PROUDFOOT ARCHITECTURAL ACOUSTICS
The Proudfoot Company, Inc. is an industry leader in acoustical correction and noise control. Since 1965, Proudfoot has worked with architects and engineers to control noise levels on a wide variety of projects through incorporation of its SOUNDBLOX products. lens of millions of these popular units are in place around the world today.

AN INTRODUCTION TO SOUNDBLOX
SOUNDBLOX units are the solution to acoustical correction and noise control problems in masonry construction. Attractive, economical, and efficient sound absorbing units, SOUNDBLOX are made locally near the jobsite by carefully selected quality concrete block producers. These producers employ patented Proudfoot molds designed to fit standard automatic block machines thereby assuring uniform quality and acoustical efficiency of each SOUNDBLOX unit.

SOUNDBLOX MASONRY UNITS ARE STRUCTURAL  LOAD-AND-BEARING
SOUNDBLOX have the same compressive strength as standard hollow concrete masonry units of similar composition. Installed conventionally with little or no added labor, the in-place cost of SOUNDBLOX is low by comparison to most other acoustical materials. Hugged and durable in construction, SOUNDBLOX masonry units are an excellent choice for industrial settings, gymnasiums, mechanical equipment rooms, and comparable installations.

A CLOSER LOOK AT SOUNDBLOX
SOUNDBLOX derive their excellent sound absorption from a unique cavity-slot resonator construction. The cavities are closed at the top and the slots allow the cavities to function as damped (Helmholtz) resonators an excellent sound absorption tool allow frequencies. The slots of the H, HSR, RSC and 0 Type units are funnel-shaped for superior acoustical performance. The amount of sound absorbed by properly installed SOUNDBLOX is increased dramatically when units incorporating a metal septum (membrane or divider) and fibrous filler in the cavity are specified. Together with funnel-shaped slots, these units provide higher levels of sound absorption across a wider range of frequencies. In addition to sound absorption, SOUNDBLOX walls have a superior sound transmission loss (STL) performance rating when compared to walls of ordinary hollow concrete blocks of similar composition.

Economy is another characteristic of the SOUNDBLOX line. Costly long- distance shipping of SOUNDBLOX is never required as units are manufactured around the world, and therefore local to most any job site. And SOUNDBLOX are fire rated for up to three plus hours.

Most concrete masonry appearance options are available for SOUNDBLOX including colors, ground face and scoring. Refer to your local representative for more information. The Cavity-Slot Resonator Construction of SOUNDBLOX masonry units employs the same resonator principle of sound absorption as that used in automobile mufflers. In effect, the specially designed metal septa, which reflect the higher frequencies but transmit the lower frequencies, provide two resonators in each block cavity where only one existed before. Tuned to different frequencies an octave or more apart, the dual resonators greatly widen the frequency band where very high sound absorption is obtained. This high level of absorption has been extended even further in the new Type RSC units by the use of sequential cavities molded right into the blocks.

All SOUNDBLOX masonry units incorporating the septum are produced with the flared, funnel-shaped slot which accommodates superior acoustical coupling to the resonator cavities. Many units also use incombustible fibrous fillers which increase sound absorption capabilities at higher frequencies.

SPECIFICATIONS

Scope: Sound absorptive concrete masonry units shall be used to construct exterior and interior walls or partitions as shown on the plans and/or indicated in the Schedule of Finishes.

Material: All sound absorptive masonry units shall be SOUNDBLOX made on standard block machines using molds furnished or approved by The Proudfoot Company, Inc., Monroe, Connecticut. They shall be made of carefully prepared aggregate and shall meet the current ASTM C-90 or ASTM C-129 requirements as appropriate. Carefully controlled use of the SOUNDBLOX molds shall be employed so all units have one end of the cavities tightly closed. Slots and edges shall be straight and clean. Where Types H, Q, RSC, HF or RSH SOUNDBLOX units are called for, filler elements as supplied by The Proudfoot Company, Inc., shall be installed in the cavities of the blocks at the block plant. The fillers shall be of specially fabricated incombustible fibrous material, cut accurately to size and installed as recommended. The fillers shall have metal septa laminated to one side of the fibrous material and shall be installed with the septa facing away from the slots. Where 8" Type o units are called for, they shall have a bare (without fibrous material) metal septum as furnished by The Proudfoot Company, Inc., installed in each cavity in the recommended manner at the block plant.

Sizes and Types: SOUNDBLOX units shall be 8" x 6" nominal face size. They shall be of the thickness (4', 6", 8", 10" or 12") and Type (A-i, H, RSH, RSC, HF or Q) as shown on the plans and/or indicated in the Schedule of Finishes.

Installation: SOUNDBLOX units shall be installed by the General Contractor (or Masonry Contractor) using only mechanics skilled in the laying of masonry blocks. All necessary cutting on the job site shall be performed with power tools in such a manner as to provide straight and true edges. No chipped or broken blocks shall be used. SOUNDBLOX units shall be laid in running bond (or stack bond) with the open ends of the cavities facing downward, and shall be seated in a full horizontal bed of mortar. The slots shall be exposed to the area where the sound absorption is desired as indicated on the plans. Care shall be taken to ensure that the slots are kept free of mortar or debris above the mortar joints. Lines shall be straight and true and the SOUNDBLOX workmanship shall otherwise conform to all requirements of the General Specifications for masonry work.

Painting: SOUNDBLOX units may be painted without significant reduction of sound absorption from the values shown which were determined after the faces had already been painted. Lightweight SOUNDBLOX units have substantially more sound absorption when unpainted but — except for split-rib units — few units are ever left unpainted. Walls of SOUNDBLOX units made of lightweight, porous aggregates must be heavily painted with cement base or other sealing type paint on the unslotted side to prevent porous sound transmission where maximum sound transmission loss is desired. Such painting is also required on ordinary hollow concrete masonry units of lightweight, porous aggregates to prevent porous sound transmission.

Fire Endurance: Fire testing in accordance with ASTM E-1 19 requirements show fire endurance ratings of up to 3 hours plus for load-bearing walls built of SOUNDBLOX units. Specific details are available upon request.

Code Acceptance: SOUNDBLOX units are approved for use in reinforced masonry construction wherever ordinary hollow concrete masonry units are permitted. This applies to seismic zones as defined under the Uniform Building Code, with 90% of the shear value of ordinary hollow concrete masonry units allowed for the SOUNDBLOX units. (See City of Los Angeles Dept. of Building and Safety Research Report No. HH23609.)