First 2 samples defective in Passive mode, so rating is for Active mode only (both samples identical in Active noise cancel mode). Overall sound very bassy, but responds very well to i-device bass reduction, resulting in excellent high fidelity sound with strong (but not excessive) treble and very strong bass (after reduction!). Batteries seem to last a very long time in Active mode. Can be worn around neck all day when not in use. The sound quality is remarkably good and very smooth - the best I've heard for $200. If Passive mode should prove good and reliable on future samples, that merely increases what is already a very good value.