It is also nearby the Cleveland Institute of Music where RPG President Dr. Peter D'Antonio has taught for the past 10 years. Dr. D'Antonio indicated that "I have walked by this building since its creation and was intrigued with its development. When RPG learned that Dave Conant of McKay Conant Brook, Inc. specified our new absorptive plaster BASWA®phon and that FOGA enthusiastically embraced its use on the compound curved walls and ceilings of the Weatherhead School I was absolutely thrilled."

This month we begin a continuing series of informative presentations on the progress of BASWA®phon installation at Weatherhead, which is due to be finished in the beginning of 2002. RPG is working closely with GQ Contracting, Wickliffe, Ohio, a certified BASWA®phon installer. GQ has constructed a mockup of the compound curved shapes found at Weatherhead in their facility and, together with RPG, installation details for the compound curved surfaces have been developed.

RPG to exhibit at AES in New York
We invite you to visit us in Booth 803 and also visit the SONY SACD demonstration room, where RPG's Variscreens and Skylines will be in use. RPG will exhibit its full line of products and software and will introducing several new additions to the acoustical palette. Dr. D'Antonio will be at the booth to answer any questions you may have.

BASWA®phon to be showcased on This Old House
At some point or another all of us have watched This Old House.

The Emmy Award winning This Old House is television's premier home improvement series. The show that unlocked America's passion for home improvement, celebrates its 22nd anniversary season on PBS this year. This Old House's mission is to demystify the home improvement process and to celebrate the fusion of old world craftsmanship and modern technology. Each season features two renovation projects. Project One traditionally consists of eighteen or so episodes and is filmed in Massachusetts. Project Two is taped in a different region of the country to highlight the variety of American architectural styles and renovation issues. Additionally, the second project is generally located in a town with a mild climate where outdoor work can be undertaken in the winter months.

We have all enjoyed watching the staff consisting of host Steve Thomas, master carpenter Norm Abram, plumbing and heating expert Richard Trethewey and general contractor Tom Silva.

Project One this year is The Manchester House, owned by Janet and David McCue.

RPG was brought into this renovation by John Storyk of WSDG, Highland, NY who is responsible for the home theater design in the living room. The room will be used for both viewing movies and live piano recital. Storyk selected BASWA®phon to treat the existing focusing upper ceiling areas. The installation of BASWA®phon will be presented in upcoming episodes of the show, so stay tuned.

Dr. D'Antonio to address NCAC at ASA meeting in Ft. Lauderdale

Dr. D'Antonio, President of RPG, is honored to be invited to present a 2 hour lecture at the NCAC General Membership Meeting and Seminar at the NCAC meeting in Ft. Lauderdale on Monday December 3rd, 2001 from 9 AM - 12 Noon in Room 122-123. The topic will be "Expanding the Acoustical Palette: New Absorptive and Diffusive Surface Treatmenets and Pending Diffusion Standards".

Dr. D'Antonio will describe several new acoustic tools available in architectural acoustics, namely the binary amplitude diffsorber, shape optimized surfaces, new smooth and monolithic absorptive plasters, new absorptive wood systems, new absorptive glass, and new passive and active variable acoustics systems. He will also review the development of the diffusion coefficient and the scattering coefficient and how diffuse reflections can be incorporated in room acoustic modeling programs with examples in CATT Acoustic. We hope all of the NCAC members will be on hand.

We also invite all NCAC members to join RPG at the NCAC Reception and Tabletop Exhibits from 6-8 PM on Sunday December 2, 2001 in the Atlantic Ballroom I & II.

RPG publishes absorption data for BAD™ Panels in various thicknesses
The BAD™ panel has transformed RPG's flat upholstered panel business. The BAD™ is the first flat panel that offers diffusion above 1000 Hz and absorption below. It is now being used either as a replacement for absorptive panels or in conjunction with them. RPG® now offers both purely absorptive and diffsorptive panels. The largest markets are in worship spaces, corporate facilities, schools, home theaters, and recording studios. The BAD™ panel provides reflection control above 1000 Hz using diffusion, instead of absorption. The result is reflection control with accompanying ambiance. The template membrane construction also offers better absorption below 1000 Hz compared to standard absorptive fabric wrapped panels. RPG is currently supplying the BAD™ panel in thicknesses of 1", 2", 3" and 4" and the accompanying absorption data are now available.

