A Glicol file with no out: line produces silence with no error message

In Glicol, only a chain named exactly out: reaches the speakers. Bus chains (prefixed ~) are signal wires, not audio outputs. If the out: line is renamed, deleted, or accidentally omitted, the result is complete silence with no parse error or warning. This is one of Glicol’s two main silent-failure modes (alongside undefined bus references). Every valid Glicol file must have exactly one out: chain.

Examples

~main: sin 110 >> mul 0.2 — silent, no error (it’s a bus, not out:). Fix: out: sin 110 >> mul 0.2.

Assessment

Explain why a Glicol file that defines only ~ buses produces silence, and name the one chain name that makes audio audible.