February 1, 2002

Vancouver BC: Primacoustic Razorblade Diffusor.

Primacoustic RazorBlade Quadratic Diffuser

Port Coquitlam, BC Canada - Primacoustic, (The acoustical division of J.P. CableTek Electronics Ltd) is pleased to introduce the RazorBlade broadband quadratic diffuser.

The RazorBlade is designed to control primary reflections and reduce standing waves by scattering acoustic energy while retaining a more natural ambient sound over absorptive panels. The result is a sense of greater space and openness, while expanding the 'sweet-spot' in the control room.

According to company president, Peter Janis: "Our goal in developing the RazorBlade was to provide full bandwidth diffusion yet be affordable. Unfortunately, there is no shortcut to this dichotomy: To diffuse bass, because of the longer more powerful wavelengths, you need depth for ¼ wavelength calculations and one must introduce sufficient mass and stiffness so that the energy does not pass right through or set the diffuser into vibration. Lightweight polystyrene or plastic diffusers are only effective in the upper strata but do nothing in the bass. This is why speaker cabinets are built out of high-density wood and we employ multiple layers of sheetrock when building studio walls. Furthermore, to achieve smooth high-frequency diffusion, the design must integrate many slats in order to properly address the smaller wavelengths."

Janis continues: "Bigger, deeper, with more slats unfortunately equates to a higher cost from the outset. This meant that we had to find a way to shave manufacturing costs in order to hit our desired price target. We figured that if we could automate the process by using numerically controlled routers and saws, and build enough of them to take advantage of the volume savings, we could produce a high performance product that was not only better than anything on the market, but was also sufficiently affordable that this type of diffusion technology could gain general appeal. The response has been nothing less than overwhelming!"

The RazorBlade is a true quadratic diffuser whereby a precise series of different wells are spread across a wall plane and mathematically calculated to break-up and scatter acoustic energy at all frequencies within a given bandwidth. Effective from 350Hz to 10kHz, the RazorBlade features sixteen wells of solid MDF construction for maximum density and deflection at all frequencies. All slats feature 'dado, dowel and glue' construction for maximum stiffness, while eliminating any chance for rattle or self-noise.

Although primarily intended for studio control rooms, the RazorBlade may be used in all construction including soft-seat theaters, auditoriums, home-theater, in fact any room that requires acoustical control of the ambiance.

Normally, the RazorBlade is mounted at the 'receive' end of a room, behind the engineer whereby direct energy from the speakers is scattered in a random fashion. Space permitting, the RazorBlade may also be used on the ceiling or on sidewalls for greater control. Used in conjunction with Primacoustic foam, The RazorBlade provides a complete acoustical solution for any room.

The RazorBlade measures 24" wide, 48" high, and is 8" deep, and is available in choice of black or primer coat for painting. For more information contact Primacoustic, #114\-1585 Broadway, Port Coquitlam, BC V3C 2M7 Tel; (604) 942-1001 Fax; (604) 942-1010 or visit .


Why is the RazorBlade 8" deep?
All frequencies have a given wavelength and these all have a given size. Using quarter wavelength calculations, 8" of depth will diffuse a 32" wavelength or 410Hz. Due to the angle of incidence, and acoustic by-products such as 'lensing', we can often achieve a further doubling of the low frequency performance and reach down to 205Hz. To be safe, we specify the RazorBlade to be effective to approximately 350Hz.

I heard only high frequencies were directional?
The higher the frequency, the shorter the wavelength, the more directional they become. This is why in PA systems we use wave-guides or horns to direct high frequencies. Conversely, bass is omni-directional and is why sub woofers can be placed just about anywhere in a room. The lower the frequency, the more difficult it is for the ear to localize. Diffusers like the RazorBlade are designed to help us manage directional frequencies, which generally begin in the 300Hz region.

Why is the RazorBlade so heavy?
To absorb energy, you need a soft, porous substance like acoustical foam or fiberglass. To reflect energy, you need a hard and extremely rigid material like wood or concrete. To stop sound, you need mass like sand or lead so that the energy does not pass through. To reflect energy, the device must hard, dense and heavy or it will have not appreciable effect.

Why is the RazorBlade made with different well depths?
A sound entering the wells will enter at a given moment in time. The different well depths are calculated and spread in such a way as to delay the energy as the sound is reflected back into the room. Deeper depths allow lower frequencies with longer wavelengths to be broken up while more separations or slats are needed to affect the higher frequencies.

Can the RazorBlade be painted?
The RazorBlade is available in two finishes: Black for those that simply want to buy the unit and put it on a wall and off-white primed for painting. This allows the studio designer to match a color for room décor.

Can I order a custom color or finish or maybe a special wood?
No, not at this time. In order to get the cost down, we have to mass-produce the RazorBlade. This unfortunately limits the selection.

Can the RazorBlade be mounted on its side?
Yes. The RazorBlade is designed for the wells to be positioned in either the horizontal or vertical plane. Most studio control rooms are wider than they are high. This advantages the placement with the slots in a vertical position whereby the energy will be scattered across the room as opposed to up and down.

How many RazorBlades do you need in a given room?
Using vector calculations, one normally will extend at least the width of the console at above the 32" mark. On a typical 8ft wall, this leaves 16" to the ceiling, which is often coated with absorptive materials. In larger, wider rooms, one will try to treat about 75% of the width with diffusion, centered behind the engineer.

Why do most project studios only use acoustical foam for treatment?
Price. Up until now, the only viable option available was either very expensive or simply was ineffective. RazorBlade is in fact arguable better than any other commercially available diffuser and is extremely affordable. At $250US, one can easily afford to invest $750 to $1000 into a room to get real diffusion.

Is the RazorBlade available at any music store?
No. RazorBlade is only available at authorized Primacoustic shops. These tend to be the high-end professional stores where the staff is educated and can assist the client in making the right decision.

For more information, please contact Primacoustic #114-1585 Broadway, Port Coquitlam, BC V3C 2M7. Tel: 604-942-1001 Fax 604-942-1010

Visit for press releases and downloadable image sets.

(click image to view larger)
D/L - Hi-Rez image set (1.6MB)
(click image to view larger)
D/L - Hi-Rez image set (1.6MB)

Product Lines | News | Reviews | Ordering | Contact Us | Radial |

2000 CableTek Electronics Ltd.
1638 Kebet Way - Bldg 100, PortCoquitlam, BC V3C 5W9
Toll Free: 1.800.939.1001 | Tel: 604.942.1001 | Fax: 604.942.1010