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Hey ppl just looking for some advice, i found this site about 2 weeks or so ago when trying to find some decent headphones i could afford, i ended up getting a  Audio Technica ATH-A900x, i've only have it for about 2 days now, but wasn't sure how to get the best quality out of them.
 
I own an iphone 4, ipad 1st generation, and my desktop pc has a creative fatal1ty titanium sound card. I was wondering what type of audio quality i should be looking for, like 128k or 192k?  also a friend told me instead of mp3 i should check out audio format called flac. I'm pretty new to this whole high end audio scene, so what should quality and format should i be find, to get the most out of the headphones and which device that i own should i use, or must i upgrade and get a better sound card?
 
Edit:
 
If someone can post a link to another forum post with this information i'd appreciate it

 

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There are many opinions on which compressed audio type sounds the best.  There no doubt that any compression is a bad thing.  That means going from a CD to an mp3 will cause some sort of loss via compression.  Many of us have done direct A/B comparisons using a CD as a reference and 192kbps or better compressed mp3 files and can hardly if at at hear the difference.  Some loss can definitely be heard going from CD to say 160kbps compression.
 
Some things to listen for are cymbal crashes, chimes, or any other high frequency treble.  Compression typically occurs by limiting the number of data points or terms used to represent the original signal.  This turns into removing higher order and thus higher frequency data from the original waveform.  When listening for differences between compressed and uncompressed audio pay particular attention to the treble.  This includes the treble and the amount of it itself as well as location cues.  A more compressed file will have less treble and fewer location cues so the audio may sound 2-D rather than 3-D.  Echo and acoustic ringing may also be limited.
 
In the end you really do not have to worry about it especially if you cannot hear the difference with your current gear, but as a rule of thumb I rip my music to mp3 at or above 192kbps.
 
You can check for yourself at these sits and see if you can hear the difference:
 
320kbps v 128kbps
http://mp3ornot.com/
 
General mp3 or not tests:
http://www.pcworld.com/article/195957/music_compression_test_how_good_are_your_ears.html

 

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Thanks for that break down of the compression and what to listen for, i will use your rule of thumb as a base mark and re-rip my CD's at 192kbps, will also do some digging to find out what my music that i own on itunes was compressed at. I'm pretty sure that should be easy to find in google.