I personally use these headphones to go running with a source shuffle Apple. I am satisfied, they hold firmly in place and do not isolate too from outside. The sound is very clear, especially for middle and treble very "detailed". I expected a little more bass deep, but it is quite acceptable. These headphones are well worth the more expensive headphones and often less comfortable to wear. I also appreciate the angled jack connector which limits the length of the source, when connected. In the end, good buy.