Whir. A triangle wave at 440 Hz, originating from Subway Tunnel. Recorded in a container environment, era: 2010s. One of 5555 echoes — sounds no one thought to save.
Name
ECHO #1990 — Whir
ID#1990
Rarity
MID:31%
Frequency
440 Hz
X-HI:7%
Wave Type
Triangle
X-HI:8%
Resonance
Soft
X-HI:8%
Era
2010s
X-HI:7%
Origin
Subway Tunnel