Groan 83. A sine wave at 888 Hz, originating from Subway Tunnel. Recorded in a open air environment, era: 1990s. One of 5555 echoes — sounds no one thought to save.
Name
ECHO #2755 — Groan 83
ID#2755
Rarity
LO:52%
Frequency
888 Hz
EX:3%
Wave Type
Sine
X-HI:13%
Resonance
Soft
X-HI:8%
Era
1990s
X-HI:9%
Origin
Subway Tunnel