Acoustics
Sound is sneekier than water !
Studio roofs have to be fully sealed against the walls and very heavy (as heavy as the walls!) Floors will transmit sound – both ways; they may have to be semi floated at least. Many are fully floated on variable compression neoprene blocks.
Doors and windows are the weak points – we manufacture acoustic door sets with magnetic seals, each set is circa 100kg (weight again) If possible an acoustic lock should be designed in, doors can drop circa 38dB provided they are built well and fully sealed against air, that is usually not enough against an outer area alone.
Isolation or “Dropping sound” how we express it.
So what is this dB(A) thing?
Bear in mind that roughly speaking each 10dB(A) increase in sound level is perceived as a doubling of subjective loudness by the human ear. So a jackhammer would be perceived as 16 times louder than a car on a motorway that is a 40dB(A) increase.
0-10dB(A) – Threshold of hearing depending on age etc assumes surroundings lower than level – unusual !
20 dB(A) – a whisper – or very good voice studio,
25-28dB(A) – studio for radio, music, production, TV
30dB(A) – a quiet rural location or say a production studio not relying on accurate monitoring,
40dB(A) – a quiet office or living room
45dB(A) – A PC at 1m !!! - mine,
50DB(A) – Residential neighbourhood – general office,
60dB(A) – Conversation at 1 – 2m,
70dB(A) – Car at motorway speeds,
80dB(A) – Medium truck passing, petrol mower,
90dB(A) – Heavy truck passing or a typical nightclub!,
100dB(A) – Jackhammer,
110dB(A) – Rock band – too loud but the real world,
120dB(A) – Boeing 747 taking off – don’t build a studio on a runway
The (A) bit is a weighting factor that is used to mimic the way the human ear records sound.
You see the problem:
Depending on the monitoring or sound produced we really need to drop minimum circa 60dB(A) and if you are a rock band >80dB(A) i.e. equal to a nightclub alongside !!!
The truth is acoustic studios requires weight, significant sealing, acoustic doors and windows. Unless of course you are in the middle of a field and it is always dead quiet.