bass is very difficult for headphones to get right, on one hand there are people that see bass as something that thumps and makes things move, on the other hand you have those that see it as a sound that is part of the music. i myself love bass it is the foundation of music in which the rest is built on.
now in regards to headphones/IEM's , bass varies wildly from thumping vibration to smooth deep sound. below 20hz the human ear will not hear the bass however it will feel the bass, ''pro'' grade headphones or those classed as high end will generally do whatever it takes to reduce the vibration as this resonance is not a natural part of the sound, or in other words it shouldnt be there and is only there because of the materials used and how they respond to the frequency. this is why alot of people hear high grade stuff and simply dont understand where the bass is because there cheapo stuff booms and vibrates hard.
this is the decision you need to make, i have the IE8 also and it does pretty well at hammering out the bass with fairly controlled chamber resonance however it can start getting out of control with massive volume and the bass turned up. you should take into consideration that although the vibration can make you think wow its hittin hard, at the same time it can become uncomfortable, the earphones will start to tickle and you will be pulling them out to jab a finger or two in its place, very nice.
in the ideal world the bass would kick your head in yet the earphones will cope admirably, hence more luxurious materials and experimental designs being used to battle the problem.
what im saying is if you want thumping hard bass dont head straight for the high end stuff because most people have to gradually make progress to appreciate...the progress. jumping straight in the deep end more often than not will leave you wondering what the fuss was about. ever wondered why you see so many complaints about messy bloated bass with cheaper earphones well my explanation is partly why.
