CONTENTS

 

 1     Scope 
 2     References 
 3     Abbreviations and acronyms        
 4     Loudness rating parameters for telephone sets      
 5     General algorithm for loudness rating calculations  
 6     Calculation of SLR and RLR        
 7     Calculation of STMR       
 8     Calculation of LSTR        
Annex A – Fundamental principles of loudness rating calculations     
        A.1     Introduction          
        A.2     Definitions and symbols concerning sound pressures, sensitivities and transmission losses     
        A.3     Structure of the theoretical model  
        A.4     Values of the parameters   
        A.5     Calculation of loudness ratings       
Annex B – Fundamental principles of calculation of sidetone masking     
        B.1     Calculation from first principles      
        B.2     Calculation of STMR using W weights       
        B.3     Comments on sealed versus unsealed conditions for the calculation of STMR         
        B.4     Calculation of LSTR using W weights         
Annex C – An alternative form of the loudness rating algorithm     
Annex D – Weighting coefficients for the band 100-8000 Hz     
Annex E – Calculation of the listener's sidetone factor D     
        E.1     General  
        E.2     Non-linear microphones and/or circuitry     
        E.3     Linear microphones and circuitry    
Annex F – Computation of the sidetone sensitivity SmeST     
Annex G – Wideband loudness rating algorithm