Excellent insulation + Excellent adhesive force

I bought a new computer case, Fractal Design OEM PCGH-CA-DEF-R4 ATX Midi Define R4 PC case, a Silent housing it should be, according to the description. In reality, however, only 3 anti-drone mat were glued one on the two sides and the top of the housing. Who has studied sound propagation and sound, who knows that anti-drone matting only insulate structure-borne noise. The airborne sound, caused by the fan, is characterized not insulated.
This here present acoustic foam with 30 micron thick polyurethane film insulates the airborne sound excellent. The tear-resistant and easy to clean surface of the PUR film looks like leather.

I've pasted both the already glued with an anti-drone mat surfaces and all exposed metal surfaces of the computer case, and then were the Silent fans even with max. Speed, no longer be heard. Now I have an absolute Silent computer.
For a mid-tower computer case only 1 m² is needed - it would therefore have sufficed: acoustic foam with foil selfadhesive !!! 50x50x1cm 4 pieces Non-combustible P154

The acoustic foam can be cut easily with a sharp utility knife and a steel rail to a cut-resistant plate (best hard tissue, laminated paper, PVC or chipboard). The adhesive strength is excellent, in contact with the ground all bonded immediately, corrections are almost impossible, therefore, to work carefully and measure everything carefully beforehand.

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