In this installment of “Similar, Yet Different”, we are going to compare the two current variations of the popular Aeolian^® Diffuser – the original 2’x2′ Aeolian and the 1’x1′ MiniAeolian™!

Design

This comparison has some similarities to the very first “Similar, Yet Different” post we made comparing the ArtDiffusor^® Model C to the ArtDiffusor^® Model F. We are looking at a diffuser that uses identical mathematic functions to create the shape… both the Aeolian^® and the MiniAeolian™ are an “Organic Quadratic” constructed from a Bicubic Interpolation of a Quadratic Residue Function. They are both truncated so that they are completely asymmetric, even to the edge. The MiniAeolian™ IS an Aeolian^®, only it is scaled differently.

You may recall that the Model F was constructed of 4 scaled down Model C diffusers in a monolithic 2’x2′ tile – This is not the case with the MiniAeolian™. The Original Aeolian^® Diffuser is a 2’x2′ footprint that is 5″ tall, and will fit in a standard 2’x2′ ceiling grid. The MiniAeolian™ is a single scaled down unit, and it is a little different – The 1’x1′ footprint stands alone as a single unit, but it is only scaled down in height to 4″.

In this case, form follows function. The MiniAeolian™ was built to fill a specific function as a smaller wall-mount unit, or a direct-mount ceiling unit for smaller spaces. Part of this wall-mount function was to have a version of the Aeolian^® that would fit in tight areas or in spaces that didn’t have enough clearance for the 5″ standard Aeolian^® (or would require modification to those areas (or diffusers) to allow this extra height). Some people implement configurations that have tighter footprint requirements, and the 1’x1′ footprint of the Mini allow it to be used in these types of layouts.

Performance

So how does this change affect the performance of the unit? Surprisingly, they are quite similar. The Organic curved design, with only a 20% reduction in height, shows only minor differences in performance of their overall frequencies ranges – with both primary ranges starting at about 1500Hz-1600Hz with and average between 150° and 170° of horizontal and vertical dispersion up to between 5Khz and 7Khz. While the primary range is a good indicator, when we look at the actual polar response, we can get a better picture of their full range performance.

A quick glance shows two very similar performing diffusers, except for the low-frequency performance. The larger elements and deeper formfactor of the original Aeolian^® are more effective at the 1000Hz range, where the MiniAeolian™ appears to be mostly specular. There are some surprises however. It appears that at the 2000Hz range leans slightly in the favor of using 4 MiniAeolians™ in an array verses the single Aeolian^®. There is more surface variation over the same footprint (2’x2′ in the array of 4), and the size of the Mini’s features are a bit more optimal for diffusing the 2Khz wavelength. This swings back slightly into the favor of the single Aeolian^® at 4Khz, where the larger elements have a wider throw, and the elements of the Mini have steeper wells. At 8Khz, it tips back to the Mini, and then at 16Khz, they are both neck-and-neck.

The amazing similarity is that the variations are quite subtle through their entire effective ranges, and even quite a bit above those ranges. While there are slight differences in the performance of the diffusers when we compare the directly, these are really very minimal except for the low-frequency edge in performance of the larger original Aeolian^®.

Closing

With the similarity of performance in the two diffusers, they can almost be used interchangeably – or even used together in the same environment to implement an aesthetic vision or add more randomness/variety to the diffusion in the space.

There are several occasions where you may require one over the other.

• If you need more 1Khz diffusion, you should add some 2’x2′ Aeolians^® – as they perform better in that range.
• If you need to install diffusers that fit in a ceiling grid… you will also want to use the original.
• If you want the Aeolian^® but need diffusers that will fit in a space that is less than 2’x2’x5″, you may want to go with the MiniAeolian™.

Currently the MiniAeolian™ is a custom order item only, and is subject to minimum order quantities.
Contact Acoustics First® for more information and pricing.