This will end up being a very short and sweet knowledge base article here, and I thank you for making the effort to look at our FAQ section in order to look for help. I hear time and time again from our customers that their new Momentum in-ear earbuds sound tinny or that their new HD598se from Amazon is "lacking a full sound and there is no bass". If you have sound issues like this it's because your cell phone or .MP3 player has a weak audio power output and our headphone is being underpowered, hence it sounds hollow and is lacking punch, power, and bass response. You MUST buy an amplifier for your new headphone if you are having this tinny sound issue, because if your headphones already sound great to you then it means your laptop or audio source actually already has a decently powerful audio card/output in it. Here is an example for where to start when getting into the vast world of headphone amplifiers. I always suggest starting with a rechargeable/portable headphone amp made by a company that we here in Technical support have come to love called Fiio out of China. Fiio makes some of the worlds best small portable headphone amps, and I own the A3 model (love it) while one of my coworkers just bought the A5 (love it too). Here are some links below for both models.