The Galaxy S4 has a very useful feature hidden in the settings. It’s called Adapt Sound and the difference in sound before and after is like night and day. I’m using the old ear phones that came with my Galaxy S2 and they’re fine for podcasts but after enabling this feature music is a lot clearer and richer. It’s quite amazing.
So, go into Settings, My device, Sound, Adapt Sound to run the sound test through your ear phones. Once that’s done and it only takes a minute or two and it will let you play a music clip with Adapt Sound on or off. The difference is quite startling.