harpin14789Based on the pad type you might see a difference in the bass quality since you are affecting the seal you get around your ears. Leather pads will give a better seal, which produces a bassier sound. Whereas velour pads provide better comfort, but the seal around your ears isn't as great. Ultimately, velour pads will produce a cleaner bass, but the bass will not be as prominent as it is with the original pads. Also, you might experience some sound leakage with the velour pads, which means people might be able to hear your music and you might external sounds. Note that most of the changes you'll experience are really minimal, and most people won't really notice. Regardless, there will be some slight change to the headphone's sound signature.