The panels’ rear and side surfaces are flat, while the fronts of the panels feature a geometric grid array of posts and wells (196 of them per panel) of varying heights and depths. The exact height and depth dimensions of the posts and wells are dictated by a so-called “primitive root” numeric sequence that in essence helps maximise the range of audio frequencies over which the panel provides meaningful diffusion. What is more, the faces of the posts and wells are deliberately angled, which also helps improve diffusion characteristics.
The primary purpose of the panels is, of course, to provide two-dimensional (that is, “hemispheric”) broadband diffusion and a performance chart for the DC2 panels shows that indeed their diffusion coefficient remains remarkably consistent from 125Hz (coefficient = .67) on up to 5kHz (coefficient = .75) and beyond. However, the panels do also provide a modest degree of absorption, with their absorption coefficient becoming most effective from about 800Hz to 2kHz and then gradually tapering off from 2kHz to 5kHZ. Importantly, and unlike many of the so-called quadratic-residue diffusors on the market, the performance characteristics of the DC2 panels are the same in the vertical and horizontal axes.
How do the Multifuser DC2 panels work in practice? In my room they worked like a charm, transforming a space that initially seemed an acoustic ‘problem child’ into what frankly has become the nicest sounding listening room I have ever had. For my application, I used a total of twelve DC2 panels arranged as four columns of three panels each—two on the rear walls of the room and two on the sidewalls (positioned at the first reflection points). The results were impressive to a downright jaw-dropping extent.
First, the characteristic midrange and upper midrange brightness of the room was corrected, yet with no apparent loss of musical energy or information in either frequency band. Second, imaging became more continuous, meaning there was little if any tendency for there to be a sonic ‘hole in the middle’ between the speakers, while perceived imaging focus and specificity were dramatically improved. In layman’s terms, the diffusors seemed to take the room out of the equation, so that I could more clearly hear what the loudspeakers were doing. Third, spatial cues in the music, including very subtle recorded echoes and reverberations, became much easier to hear, as did sounds of instruments and voices interacting with the acoustics of various recording venues. The upshot was an increase in overall soundstage size and three-dimensionality. Finally, the panels worked equally well with dipole and with forward-firing loudspeakers. When you put all of these virtues and benefits together, the Vicoustics panels seemed like nothing less than acoustical miracle workers.
How are the Vicoustics panels mounted in one’s room? The answer is that in many applications the panels would be affixed to wall or ceiling surfaces using special flex glue that Vicoustics makes for this purpose. At the same time, though, I should point out that the panels don’t have to be attached to walls at all to be effective. In my case, for example, I found it perfectly acceptable to place panels on the floor, butted up against the wall, and then to stack additional panels on top. The beauty of this approach is that you can experiment with different panel placements as you wish without having any glue residue to clean up.
Saving the best for last, let me mention that the Vicoustics Multifuser DC2 panels aren’t expensive: many UK retailers offer them for £339 per six-pack box, while US retailers typically sell them for $649 per box. Either way, the value for money on offer is clear off the charts. Vicoustic says the DC2 is “the best cost/performance diffuser money can buy,” and until I discover something better for less, I would enthusiastically concur.
Type: Two -dimensional (“hemispheric”), Primitive Root sequence-based acoustic diffusor panel.
Construction: EPS (expanded polystyrene)
Dimensions (H×W×D): 570 ×570 ×177mm
(23.6 ×23.6 ×5.5 inches)
Price: £339 or $649 US/box of six
MANUFACTURER INFORMATION: Vicoustic SA
Distributor Information (UK): Source Distribution
Tel: +44 (0)20 896 250 80
Distributor Information (North America):
Audio Plus Services
Tel: +1 (800) 663-9352