<p>Konzerthaus Ravensburg,
</p>
historischer Klangerzeuger: <a href="https://en.wikipedia.org/wiki/wind_machine" class="extiw" title="en:wind machine">Windmaschine</a>
Photo: Andreas Praefcke
CC BY 3.0
<span class="int-own-work">Self-photographed</span>