In this article we wanted to compare how Producer’s choice acoustic blankets compare to Fiberglass insulation in its sound absorption property and also in ease of use and convenience.
We tried to be as accurate as possible, but since the comparable fiberglass products for acoustical use is different from Acoustic Blankets in its form , thickness and application, it was somewhat difficult to make direct apple to apple comparison. Certain assumption had to be made in the conclusion to compare the results.
Both Acoustic Blankets and Fiberglass wool are porous absorbers. Once the sound gets inside the absorber Sound energy is spent on vibrating the fibers of the material and converts into heat.
Therefore it is important that the outer fabric is porous enough for the sound to get in.
Acoustic Blankets producer’s choice.
Outer fabric – Cotton/Polyester mix 70/30. GSM 80.
Inside filler: recycled cotton.
Thickness approximately 1/2 inch (not pressed).
Weight: 8.5 lbs per 40 s.f. 0.2 lbs per square foot/
Noise reduction Coefficient (G-75 mount)
Hang in Straight layer ==> NRC 0.80
Hang as Pleated curtain ==> NRC 0.95
( see actual test results attached)
NOTE: in both tests we used the same blanket, but ion the test results marked “PLEATED” the allowed the blanket to form natural folds like curtain (pleats approximately 4-6 inch deep)
|VB72 Producer’s Choice Blanket.
|1/2 inch||0.2 pcf (3.2 kg/m3)||G-75||0.13||0.44||0.86||0.97||0.92||1.02||0.80|
|VB72 Producer’s Choice Blanket.
|0.36 pcf (3.6 kg/m3)||G-75||0.39||0.84||0.90||0.96||1.02||1.12||0.95|
(The closest match we could find is Owens Corning’s Select Sound Black Blanket)
Owens Corning Fiberglass Blankets:
|SelectSound Black 150B Blanket||1″ (25mm)||1.5 pcf (24 kg/m3)||0.10||0.34||0.64||0.87||0.91||0.91||0.70|
|Thicker Blanket||2″ (51mm)||0.27||0.80||1.12||1.07||1.02||1.01||1.00|
In the chart below we combined the results i n the two tables above.
As the graph shows, the Producer’s choice blankets performed better acoustically than Fiberglass blanket twice as thick. (NRC of 0.80 for 0.5 inch thick Producer’s choice acoustic blanket compare to NRC 0.70 for 1 inch Fiberglass SelectSound Blanket.)
From the same graph it is interesting to note that the same blankets used in pleated fashion performed very close to Fiberglass blanket that was 4 times thicker ( 2 inch thick fiberglass blanket, compared to 1/2 inch pleated Producer’s choice blanket). And costs nearly 10 times more!
It is safe to assume that doubling the thickness of the blanket (by using two blankets for example) would effectively outperform 2 inch fiberglass blanket.
Interesting to note that Producer’s choice blankets actually outperformed 2″ fiberglass blankets at the lower and higher range frequencies, where Fiberglass showed a spike in midrange. The more leveled broadband sound absorption of Producer’s choice blankets results in acoustically better sounding recording, than Fiberglass blankets, which rips out the midrange frequencies potentially creating boominess of the sound.
Cost: Fiberglass sound absorption blankets 2″ thick can cost around $190 for 32 s.f. blanket, which is $5.94 per square foot. Producer’s choice blanket is around $25 for 40 s.f. or $0.63 per square foot.
It is important to understand the health risks associated with exposure to fiberglass insulation. When it is disturbed, fiberglass insulation releases particulates into the air which may be inhaled Small particles that come into contact with skin can lodge in pores and cause itchiness, rashes and irritation. When inhaled, particles can cause coughing, nosebleeds, and other respiratory ailments. Very fine airborne particles are capable of becoming deeply lodged in the lungs and are believed by many to cause cancer and other serious afflictions. OSHA considers this threat to be serious enough that it requires fiberglass insulation to carry a cancer warning label.
To keep fiberglass particles from becoming airborne fiberglass material have to be enclosed in a dense outer fabric. Which is counterproductive from the sound absorption point of view, since dense fabric is more reflective.
Cotton fibers do not have such harmful properties. Producer’s choice blankets are made with natural cotton fibers, with extended length of fibers to reduce dust
In Conclusion: Test data prove that Producer’s Choice Acoustic Blankets are more efficient that Fiberglass blankets of similar density. The Sound Absorption curve is more leveled which results in better sound quality. Producer’s choice Blankets have no hazardous properties of fiberglass. Besides being more efficient Producer’s choice acoustic blankets are more economical solution compare to fiberglass blankets.
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