Pop 57. A square wave at 220 Hz, originating from Subway Tunnel. Recorded in a open air environment, era: 1920s. One of 5555 echoes — sounds no one thought to save.
Name
ECHO #1541 — Pop 57
ID#1541
Rarity
LO:68%
Frequency
220 Hz
X-HI:8%
Wave Type
Square
X-HI:10%
Resonance
Soft
X-HI:8%
Era
1920s
EX:4%
Origin
Subway Tunnel