Pirunkirkko (“Devil’s Church”) is one of the famous caves in Finland. Tradition says that this Crevice Cave leading inside the Koli mountain was a meeting place for sages, who typically used sound to contact the spirit world. Today, the place is visited by practitioners of shamanism, who organise drumming sessions at the back of the cave. This paper examines Pirunkirkko and the related traditions from the perspective of acoustics, hypothesising that the acoustic characteristics of the narrow crevice might have played a role in the ritualization of the place and the power of its sonic rituals. Methods employed include impulse response recording, spectrum analysis, archival research, and an interview of a shamanic practitioner analysed with discursive psychology. The results indicate that the corridor-like back of the cave houses a distinct resonance phenomenon. A standing wave between the smooth parallel walls generates a ringing tone at 230 Hz that stays audible after sharp impulses or tones vocalised at the same frequency. Surprisingly, the local folklore or the interviewed practitioner do not mention this ringing tone at all. Instead, they speak about the “spirit of the cave,” “special energy,” or “new horizons” opened up by drumming. This leads to reflection on cultural frameworks of thought that guide sensory perceptions leading to differing experiences and interpretations.