Noise cancelling is most effective for repetitive low level frequencies (like engine noise) but will not block higher level frequencies (like people talking) as much as these frequencies are needed to allow sound to work in the headphones.
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For Sennheiser PXC 550 Ear Pads Headphone Earpads For Sennheiser PXC550 Ear Pads Headphone Earpads Cushion Earmuff Cover
Aliexpress UK
Highly portable travel headphones - such are the PXC 250 mini headphones with NoiseGard™ active noise cancellation technology. New pads fitted. Closed design ensure excellent passive attenuation of ambient noise, allowing you to enjoy your music without distractions.
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OKCSC Headphone Adater Dual 3.5mm Female to SENNHEISER HD650 Male Connecter for SENNHEISER HD580/HD600/HD650/HD25/HD660S/HD565
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New pads fitted.
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OKCSC EAR Female to SENNHEISER IE300 Connecter Earphone Adater for SENNHEISER IE300/IE600/IE900/AKG N5005 N30 N40/MMCX S535
Aliexpress UK
Highly portable travel headphones - such are the PXC 250 II headphones with NoiseGard™ active noise cancellation technology. Closed design ensure excellent passive attenuation of ambient noise, allowing you to enjoy your music without distractions.
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New Sponge Replacement Ear Pads for Sennheiser PC5 Chat PC 5 Headset Parts Foam Cover Earbud Tip Cushion Earmuff Pillow
Aliexpress UK
Sennheiser PXC 550 Wireless BT NoiseGard Adaptive Noise Cancelling Headphones Product Code 506514. Noise cancelling is most effective for repetitive low level frequencies (like engine noise) but will not block higher level frequencies (like people talking) as much as these frequencies are needed to allow sound to work in the headphones.
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Earpads for Sennheiser HD4.50BTNC 4.40 4.30 HD350 400S 458BT Headphones Ear Pads Cover Cushions Earphone Replacement Earpad
Aliexpress UK
Highly portable travel headphones - such are the PXC 250 mini headphones with NoiseGard™ active noise cancellation technology. The switch is in the On position on the Noisegard unit, headphones work as they should but to turn them Off, the batteries need removed.
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Upgraded Perforated Sheepskin Replacement Headband Cushion Compatible with Sennheiser HD800 HD800S HD820 Drop HD8XX Headphones
Aliexpress UK
Highly portable travel headphones - such are the PXC 250 mini headphones with NoiseGard™ active noise cancellation technology. New pads fitted, a spare set included. Closed design ensure excellent passive attenuation of ambient noise, allowing you to enjoy your music without distractions.
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Replacement Ear Pads For Sennheiser HD 560S 558 559 555 518 515 HD400 Pro Headphone Accessories Ear Cushion Memory Foam Cover
Aliexpress UK
Highly portable travel headphones - such are the PXC 250 II headphones with NoiseGard™ active noise cancellation technology. Closed design ensure excellent passive attenuation of ambient noise, allowing you to enjoy your music without distractions.
eBay
Velour Earpads For Sennheiser HD25 HD25-II Headpohone Replacement Headset Ear Pad
Aliexpress UK