I recently spent £199 buying a pair of Bang and Olufsen H3 ANC earphones. These are supposed to provide Active Noise Cancellation that blocks out background noise. When you switch on the ANC feature, there is absolutely no discernable effect on the background noise that you hear. The quality of the earphones may be OK, but they do not provide ANC. If you want that, buy some Bose earphones, as I have now done and you will see what ANC can do.