I'm looking for an MP3 Player around $300 or less (willing to go up if it's something really good). I want something with at least 64gb, good/great audio quality, great battery life (30+ hours), and bluetooth would be a plus but not necessary. I'm kind of new to Hi-Fi. Recently purchased Sennheiser HD 598 Cs and Audio-Technica ATH-S700BT. Would like to have a great value MP3 Player for long flights and long weeks in the field (Army). Thanks in advance!!!

ok, heres the problem.
 
higher end mp3 players are usualy crippled battery life wise by their amps, offers from A&K, FIIO and other high end DAP´s will only run for around 8-12 hours due to a mixture of the high cpu load decoding higher end sound files (DSD, 24Bit flac and such) and the high power amplification from the headphone out.
 
on the other hand decent players with good quality but that might not have the power to push such headphones will run for 30--40 hours without issue, but the low output power will surly leave you with either very low volume or a flat lifeless sound signature.
 
so...
 
The only player that ticks all your boxes that i know of is the sony A35, it costs around 250 bucks but you have to import it from asia from a seller like accesoryjack, it has a 35mW HP out, unless you´re playing DSD with noise canceling it will easly cross the 30h mark and costs around 250 bucks.

When I search for the Sony A35 all that comes up is a camera. Did you mistype the name or am I being slow? 

tdaniels903 said:

  When I search for the Sony A35 all that comes up is a camera. Did you mistype the name or am I being slow? 

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You should search for 'Sony 'NW-A35', there is also an existing thread for this
http://www.head-fi.org/t/815843/new-sony-nw-a30-series
 
Also, you may want to look at the 'Cowon Plenue D', it has playback of up to 100hrs and costs $250-300
http://www.head-fi.org/t/789488/cowon-plenue-d

wskl said:

   
You should search for 'Sony 'NW-A35', there is also an existing thread for this
http://www.head-fi.org/t/815843/new-sony-nw-a30-series
 
Also, you may want to look at the 'Cowon Plenue D', it has playback of up to 100hrs and costs $250-300
http://www.head-fi.org/t/789488/cowon-plenue-d

Click to expand...

What's the difference in audio quality between the two?

tdaniels903 said:

  What's the difference in audio quality between the two?

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Sorry I do not own either device, you would have to ask in those 2 threads.