my first amp was the fiio e11. it was a high quality product but the bass effect wasn't enough for me. of course it was helping with the bass by reducing distortions on high volume levels but ap001 felt different to me. it's not a miracle device but you feel like you're getting all of the bass you can get from a little amplifier, undoubtfully (when used with a matching, easy to drive phones like koss kdx200).
i recently used fiio's e06, e11k & e12 but still couldn't able to get the same bass taste on the ap001. i don't know if my ears are fooled me but ap001's deep bass (30-60hz) was really felt a little fuller (especially when used with koss kdx200, the deep bass monster).
probably due to that dual output thing, it does not provides enough improvement to a single extremely power hungry devices like havi b3 pro I or brainwavz r3 or even devices like r1 (which has moderate needs). on the other hand, fiio e06 which is a similar small & cheap device, helps a lot to anything you throw on it. i tried to power both koss kdx200 and brainwavz s1 (this two are already very easy to drive earphones) with ap001 and that worked very well.
by the way, both e06 & ap001 produces a lot of signal noise when used while charging, but i think e06 is slightly worse because it ruined some songs i've tried. e11k is certainly better on this but pricier at the same time...
another concern of mine about the functionality of the device is, automatic on/off thing. it was opening itself when plugged into a powered sound source but not closing itself when there's was no song playing at all. for it to close itself, you need to shot down your sound source or unplug the cord. i was expecting something more complex. maybe i was expecting too much ?
here's the conclusion:
* it's not good for powering a single power hungry device, you should use e06 or something instead
* it's enough for powering 2 easy to drive devices simultaneously without showing any weakness
* it's deep bass boost is better than if not equal to what fiio offers
* i didn't felt any easy to notice difference in sound quality between ap001 & e06, e11, e11k and e12
note: this device carries a significant amount (~6 db) of ~125hz strong bass amplification by default (this has nothing to do with the 30-60hz deep bass feel i mentioned) i posted an explanation about this in the forum thread, here's the link: http://www.head-fi.org/t/735914/brainwavz-new-portable-headphone-amplifier-ap001/285#post_11088747
note 2: you do not need to worry and change your buying decision because of it's always on 125hz boost. if you do not want any bass boost, just use your equalizer setting and lower the frequency/frequencies near to ~125hz and you'll be fine.
note 3: i'm using old computer sound cards and especially audigy 2 zs when testing, which has a similar output power to the well known sansa clip series.
i recently used fiio's e06, e11k & e12 but still couldn't able to get the same bass taste on the ap001. i don't know if my ears are fooled me but ap001's deep bass (30-60hz) was really felt a little fuller (especially when used with koss kdx200, the deep bass monster).
probably due to that dual output thing, it does not provides enough improvement to a single extremely power hungry devices like havi b3 pro I or brainwavz r3 or even devices like r1 (which has moderate needs). on the other hand, fiio e06 which is a similar small & cheap device, helps a lot to anything you throw on it. i tried to power both koss kdx200 and brainwavz s1 (this two are already very easy to drive earphones) with ap001 and that worked very well.
by the way, both e06 & ap001 produces a lot of signal noise when used while charging, but i think e06 is slightly worse because it ruined some songs i've tried. e11k is certainly better on this but pricier at the same time...
another concern of mine about the functionality of the device is, automatic on/off thing. it was opening itself when plugged into a powered sound source but not closing itself when there's was no song playing at all. for it to close itself, you need to shot down your sound source or unplug the cord. i was expecting something more complex. maybe i was expecting too much ?
here's the conclusion:
* it's not good for powering a single power hungry device, you should use e06 or something instead
* it's enough for powering 2 easy to drive devices simultaneously without showing any weakness
* it's deep bass boost is better than if not equal to what fiio offers
* i didn't felt any easy to notice difference in sound quality between ap001 & e06, e11, e11k and e12
note: this device carries a significant amount (~6 db) of ~125hz strong bass amplification by default (this has nothing to do with the 30-60hz deep bass feel i mentioned) i posted an explanation about this in the forum thread, here's the link: http://www.head-fi.org/t/735914/brainwavz-new-portable-headphone-amplifier-ap001/285#post_11088747
note 2: you do not need to worry and change your buying decision because of it's always on 125hz boost. if you do not want any bass boost, just use your equalizer setting and lower the frequency/frequencies near to ~125hz and you'll be fine.
note 3: i'm using old computer sound cards and especially audigy 2 zs when testing, which has a similar output power to the well known sansa clip series.