G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
G10K11/08—Non-electric sound-amplifying devices, e.g. non-electric megaphones
Landscapes
Physics & Mathematics
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Engineering & Computer Science
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Acoustics & Sound
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Multimedia
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Circuit For Audible Band Transducer
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Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups
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