Articles
Articles on sound isolation, treatment, RT60 and STI
Technical articles on hall acoustics: sound isolation, acoustic treatment, reverberation time RT60, the speech transmission index STI, acoustic ceilings and wall cladding.
Hall acoustics
Hall acousticsThe acoustics gate separates isolation from treatment, and reads RT60 with frequency, volume, and use instead of one number pasted on every hall.Sound isolationSound isolation stops transmission through the wall, the door, the duct, and the penetration. A laboratory Rw or STC is not a field result, and absorbent panels do not…Acoustic treatmentTreatment changes absorption and diffusion inside the room. A porous absorber is weak at low frequency if it is thin or hard against the wall. Coverage on a drawing is…Reverberation time RT60RT60 changes with frequency, volume, and use. One number for a hall type is a discussion target only. Sabine fails when absorption is high, and ISO 3382-1 is the…
Technical library
What is RT60?What RT60 is, why it changes with frequency, how ISO 3382 measures it, and when the Sabine formula misleads.What is STI?The speech transmission index from 0 to 1: reverberation, noise, how STI differs from RT60, and why “clear sound” is not a specification.Isolation versus treatmentIsolation stops sound moving between rooms. Treatment changes sound inside a room. Confusing them is the most common hall mistake.
Ceilings and walls
Acoustic ceilingsA cloud or a baffle adds absorption while the soffit stays open for services. A black ceiling over the stage is a visual decision and may still reflect. A mineral tile…Wall claddingWood and fabric reflect or absorb according to the cavity and the material behind them. Perforation without a cavity and an absorber is a texture. Fire and impact come…