audio qualia 2

damping factors (from audio Qualia)

 

damping factor values  n [eta]

the damping factor values shown below have been determined by using a three axis accelerometer, Audacity software, and a bandwidth of 75Hz -1000Hz, 24dB/oct slopes, Q = 0.7071 . Samples were tested freely suspended in air.

 

 

material damping factor at frequency


Hz
wood
 
     
balsawood 0.013  
bamboo 0.200  
chipboard 0.101  
cork 0.050  
fibreboard (flooring) 0.257 113
hardboard 0.062 134
mahogany 0.032  
mdf 0.017  
oak 0.102 540
olive wood (oiled?) 0.273 264
panzerholz 0.387  
pine 0.064 226
Russian 7 ply 0.040  
torlyte (copy, ply+cork) 0.088  
walnut 0.044  
     
     
ceramics    
     
fired clay 0.012  
glass (strengthened) 0.033  
marble 0.009  
slate 0.017  
soapstone 0.027 1338
     
     
metals
 
     
aluminium 0.004  
brass 0.013  
copper 0.010 175
lead 0.032  
steel 0.008  
     
     
plastics
 
     
acetal (delrin) 0.013 121
carbon fibre/epoxy 0.022  
carbon /glass fibre 0.061 239
expanded polystyrene 0.055-0.168  
perspex (acrylic) 0.070  
polypropylene 0.052  
ptfe (teflon) 0.021  
vinyl foam board 0.046  
vinyl floor tile 0.145 272
     
     
viscoelastics and foams    
     
'blutack' 0.104  
closed pore foam 0.151  
expanded polyethylene 0.167  
foam for glass bricks 0.288  
foamboard (RPI Products) 0.030 94
polyurethane foam 0.054 120
polyurethane foam block 0.109 141
polyurethane foam reconstituted 0.149 82
plasticine' 0.301  
'Newplast' 0.398  
rho c (polyurethane) 0.287  
smart (silly) putty 0.134  
sorbothane 0.197  
tungsten loaded putty 0.318 102
Wickes' 'lead' flashing 0.161