Spectra-Glaze® Block

Spectra-Glaze® Block Soundblox® Series Web Page

Most Frequently Asked Questions:
Cost:
Spectra-Glaze® / Soundblox® Block are approximately $14.10 per square completely installed. This cost is an average of all licensed manufacturers in the United States and Canada.

How can I get in contact with The Proudfoot Company, Inc.?
Soundblox® trademark licensed in the US is exclusive property of The Proudfoot Company, Inc., who can be reached at P.O. Box 276, Monroe, CT 06468-0276, Telephone Number 203-459-0031, Fax Phone Number 203-459-0033, 800-445-0034 Toll Free.
Information concerning Soundblox® uses with other applications are available.

What through wall sizes are available?
Spectra-Glaze® Soundblox® Block are 8x16 nominal face size. Although many types of Soundblox® are available, Spectra-Glaze® Soundblox are typically made with Type, R, RSC, RSR or RF slot and core configurations. Some manufacturers will produce a Type A-1 or Q Block. Through wall size are available in 4", 6", 8" and 12" block sizes.

What type of fire rating can I get with Spectra-Glaze® Soundblox® Block?
Fire testing in accordance with ASTM E-119 requirements show the fire endurance ratings of up to 3 hours plus for load bearing walls built of Soundblox® Block. Specific details are available upon request.

How do Soundblox® Block work?
When sound is generated, air is set into motion in a wave pattern. High frequency sounds have a short wave lengths and low frequency sounds have long wave lengths. A sound wave in the air at 125 Hz has a wave length of over 8 feet. When sound waves reach a Soundblox® block, the air inside the cavity created by the closed top of the unit acts like a spring while the air in the slot is forced to oscillate in and out of the cavity. The friction of this motion dissipates the sound energy and we have sound absorption. These types of absorbers, called resonant or resonator absorbers frequency. The absorption coefficients of the Type A-1 units reflect this peak characteristic most particulary. The sound absorption can be broadened to cover a wider frequency range by the addition of porous absorptive materials in the cavity and by acoustically dividing the cavity, The absorption coefficients of the Type R, RR, RSC or RSR units reflect this broader absorption characteristics. The slot/cavity design of Soundblox® units coupled with the fibrous fillers and setpa function together in providing their excellent sound absorption performance.

Are Soundblox® Blocks load bearing?
Yes. Providing they are made of the same aggregate necessary to produce load-bearing regular units. And, since they are load bearing, noise control can be built right into the structure of a building. Also, Soundblox® units have been allowed 90% of the shear value of ordinary hollow concrete masonry units of the same thickness.

Can Spectra-Glaze® Soundblox® be used outdoors?
Yes. Millions of Spectra-Glaze® and Soundblox® Blocks have been used for transformer and other types of outdoor noise screens and for highway noise barriers. For outdoor use, the NEED TO FINISH

How much noise reduction can I achieve using Spectra-Glaze® Soundblox® Block?
The maximum practical reduction in sound level that can be achieved using sound absorption alone is 10 decibels and generally the achieved reduction may be more like 6 to 8 decibels. However, most people perceive a drop of 10 decibels as resulting in a noise only half as loud so even 6 to 8 decibels can be well worthwhile in providing increased comfort.

How many Spectra-Glaze® Soundblox® Block should I use?
Although there are formulas to calculate how many blocks should be used to achieve a certain amount of absorption, for gymnasiums and auditoriums and swimming pools, etc. where understanding speech is critical, it is best to use the service of an acoustical consultant. Where the problem is not too complex, we can often be of help. A rule of thumb for mechanical equipment rooms and noisy manufacturing areas is to construct a wall area equal to 30% to 40% of the total area of walls, floor and ceiling with Soudblox® units, if this amount of the area is available. Note that as a room becomes larger by increasing the length and width while keeping the ceiling height constant, the wall area becomes a smaller part of the walls of Soundblox® units may not be sufficient. Some ceiling treatment should be used as well.

Which type and thickness of Spectra-Glaze® Soundblox® Block shall I use?
By far, the best way to select the most efficient unit for the job is to obtain, by measurement, a frequency characteristic of the noise from the source. If high sound levels are distributed over a wide frequency range, a Type R, RR, or RSC unit would be a good choice since these units have excellent absorption at nearly all frequencies. If the noise level measurements indicate a pronounced peak at specific frequency the unit with the highest sound absorption coefficient at that frequency is usually the best choice, e.g. for a noise with a high peak at 125 Hz, the 8"Q units would be a good choice since it has excellent absorption at 125 Hz. If the noise is concentrated at the very low frequencies (below about 500 Hertz) the Type A-1, R, or RSC units can often be used to advantage.

Can Spectra-Glaze® Soundblox® Block be steam cleaned?
Since Spectra-Glaze® Block uses the Soundblox® Type R or RSC, it is generally not recommended to be used in areas which are to be hosed or steamed cleaned. However, Type A-1 and Type Q Soundblox® can be hosed down with water or steamed clean and some licensed Spectra-Glaze® manufacturers will glaze a Type A-1 or Type Q Soundblox® Block.

What does STL mean?
STL stands for Sound Transmission Loss. While sound absorption is a measure of how much sound is absorbed by a given material in a room, sound transmission loss os a measure of how much sound is transmitted from one room to another trough a partition constructed of the test material. Even though Soundblox® units have slots in one face shell, they nevertheless have somewhat better sound transmission loss than ordinary hollow concrete masonry units of the same thickness and composition because of other acoustical effects of the resonator mechanism. Although the primary function of Soundblox® is sound absorption, they can also be relied upon to do an excellent job of keeping noise in one room from being transmitted to another through the Soundblox® wall itself. The STL, or Sound Transmission Class, is "one number" measure of the overall efficiency of a barrier.

What does NRC mean?
NRC stands for Noise Reduction Coefficient. An NRC rating is a number which is the arithmetic average of the sound absorption coefficients at four frequencies: 250, 500, 1000 and 2000 Hertz taken to the nearest .05. Generally speaking, the higher the NRC, the more absorptive the material is. However, since the NRC is simply an average and includes only the middle four frequencies, its practical use is limited. For example, if one has a noise problem concentrated near 125 Hz (such as transformer noise), trying to select the best sound absorptive material on the basis of its NRC do not included the value obtained at 125 Hz. In that case, attention should be directed to the sound absorption values at individual frequencies.

Patent pending. Design, physical appearance and pattern are copyright and trademark property of
Southeast Capital Corporation, licensed users and master licensors are Spectra Development Corp.
and Spectra Industries, Inc. All rights reserved. Registered or Trademarks are property of
Southeast Capital Corporation in United States and foreign countries.