[bassballboy]

[size=medium]I want to preface this with the fact that I have NO knowledge about headphone amps/sound cards. [/size] [size=medium]I'm looking for something to use with my Sony XB500's to enhance their low end (playing with them on super bass tracks shows me that they have the ability to put out much, much more bass than I'm currently hearing).  Will getting an amp solve this or are there some better eq's or soundcards out there that will accomplish this?  [/size]

 

[NA Blur]

The first thing you will want to do in order to get even more bass is to make sure you are listening to bass heavy music.  Trying to squeeze bass from tracks that have no low extension is not going to yield more bass.  It will however introduce distortion and other terrible artifacts that will not be very pleasant.
 
That said there are often two ways to improve bass extension.  The first is improving the DAC section of the audio chain.  This can improve bass by giving further accurate low frequency generation when the bass signal is present.  If the DAC is rounding off the low end then the bass is being limited.  I would expect most low cost soundcards and certainly many on-board soundcards to not have much bass at all.
 
The second method is by introducing an amp that has good control of the low end by having a deep mastery of frequencies lower than 100Hz.  Not all amps do well with low frequencies.  Having an amp with a low output impedance can help control low end distortion because of damping.  See the speaker damping wiki for more details.  Basically your headphone impedance divided by the output impedance of an amp needs to be over 10 if possible.  For example if I use a pair of Denon AH-D2000 headphones that have an impedance of 25 Ohms then in order to meet the rule of 10 the output impedance of my amp should be 2.5 Ohms or less.
 
Damping Math:
Headphone Impedance / Output impedance of amp must be 10 or greater
Example:
25 Ohms / 2.5 Ohms = 10
 
This shows how well the amp can control the drivers especially at the fundamental frequency which is almost always somewhere toward the bass frequencies.
 
I am guessing you are not currently using a nice soundcard?  If not I suggest something like the Total Bithead from Headphone.com.  The Bithead is built really well, time tested, works both on batteries and via USB power, serves as both a USB DAC and headphone amp.  It should give your headphones and entire audio chain a nice kick.

 

[RPGWiZaRD]

I suggest Digizoid ZO2, 32-lvl bass boost adjustment. I think XB500 + ZO2 will leave your face shocked at how strong bass output a pair of headphone can do, when I had this combo lvl 2-3 was usually right, anything more was too bassy even as a basshead.
 
And if that's not enough a good quality EQ will also work, such as is bundled with Creative X-Fi cards.

 

[PurpleAngel]

Quote:

[size=medium]I want to preface this with the fact that I have NO knowledge about headphone amps/sound cards. [/size] [size=medium]I'm looking for something to use with my Sony XB500's to enhance their low end (playing with them on super bass tracks shows me that they have the ability to put out much, much more bass than I'm currently hearing).  Will getting an amp solve this or are there some better eq's or soundcards out there that will accomplish this?  [/size]

Your Sony XB500 are 40-Ohms and add-on sound cards will come with an impedance of 10-Ohm or higher.
So any sound card will automatically increase the bass on your XB500, just may not make a very good sounding bass.
Portable headphone amplifiers seem to come with a much lower impedance then sound cards or motherboards.
Something like the Fiio E10 USB-DAC-Headphone amplifier will enhance the over all sound quality, over whatever motherboard your plugging your XB500 directly into.

 

[bassballboy]

thanks all!  Are there any good, inexpensive EQ's for headphones?  I might pick up that Fiio E10 sometime, though it costs as much as the headphones .  And that Z02 sounds exactly like what I want, but at $100 it's a it pricey..

 

[PurpleAngel]

Quote:

thanks all!  Are there any good, inexpensive EQ's for headphones?  I might pick up that Fiio E10 sometime, though it costs as much as the headphones .  And that Z02 sounds exactly like what I want, but at $100 it's a it pricey..

Maybe get the Fiio E6 or a low cost cmoy headphone amplifier.