[ f o r   D O S B o x - x ] 
 
 
 
 T y p e   o f   G r a v i s   U l t r a s o u n d   t o   e m u l a t e . 
 
 
 
 c l a s s i c   :   O r i g i n a l   G r a v i s   U l t r a s o u n d   c h i p s e t 
 
 c l a s s i c 3 7   :   O r i g i n a l   G r a v i s   U l t r a s o u n d   w i t h 
 
                                   I C S   M i x e r   ( r e v   3 . 7 ) 
 
 m a x   :   G r a v i s   U l t r a s o u n d   M A X   e m u l a t i o n 
 
                     ( w i t h   C S 4 2 3 1   c o d e c ) 
 
 i n t e r w a v e   :   G r a v i s   U l t r a s o u n d   P l u g   &   P l a y 
 
                                   ( i n t e r w a v e ) 
 
 
 
 P o s s i b l e   v a l u e s :   c l a s s i c ,   c l a s s i c 3 7 ,   m a x ,   i n t e r w a v e . 
 
 