Posts Tagged Model F

Eight very different 2′ x 2′ sound diffusers.

Acoustics First® has maximized the idea of adaptable designs. One of the most common modular architectural elements is the 2′ x 2′ ceiling grid. While standard, fiber ceiling tiles have their uses, specialized acoustic environments require higher-performing materials – for both absorption and diffusion. While Acoustics First® excels with its Sonora® and Cloudscape® Ceiling tiles, today we are going to focus on the wide range of 2’x 2′ diffusers that have been developed over the several decades.

Sound diffusers in a 2′ x 2′ format have several advantages, other than just being placed in a ceiling grid to help diffuse the ceiling. They integrate well on walls and in arrays, where they can help break up large flat surfaces and help minimize flutter and standing waves from parallel surfaces. While they provide many different aesthetic options, there are also many different functional types of diffusers available in this form-factor to address different acoustic issues, from flutter, bass issues, targeted frequency absorption, and geometric scattering. Let’s look at some of these devices and their uses.

Geometric Diffusers.

Geometric diffusers have been around a long time. These devices break up large flat surfaces and redirect or “scatter” those reflections in different directions. They work great in environments where you need to redirect acoustic energy in a predictable way, and redistribute a specular reflection over a wider area. In a 2′ x 2′ size, you can also get a fair amount of bass absorption, due to the large cavity behind the geometric shapes creating a space that can be stuffed with absorbent material to tune it.

The Pyramidal Diffuser is a classic geometric shape that provides 4 surfaces to break up the acoustic energy, these facets are also asymmetric, which prevents lobing, and reflects energy in different directions.
The QuadraPyramid™ offers the same benefits as the pyramidal, but in a lower profile, and 4 times the number of faces in the same footprint. These offer more control over high frequencies, that respond well to the multitude of smaller faces, due to their shorter wavelengths. These work well in spaces with lower ceilings to help control flutter echoes.
The Double-Duty Diffuser™ is a polycylindrical barrel diffuser, which redirects the energy in a hemispheric pattern. This pattern is easy to predict when trying to help distribute energy to many people – either in an audience, or players in an orchestra. This has the added benefit of a large cavity which works well as a bass trap.

Quadratic/Mathematic Diffusers

Mathematic diffusers are devices that use specific calculations to design their size, shape, and structures to effect their performance. A common type is called the Quadratic Residue Diffuser (sometimes called a Schroeder Diffuser, after its pioneering inventor, Manfred Schroeder). This type uses a Quadratic Residue Sequence that optimizes uniform sound diffusion at specific design frequencies. There are different ways to implement these designs, but two common designations are based on their diffusion patters – 1D or 2D. A 1D Quadratic diffuser mostly spreads energy in one plane, and a 2D provides a hemispheric pattern.

The Quadratic Diffuser is a 1D Quadratic Residue Diffuser that diffuses across the wells. This pattern looks similar to that of a Double-Duty diffuser, but is more disruptive to the phase relations of the reflections and is tuned to a narrower frequency band. These diffusers are often installed with the wells up in the ceiling or wall, which means they do not protrude from the surface, providing a clean flat look.
The ArtDiffusor® Model C is a high-performance 2D Quadratic Diffuser. It uses blocks instead of wells, and has angled caps to further assist the development of the hemispheric diffusion pattern. The Model C is a hybrid Quadratic and Binary design. It is quadratic in the heights and binary in the distribution. This unique combination of mathematic functions and the inclusion of angled reflections adds a new dimension when installing arrays of diffusers to reduce lobing and improve performance.
The ArtDiffusor® Model F is an interesting spinoff of the Model C. The Model F is a specialized low-profile version of the Model C, which uses smaller block structures to tune it to higher frequencies. Like the QuadraPyramid above, the larger number of smaller surfaces tunes this device to frequencies with a shorter wavelengths, in a low-profile design. The Model F is ideal for controlling flutter, ringing and high frequency comb filtering artifacts in spaces with limited space, or specific constraints.

Organic Diffusers.

Organic diffusers are a variation on the classic mathematic diffusers which use different mathematic functions to optimize the diffusion further by creating a smooth transition. Once such method is called Bicubic Interpolation. Instead of having the math restricted to having blocks at certain heights, the interpolation bridges these heights using a function that provides a smooth transition to the next target height. This transition creates unlimited resolution in the frequencies within it’s functional range, providing expanded uniformity throughout its range, and increasing its capabilities. As different frequencies are affected differently depending on their wavelength – the organic diffusers have no hard edges to define their pattern and look differently to different frequencies and energy from varied sources.

The Aeolian™ Diffuser is, at its core, a classic quadratic diffuser. The main difference is that, instead of limiting itself to the standard blocks and wells of a single size, the surface has been modified using bicubic interpolation. So instead of every frequency interacting with 2″x2″ blocks, they hit a rolling organic surface, which will redirect different frequencies in different ways. The different wavelengths interact and reflect off the surface differently – short wavelengths are more specular and longer wavelengths find a larger section of surface to redirect them.
The ArtDiffusor® Model D is another organic diffuser design, but it uses several different modifications to the standard quadratic design. Most quadratic diffusers start with square or rectangular blocks and wells. The Model D started life as rings of different sizes and spacing based on Maximum Length Sequences that were different thicknesses. Those rings were then raised to different heights based on the Quadratic Residue calculations. Randomness was introduced with Boolean logic, which would add height to some rings while subtracting from others when they crossed each others path. The whole geometry finally went through the bicubic interpolation to smooth the transitions. This completely original design is optimized for mid-to-high frequency diffusion and maintains a highly asymmetric diffusion pattern from any angle, at any frequency within the design range.

