Quanto vales em ópera?
Óperometro is an interactive installation that symbolically and playfully assesses participants’ “operatic capacity” and invites you to explore opera through vocal experimentation and knowledge. It is available at the entrance and exit of the “dentro de palco” shows.

Image: from the event entry at Agenda Porto.
Source: Agenda Porto (Câmara Municipal do Porto). Details can change; the original entry is the reference.