then yea, if your DAP doesnt have a built in eq youll have to get an amp that does... ZO2 as mentioned, several fiio amps, cmoy bbs, jds labs c5 and many many others come with this option.
the e11 you mentioned should be fine, it has a 3dB and 6dB booster. personally, i dont like its boost, as it boosts half the midrange together with the bass, and TO ME, its noticeable and changes the sound too much. thats why i prefer software equalizing. many users do use these hardware boosters and are very pleased.
the ZO2 boosts almost just the bass (i.e only slightly more frequencies than necessary, as opposed to most others). i have never used one myself, so i cant comment on it very much.
i think all the amps mentioned here have their own threads, check them out.