Locks.
Small isolation booths, often used to isolate guitar amps!
Where are they?
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Specs
- 16 m2 / 170 sqft
- Height: 4 – 4,5 meters (13 – 15 feet)
- Length: 7 meters (23 feet)
- Width: 2 – 2,5 meters (6,5 – 8 feet)
- No parallels between walls, or ceiling and floor, to avoid standing waves
- Inaudible air-conditioning, due to large conducts, result: NR5
- Natural daylight
- Ideal for vocals, acoustic guitars, amps etc.