The bandwidth requirements of the bluetooth speaker are very strict, especially the low-frequency part of the small-diameter full-frequency speaker. It can be said that the low-frequency sound quality of the bluetooth speaker determines the sound quality of the bluetooth speaker .The main factors that determine the low frequency of a bluetooth speaker are: magnetism, voice coil, cone and design. In terms of magnetism: the magnet of a small-caliber full-frequency bluetooth speaker generally uses rare earth high-strength magnets that are magnetically strong and do not demagnetize. We are speaker supplier, welcome to contact us.