Welcome to head-fi, sorry about your wallet. I think that's the greeting around here(i didn't grasp the ramifications at first, but now, woe is me, i do) In general, before posting a question, I would suggest doing a search, e.g for "portapro" and "review". Not to discourage questions, believe me, people here *love* to talk about headphones
But there may be times where you won't get a whole lot of responses because a topic has been done to death(like this one
Anways, a lot of people(including myself) like specific headphones in the lower end Koss line:
KSC-35 clips ons: $35ish
Sportapro: $30ish
Portapro: $50ish
In fact I almost never read about any of Koss' cans over 50 bucks.
If you can find the KSC-35 clip ons, the concensus seems to be they are the most balanced of the three. The Sportapros are a bit bass heavy which people like for running/exercising. They're fun but a little murky. I have the Sportapros and the KSC-35 clip ons and i find that at work, i listen to the KSC-35s more. They're nice and open sounding for jazz. But i can't use them for jogging because they slip off.
I'm not too familiar with the Portapros, but i think they all have a similar sound.. Any of them would be leagues better than the plasticrap that comes with a new portable music player.
Be careful though, once you go good can, you don't go back.
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Sony Earbuds: 19 dollars
Sportapros: 35 dollars
Grado's: 60 dollars
The look on your room mate's face when you tell him you can't pay rent as you tightly clutch your new Sony CD3000's : priceless