So sánh phương pháp

	Ống trở kháng	Chỉ số cách âm
Lĩnh vực	Âm học	Âm học
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1866	1961
Người khởi xướng	August Kundt	ASTM International
Loại	Acoustic absorption measurement	Building partition acoustic rating
Công trình gốc	ASTM E1050-19 (2019). Standard Test Method for Impedance and Absorption of Acoustical Materials Using a Tube, Two Microphone and a Digital Frequency Analysis System. American Society for Testing and Materials.	ASTM E413-16 (2016). Classification for Rating Sound Insulation. American Society for Testing and Materials.
Tên gọi khác	kundt tube, resonance tube, acoustic absorption, sound absorption coefficient	STC, sound transmission loss, acoustic isolation
Liên quan	5	5
Tóm tắt	An impedance tube (or Kundt tube) is a laboratory apparatus for measuring the acoustic absorption coefficient and surface impedance of materials. Originally developed by August Kundt in 1866, the technique has been standardized by ASTM and ISO for characterizing noise-control and acoustic-treatment materials. The impedance tube method is simple, portable, and cost-effective, making it the industry standard for pre-design acoustic material selection and quality control.	Sound Transmission Class (STC) is a single-number rating used to describe how well building elements (walls, doors, windows) reduce sound transmission between adjacent spaces. Standardized by ASTM International and ISO, STC is calculated from sound transmission loss (STL) measurements across the speech frequency range (125 Hz–4 kHz). It is the primary metric used in building codes, product specifications, and acoustic design to ensure privacy, noise control, and occupant comfort.