Predefined RAVEL constants

tacet		    0 
ppp  		   10 
pp  		   24 
piano  		   34 
mp  		   44  
mezzo  	 	   54 
mf  		   64 
forte  		   80 
pf  		   94 
ff  		  110 
fff  		  127 
accent 	 	  127 