Reverberation time, diffuse reflection, Sabine, and computerized prediction - part I
RPG offers a tutorial to explain the effect of diffuse reflections on reverberation. RPG is frequently asked what the effect diffuse reflections have on reverberation time. Since acousticians are used to using Sabine, Eyring, Fitzroy and Arau-Puchades to calculate reverberation time using absorption coefficients, it is natural to ask if there is an equation that can incorporate diffusion. The short answer is that all of the above mentioned equations already assume a totally diffuse sound field, so the real question is "How does one calculate reverberation time correctly when the sound field is not diffuse or mixing?". One answer to this lies in the use of computer prediction programs, which properly take into account diffusion. One of the initial findings of round robin experiments comparing experimental measurements with computer predictions was the absolute need to include diffuse reflections. Today, diffuse reflections are attempting to be modeled in commercial programs. CATT Acoustics has been on the forefront in diffusion modeling and so we have asked the creator of CATT Acoustics, Bengt-Inge Dalenback, to write a tutorial that we will run in two parts on our website. RPG has been doing its part to experimentally measure and theoretically predict the diffusion coefficient and there have been significant advances in the creation of a method to measure the random incidence diffusion coefficient, specifically to be used by the computer modeling programs. Therefore, with these data close at hand, I encourage all acousticians to read this tutorial to advance the accuracy of the computer prediction of reverberation time and the other objective parameters.

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Dr. D'Antonio publishes continuing series on new architectural acoustical tools in Archi-Tech magazine.
Welcome to ARCHI-TECH. Subtitled, "Bridging the Gap Between Design & Technology." This magazine has been created specifically for architects, systems designers and integrators for commercial and residential buildings. The purpose is to provide critical information surrounding the all-important business of integrating technology into building design and architecture. With an emphasis on commercial and residential buildings, the editorial purpose is to inform, educate and help establish a comfort level among architects with systems integration. Each issue provides cutting-edge feature stories, state-of-the-art product and industry information, news, trends, advice and success stories in the areas surrounding commercial and residential building design and technology.

The first installment of Dr. D'Antonio's serialized contribution appears in the Residential issue September 2001 issue, Volume 4, No. 5 entitled New Acoustics: Sound Diffusors. in the new ArchiTech Residential. Subsequent articles will cover New Optimized Surfaces, New Absorptive Materials, Desktop Auralization.

RPG add reverberation chamber and impedance tube measurement capabilities at headquarters

RPG adds absorption measurement capabilities down to 10 Hz to its diffusion measurement capabilities With the publication of the AES-4id-2001, the acoustical community is now aware of the various measurement goniometers RPG has developed and the many years of research that have gone into creating a measure of scattering. Acousticians can now utilize this diffusion coefficient to evaluate potential diffusing surfaces. RPG also uses the diffusion coefficient in our Shape Optimizer, which combines an architectural motif with desired scattering performance, to create custom shapes for performance facilities. Please consult our website for more information.

RPG is also very much involved in bringing innovative absorptive and diffsorptive products to the acoustical community. These products include our new absorptive plaster called BASWA®phon, absorptive Topakustiks® and Topperfo® wood systems, diffsorptive slotted FlutterFree® (described in Diffuse Applications) and the binary amplitude diffsorber (BAD™ panel). To assist in the development and testing of these new absorptive and diffsorptive products, RPG has recently added a reverberation chamber, several impedance tubes providing absorption coefficients from 10 - 5000 Hz and a flow resistance apparatus to complement its diffusion testing goniometers.

The reverberation room measures 10' x 14' x 19', which is capable of providing good statistical absorption coefficients down to roughly 200 Hz. To extend our capability to measure absorption coefficients down to 10 Hz, we have also added a 7 ton, 2'x2'x24' impedance tube using the two-microphone method according to ISO 10534-2 and ASTM E1050-90. This new impedance tube gives us the capability to document the performance of materials in the sub-100 Hz region, not accessible currently using the reverberation room method. This information is sorely needed in recording studios and home theaters, where subwoofers are routinely used. We are also developing additional impedance tubes to study small homogeneous samples over the rest of the audio spectrum. This approach will be used to study and continually develop BASWA®phon. Since we get so many questions on the applicability of various fabrics to cover our BAD™ panels and diffusive products, we will also be adding a flow resistance tube to quantify fabric performance.

We invite the acoustical community to visit us for our Diffuse Seminars and use these facilities for research.