This article is from the ZTerm FAQ, by Les Jones email@example.com with numerous contributions by others.
Absolutely. You can rename any sound to "Connect", "Filedone" or
"Termbell" and install the sound in the System file. Under System
7, quit all applications and desk accessories and drag the sounds
to the icon of the closed System Folder. When asked if you want the
sounds installed in the system file, click OK.
System 6 users can install sounds into the System file using the
Riccardo Ettore's shareware SoundMover (part of the SoundManager
Package) or Apple's ResEdit. You can also use a resource manager,
such as Fifth Generation System's SuitCase or Alsoft's
MasterJuggler, to open the sounds with ZTerm.