This install chose a Smoke Gray which grayed out soft areas and browned the harder heart wood. A semi-gloss clear coat was used to finish.
While the stain dried, the mounting plywood was cut down to hide behind the planks. Four hanging straps with eye-loops were then added to the top edge of each of the plywood sections, and spaced to avoid studs.
The Z-track that would normally be installed on the wall was installed on the opposite side of the plywood. This will make it easy to hang the Nouveaus onto the sheet after it’s on the wall.
After the Nouveau™ planks are finished with the staining, and left to cure for a few days, they are ready to have the mating Z-bars attached to the back. They are installed with the same spacing as the Z-tracks on the plywood sheets. This will make it easy to align them after the plywood is hung on the wall.
The Gorilla/Hercules Anchor hooks are rated to around 50-60 lbs each. The Nouveau™ planks are roughly 25lbs each (at 48 inches) and each section has 4 hooks supporting 4 planks plus the weight of the 3/8″ plywood. The hooks are installed so that the plywood will hang level – with the weight distributed evenly across all four hooks.
Finally, the Nouveau™ planks are installed into the Z-Tracks on the plywood, and moved into position. Because the z-bars were installed square and level, there is no shifting, and they hang true. The undersized plywood sections disappear behind the planks leaving the impression that the planks are floating slightly off the wall.
While this mounting method may not be ideal for every scenario, this was an effective way to install 8 Nouveau™ planks with only 8 small hook holes in the wall. These can now be installed in apartments or temporary environments with minimal damage to the existing walls – and once you are done, they’re easy to take down and reinstall somewhere else. You just need a level!
Here’s one of the first install pics of our new Aeolian™ Sound Diffusers, installed in a home project studio. Also note the Art Diffusor® Models F & C, in the ceiling and behind the speakers respectively. This is obviously a diffuser connoisseur’s room.
Below shows the room after the Sonora® products are installed.
For anyone new to the world of acoustics, there is a multitude of terms, coefficients and numbers that are thrown around. This flood of information can seem intimidating, especially to beginners. In this series, acoustician Cameron Girard of Acoustics First® hopes to help you distinguish between what’s useful and what’s not.
Part 2: How Mounting in Testing Affects Sound Absorption Data
As I discussed in my previous article, the best way to compare the performance of sound absorbing panels is by referencing the Sound Absorption Coefficient (SAC) and Noise Reduction Coefficient (NRC). However, these coefficients are often used as marketing tools. Be on the lookout for companies that list absorption coefficients and NRCs without mention of a particular testing standard or mounting method. It’s vital to check for this information, as direct comparisons to competitors and other materials can only be made if their testing procedures are the same.
The sound absorption of a material that covers a flat surface not only depends on the physical qualities of the material but also on how the material is mounted during installation. The mountings specified in laboratory tests are intended to simulate conditions that exist in normal use, such as direct wall mounting and installation into a ceiling grid.
Many materials for treatment of walls or ceiling are tested using what is called Type ”A” mounting. Type ”A” mounting means the test specimen was placed directly on the test surface of the reverberation chamber. Lay-in ceiling tiles, on the other hand, are often tested using ”E400” mounting. The ”E” designates a sealed air space behind the specimen (simulating the air gap between a dropped tile ceiling and the structural ceiling) and the number after the ”E” is the depth of the airspace in millimeters. The airspace behind the acoustic material affects the sound absorption by acting as a bass trap. The deeper the cavity behind the panels is, the lower the fundamental of the “trapped” frequencies will be.
To see what this look like in terms of actual numbers, let’s take a look at how different mounting methods effect the sound absorption coefficients of Acoustics First’s HiPer® Panel (a low-profile, composite absorber/diffuser panel).
Since the HiPer® Panel can be used effectively in multiple applications; we had it tested in accordance to the two most-common mounting procedures, Type E-400 and Type A. The results of the laboratory tests are as follows:
Sound Absorption Coefficients
|1″ HiPer® Panel||1″||E-400||0.43||0.28||0.51||0.76||0.99||1.10||0.65|
|1″ HiPer® Panel||1″||A||0.09||0.28||0.78||0.75||0.94||0.85||0.70|
As you can see from the chart, the sound absorption coefficient at 125 Hz varies greatly between E-400 mounting (SAC of .43) and Type-A mounting (SAC of .09). If mounting the HiPer® Panel in a ceiling grid, with a sizable airspace, you can expect significant low-frequency absorption, but mounting it on a wall (Type-A) will result in much less absorption at 125Hz.
Other mounting methods are available, but are not used as frequently. Here are some of the basic mounting designations (See ASTM E795 for more information.)
Type A mounting – Test specimen laid directly against the test surface (wall panel on drywall).
Type B mounting – Test specimen cemented directly against the test surface. Type B mounting is intended to simulate acoustical ceiling tiles or other sound-absorptive products adhered to a hard surface with an adhesive.
Type C Mounting—Test specimen comprising sound-absorptive material behind a perforated, expanded, open facing or other porous material.
Type D Mounting—Test specimen mounted on wood furring strips.
Type E Mounting—Test specimen mounted with an air space behind it (dropped tile ceiling).
As we’ve discussed, acoustical data can vary greatly depending on the mounting method used during testing. Acoustics First tries to include as much information about testing procedures as possible, because we feel an informed client makes the best client.
Contact Acoustics First for your all your sound control needs!