* Insulation that may come in the form of fiberglass, paper fiber or foam which can be availed of from a professional insulation company.
* Manufactured wall coverings especially made for soundproofing can be bought at drywall supply houses, home improvement warehouses, or lumberyards.

After having your soundproofing material in place, you can then hang the drywall.

A straightforward wooden construction is not a good sound container. The average attenuation will be less than 10dB.

If one considers an average music level of 107dBA, at 1m in front of the speakers, then the expected level just outside the room will be around 90-95dBA.

Nuisance noise level is generally defined as anything over 65dBA.

Assume that, at 20m from the room, in open air, the noise measured music level will be in the order of 6dBA below that directly outside the room. At 40m the level will reduce by 6dB and successively another 6dB with each doubling of distance.

This means that, without some extra soundproofing, at maximum safe output, the levels will be causing nuisance at around 150m radius.

A double skinned room will see the nuisance radius reduced to about 20m. It may be further reduced to around 5m by lagging the insides of the walls with heavy drapes (like that compressed cotton waste matting).

If I were designing a stand-alone music room, I’d build a Cinder Block enclosure, lagged with compressed fibre glass matting ( say 100mm thick. The internal wall would best be soft fibre board. The floor, probably made up from MDF attic flooring, should be isolated from the internal walls and mounted on dense foam. The separation would typically be around 10mm and filled with silicon filler, or builder’s foam filler.

To achieve optimum internal resonance, I would construct a set of 1m sq. shallow pyramids, say about 100-150mm deep; from heavy duty cardboard……. the sort used for bankers boxes. Mounted about 200mm apart, around the wall (peaks facing in) and given a good coat of smoothed textured paint, finished with gloss.

Carpet the floor with a wall-to-wall piece of carpet (any old piece will do) with a good thick underlay and the room is ready for equipment.

OH! Any windows to be double glazed and the door to be either mounted in a lean-to porch, or screened with a fibre-board screen, equipped with reflective pyramids. Consider heavy drapes at each corner of the room……… both decorative and echo-absorbent.

Mount all speakers on cushioned pedestals, around 150-300mm from walls.

Of course all this can be avoided, if you use multimedia chairs, wired up to the music source! (£75.00-ish from PC World!) This is what my daughters bought for our front room! Maw and I enjoy out TV, while the rest fry their brains!……… and the only disturbance are our mad hamsters!

rofl