Bill Malina

Bill has the technology to listen to for a month and then we moved it to another studio. This is the demo process we go through in LA. We have demo units that we rotate from engineer to engineer. They keep them for one month and then we move them to other locations. Bill went through existing sound redirection treatment on the rear wall to one-dimensional diffusion based upon prime number 13. The second demo set up consisted of two-dimensional diffusion based upon Prime 13. In the video, you can hear where Bill says that the rear wall disappears. This is the function of diffusion and especially two-dimensional diffusion on the rear wall. Where do we start with treatment?

When you are using pressure activated technology like our diaphragmatic absorption technology, you must first look to the area of highest pressure. In almost all small rooms, this area of highest pressure is between the front wall and the speakers. Bill’s room was no different and we started with our ACDA -12 module units on the front wall under the console and along the side walls. The ACDA-12 unit is more frequency specific operating from 30 – 50 Hz. This frequency range issue is found in 100 % of audio rooms regardless of the specific usage. We use a blend of ACDA – 10 and ACDA – 12 modules in all small audio rooms.

Every small room is different in the amount of energy placed into it and the amount of energy it can handle correctly. The amount and type of existing low-frequency treatment have a direct impact on all of these variables. There is a balance between the frequency specific ACDA-12 units and our broadband ACDA – 10 units. We have found that a mix of 40 % ACDA-12 units and a 60 % of ACDA-10 units work best in most small rooms where pressure levels average around 85 dB SPL. With the foam on the face of each ACDA-10 unit, you have broadband absorption from 30 – 6,500 Hz. These absorption rates and levels are designed for music and voice, not to keep your room warm or cool.

The rear wall of the room is next with a series of ACDA -12 modules as the base for the diffusers. Diffusion must be uncovered and unhindered just like a speaker. You can not have anything in between you and the diffuser. Acoustic diffusers are not active devices that produce energy through a powered source. They are purely passive devices that take reflected energy and expels it back into the room based upon the frequency response of the diffuser which is based on the distance from the diffuser to the listening position. All distance and position variables must be calculated and diligently subscribed to. You must have enough distance from the diffuser to your ears to allow for the lowest octave to fully form.