These diffusers all have the ability to be used in different types of installations for different reasons. Many of these diffusers are mixed and matched in the same room. You will see these on the walls or ceiling, and placed in different locations. There are rooms with Double-Duty diffusers for low frequency control, Model C for Mids, and Model F for flutter, while other rooms may have Aeolians™ on the rear wall and Model C’s and Model F’s to control the ceiling.

Big 3 Studio has Aeolians on the rear wall and black Model C’s and Model F’s on the ceiling above the console.

Keep in mind, these aren’t even all the diffusers we have available, these are just the ones specific to the 2′ x 2′ format. The Aeolian™ has a 1′ x 1′ version called the Aeolian™ Mini. There are flat panel diffusers that are hybrid absorbers and diffuser like the HiPer Panel® and the HiPer Panel® Impact. There are even large format versions of the Double Duty™ diffuser, Pyramidal, and even the Quadratic Diffuser.

For more info about these diffusers, read some of our, “Similar, Yet Different Series,” where we go into more detail about our products… and how some of these are similar, yet different!”


If you have any questions as to which products you need to optimize your space, reach out to Acoustics First® and we can help you find which products will be best for your application. Remember that Acoustics First’s® full line of sound diffusers are all made in the USA, with many available in stock for quick shipping.

, , , , , , , , , , , , , ,

Leave a comment

ArtDiffusor® Model C and Model F – Similar, yet different.

Model C vs Model F

We often get asked about the functionality of the different diffusers, and one of the frequently asked questions is about the differences between the ArtDiffusor® Model C and ArtDiffusor® Model F.  We will cover some of similarities and differences in the design, functionality and use of these two devices.

Design.

The Model C and Model F use identical math to come up with their basic structure, they even have angled faces – the main difference between the two is that the Model F elements are ½ of the Model C’s height, length and width – and then it is duplicated 4 times in the same footprint…  The Model C is nominally 2’ x 2’ x 4” deep.  The Model F is four quadrants that are nominally 1’ x 1’ x 2” deep – like little scaled down Model C’s… This makes them visually similar and aesthetically compatible.  This low profile design makes the Model F more desirable for ceiling installs in spaces with very limited headroom – like basement studios that have low ceilings.

 

Performance

Due to the different size of the elements on the two devices, they have very different frequencies at which they are most effective.  The Model C is a mid-frequency diffuser by design… having larger elements and deeper wells than the Model F.  The Model F is primarily a high-frequency diffuser, due to the small elements and lower profile.  Both diffusers are tuned to different frequencies as their “primary range,” and while they do affect lower and higher frequencies than they are designed for – it is to a lesser degree, or the product of absorption.

What does this mean?

The Model C has a primary design range of 1KHz to 4KHz.  This is where it is primarily designed to work.  It can and does diffuse below 1KHz and over 4KHz – just to a lesser degree than its primary design range.

The Model F has a primary design range of 2KHz to 8KHz, and again, it does diffuse outside of that range, but to a lesser degree.

The angled caps of both the Model C and Model F help to extend their high frequency range by reflecting sound in different directions at higher frequencies – causing the sound to scatter spatially.  The different heights of the elements cause sound reflections to be offset “temporally,” or in time. The sound that hits the higher elements is reflected sooner than the sound that hits the lower elements – travelling further before it is reflected.   This time offset, changes the “Phase Coherency” of the reflection; the larger the difference in the heights, the greater the offset in time.

The size of the elements matters as well. The shorter wavelengths of high frequencies can diffract and scatter off of the smaller elements of the Model F more readily than low frequencies, which see the Model F as a slightly angled & mostly flat surface. However, the lower frequencies are more affected by the larger and deeper elements of the Model C.

How do these differences help define their use?

The Model C is a great all around diffuser – it covers a wide range of frequencies, throws a very predictable 2D diffusion pattern, and it is tuned to a very musical range.

The Model F is a great high-frequency diffuser.  It targets a few very specific, yet important issues.  High frequencies are responsible for some nasty problems in rooms.  Flutter echoes, ringing, comb filtering, and other artifacts are particularly noticeable in higher frequencies.  If your room is otherwise performing well acoustically, the Model F can help tackle that last hurdle to make a good room into a great room.

Model F and C

Many critical listening environments use both the Model C and Model F to tune the diffusion in their space.

 

While the white Aeolians® on the back wall are the visual focal-point on in Big3 Studio A, look closely at the ceiling and you will notice a large array of black Model C’s and Model F’s. These help to intermix the diffusion of different frequencies in the large control room.

Due to their aesthetic and functional compatibility, many rooms benefit from using both.  Model C’s addressing the bulk of the Mid-range diffusion, and the Model F smoothing out the top end.

I hope that this highlights the unique properties of both the ArtDiffusor® Model C & ArtDiffusor® Model F – and helps to demystify their function and use in your space.

, , ,

Leave a comment

Big3 Studios – Aeolian® Diffusers

Aeolian® Diffusers in Big3 Studios

We recently received these wonderful installation pics from our friends at Big3 Studios in Florida. They redid the back wall in one of their control rooms using our Aeolian® Sound Diffusers. In a couple of the pics you can also see our Model C & Model F Art Diffusors® (black) in the ceiling!

, , , , , ,

Leave a comment

Aeolian™ Diffuser – Mash up

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.

, , , ,

Leave a comment