Janos Gereben wrote about Grand Macabre:

>Boder, who will conduct the Oct. 29 premiere, spoke about the "complicated
>score...  sounds you never heard in an opera house before...  a large
>percussion group, with car horns, paper bags"

Actually Havergal Brian's opera The Tigers calls for a motor horn though
the opera has never been staged.  Some circuses used to have an act with
a sea lion playing tunes on motor horns.  I wonder Ligeti ever considered
doing this, the lights dim enter sea lion stage left to honk the beginning
of the opera.  Perhaps Ligeti was unsure whether a sea lion with sufficient
competence could be found.  Would one advertise for a grade one in motor
horn?

Tim Horwood