
ertönen
to sound / ring out
The sudden or clear becoming audible of a noise, melody, or signal.
Als der Vorhang aufging, ertönte lauter Applaus im Theatersaal.
When the curtain went up, loud applause rang out in the theater hall.
to sound / ring out
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to sound / ring out
The sudden or clear becoming audible of a noise, melody, or signal.
Als der Vorhang aufging, ertönte lauter Applaus im Theatersaal.
When the curtain went up, loud applause rang out in the theater hall.
'Ertönen' (to sound/ring out) is an inseparable verb. The prefix 'er-' always remains attached to the stem 'tönen' (to sound). Here it signals the beginning or sudden occurrence of a sound.
Plötzlich ertönte ein lauter Knall.
Suddenly, a loud bang rang out.
The perfect tense of 'ertönen' (to sound/ring out) is always formed with the auxiliary verb 'sein' (to be). The reason is that the verb describes a change of state—from silence to sound.
Pünktlich um zwölf Uhr ist die Sirene ertönt.
Right at twelve o'clock, the siren sounded.
The subject of the verb 'ertönen' (to sound/ring out) is always the sound itself or the source of the sound. People or animals cannot 'ertönen'.
Aus der Ferne ertönte leise Musik.
Soft music sounded from the distance.
Common subjects for this verb are signals and sounds. Typical examples are: a signal, a melody, a call, applause, a bell, or a siren.
Als der Sieger ins Ziel kam, ertönte die Nationalhymne.
When the winner reached the finish line, the national anthem rang out.
to sound
Klingen usually describes an audible sound or the way it is perceived. Ertönen, by contrast, emphasizes that a noise, melody, or signal suddenly or clearly becomes audible. Use klingen for the nature of the sound and ertönen for the moment it begins.

Plötzlich ertönt der Alarm im Gebäude.
Suddenly, the alarm sounds throughout the building.
Der Alarm klingt schrill und laut.
The alarm sounds shrill and loud.