"A recent study found that sound isolation earphones do a better job of reducing the outside noise signal than noise canceling earphones. A recent study compared the performance of Shure sound isolating earphones against three models of noise-canceling headphones and found that the sound isolating design was more effective at reducing the level of a broadband noise signal. The tests were conducted in accordance with recognized industry standards for measuring the noise attenuation capabilities of hearing protection devices and noise-canceling headphones."The study results revealed that the E3c with foam sleeves was the best performer as it reduced noise by 10 - 27 decibels more than even the best-performing noise-canceling model tested. Really interesting study. Read the article for additional benefits of sound isolating earphones.