POLY QRD 1D  set of 4 pcs. acoustic diffusers
POLY QRD 1D diffusers - an effective way of stopping FLUTTER ECHO direct sound reflections by dispersing sound energy in the room. The diffusers can be mounted on walls and ceilings and we recommend combining them with POLY50,  POLY50Q and POLY100 acoustic panels.
 
Technical specifications:
Central frequency: 1163Hz
Range: Scatter 581 Hz; Diffuse 1163 Hz; HF cut-off 6370 Hz 
Diffusion frequencies: 1163Hz; 2326Hz; 3489Hz; 4652Hz; 5815Hz 
Dimensions: 573mm x 573mm x 130mm (±2mm) 
Material: Polystyrene foam EPS-100 EN13163:2010+A1:2015 
Flammability class: E
Colour: white, black
Shipping package content: POLY QRD 1D diffusor (4psc.), special fasteners for mounting on POLY series panels.
Installation: In accordance with the manufacturer's recommendations. Can be mounted to POLY series panels with special fasteners or glued to surfaces with polystyrene adhesive.