DiffusersWall · Ceiling

QRD Diffuser Panel Acoustic Properties \u2014 Absorption Coefficients (125Hz\u20134kHz)

Quadratic Residue Diffuser with mathematically-derived well depths that scatter incident sound evenly across a wide frequency range. Does not absorb sound — redistributes it. Used in recording studios, concert halls, and critical listening rooms to maintain liveliness while eliminating flutter echoes.

NRC
0.15
αw
0.10
Applications
Wall, Ceiling
NRC (Noise Reduction Coefficient)
NRC is the arithmetic average of sound absorption coefficients at 250, 500, 1000, and 2000 Hz, rounded to the nearest 0.05. QRD Diffuser Panel has an NRC of 0.15.
Reference: ASTM C423 / ISO 354:2003

Absorption Coefficients by Octave Band

Frequency (Hz)125250500100020004000
α (absorption)0.100.150.200.150.100.10
125 Hz
0.10
250 Hz
0.15
500 Hz
0.20
1000 Hz
0.15
2000 Hz
0.10
4000 Hz
0.10

RT60 Impact

Diffusers scatter sound rather than absorbing it. They do not significantly reduce RT60 but improve perceived clarity by redistributing reflections

Manufacturers & Brands

RPGVicousticGIK Acoustics

Frequently Asked Questions

What is the NRC of QRD Diffuser Panel?

QRD Diffuser Panel has an NRC (Noise Reduction Coefficient) of 0.15, calculated as the arithmetic mean of absorption coefficients at 250, 500, 1000, and 2000 Hz per ASTM C423.

Where is QRD Diffuser Panel typically used?

QRD Diffuser Panel is typically used as a wall and ceiling treatment. Quadratic Residue Diffuser with mathematically-derived well depths that scatter incident sound evenly across a wide frequency range.

How much does QRD Diffuser Panel reduce RT60?

Diffusers scatter sound rather than absorbing it. They do not significantly reduce RT60 but improve perceived clarity by redistributing reflections

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