Assertion: noise cancelling earphone | /r/HasProperty | closed-earsystems
Facets:
value: in practice
type: TEMPORAL
Source sentences:
text: But in practice, the noise-cancelling earphones I've seen are "closed-ear" systems that attempt to also use passive means to keep as much outside noise "out" as possible, and in so doing, they tend to also keep the counter-noise "in".