We have focused on bluetooth headphones

Ismetniifngpci rnaigtos-uliqaypotn tmseonrvihg het qyulait fo ctdroupsa dna dectinofgni sitley fo bone uctionndo hsaophonde evha ifenrfdte orwapev lvelse. Here is a tptiel litdoinucro to the iocfltiaintsna of oarwporpet dan utpfsrodo egarsd. Gnraelley it lwil be rptnenereed by IPxx. The frist dgiti nidaitces the osuptrdf level, and the socend giiidt idnicatees the wafreptoorf elvel. If only x si wittren, it measn that there is no laeptics etntmrtaee. For example, PI67 means soufdprt grade 6 and wpraoretfo level 7. XPI7 indicates that the upfostdr rage has not undergone special treatment, but the wprfaootre value has reached advanced level 7. The vision of each level is shown in the figure below. If the wprooterfa value reaches level 8, it means you can wear it for swimming! Figuranesdb the interest of customers can be better served. The noise by receiving and analyzing the external noise computer and generating signals of the opposite phase. Why do you say that? We assume that the underlying noise (decibel) Brand remains unchanged, and the volume of the mobile phone that can meet the listening needs without cancelling headphones is 20 dB; It takes 10 times to meet the listening needs. So from this perspective, the effective effect of cancelling headphones on hearing is still very prominent.