Audio Engineering

Room Acoustics 851

Triple layer constructions and multiple layer heavy masonry constructions can be
employed to achieve improved levels of insulation, particularly at the lower frequencies.

Studios can also be built from modular construction assemblies based on steel panels/
cavities lined with sound-absorptive material.

The following table compares a double leaf steel panel construction with an equivalent
thickness (300 mm) of masonry wall construction.

Frequency (Hz) 63 125 250 500 IK 2K 4K

Masonry 28 34 34 40 56 73 76

Steel paneling 40 50 62 71 80 83 88

Again it must be remembered that when it comes to sound insulation, large differences
frequently occur between the theoretical value (i.e., what can be achieved) and the actual

Structural coiling

75 50 mm

Softwood

studding

100 50 mm

12.5 mm

Plasterboard

12.5 mm

Softboard

Skin coat

of plaster

Skirting

50 mm

Airspace

Skim

plaster

coat

Mastic

Carpet Felt

Felt

Figure 29.4 : Typical construction of a double-skin lightweight compartment.