U S I N G Y O U R Q E / Q V H E A D S E T
In the QE Headset, three noise cancelling modes operate together to provide 20 - 30 dB of noise reduction: First, the small size of the mic capsule and the short distance between front and rear ports reduces the sensitivity at 1 kHz to far field noise by 15 dB compared to the close talking response. Secondly, as shown in the frequency response graph below, noise at lower frequencies is
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| additionally attenuated. And, |
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| finally, the | ||
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dB (re 1 Volt/microbar) |
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| dB(re1Volt/Pascal) | pattern reduces signal coming |
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| CLOSE | TALKING |
| (1cm) |
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| from a 90° angle by 20 dB | |||||||
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| more (and random signal by 5 | ||||
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| dB more) compared to signal | ||||
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| originating from directly in front |
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| FAR FIELD (1m) |
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| of the mic capsule. | ||
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| 100 | Hz | 500 1000 2000 | 5000 10000 20000 |
| The frequency response of | ||||||||||||||
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QE Frequency Response
the QV Headset (which is virtu-
ally flat across the entire audible range) is shown in the illustration on the follow- ing page:
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