[Sonic Atrocity]

Okay, so I have pretty much decided that I am going to purchase the DT 48 E. As far as I know my options are limited to the 25 and 200 ohm DT 48's. My understanding of impendence is quite lacking and I don't understand why there isn't just one impendence. I am looking to achieve a flat frequency response in my setup and understand that in order to drive my headphones properly and achieve my goal then I will need an amp. I will be commuting a lot so I am thinking of a portable amp. I currently have two concerns. First concern being that I have heard portable amps are not worth it. But, I am willing to spend money in order to achieve maximum quality.  Secondly, I made another thread in regards to acquiring a DAP that would make a flat frequency response possible. I learned that it doesn't matter what DAP I use as long as I am using an amp that can run my setup. Thus, I would be able to achieve my flat frequency response. Is my understanding correct? 
 
In fact, I have yet another concern. Do I need a DAC? Any advice in regards to all my questions and concerns would be very helpful! Thanks for taking the time to read my post.
 
Edit: Perhaps this is obvious but I plan on using my DAP at home instead of the computer.

 

[tvrboy]

I have a DT-48e and it's just fine from any portable device. Of course an external amplifier will improve sound quality a little bit, but it's so sensitive you don't need one. A portable amp in my opinion isn't even worth it, it's bulky, expensive, and you don't need it with the 48e. An external DAC will really improve sound quality, but maybe you should just buy the headphone first. Listen to the headphone for a while before you buy any other equipment. I dunno about the difference between the 25 ohm and 200 ohm, Kool Bubba Ice will probably come here any minute and tell you that...

 

[Sonic Atrocity]

Hmm, I have learned though that an external amplifier will aid me in achieving a flat frequency response. I was told that the DAP I have won't affect frequency response as long as I have an external amp. Hence, I would get something like the ipod touch (it can carry 64GBs and is compatible with apple lossless which my files are in). 

 

[Sonic Atrocity]

Ahh, I need more responses! *bump*

 

[kool bubba ice]

Using a GOOD portable is give you good sound, but they really benefit from upstream components, more so then some 250-300 ohm headphoneds, which defies logics, but it's what I hear... More then other sensitive & low ohm headphones I owned like the AD700.. I'd get a used PICO with the DAC option.. Stellar reviews.. Also check my team xbox blog. I list 28 portable amp/DAC combo's ranging from 50.00-1,600..
Quote:

Hmm, I have learned though that an external amplifier will aid me in achieving a flat frequency response. I was told that the DAP I have won't affect frequency response as long as I have an external amp. Hence, I would get something like the ipod touch (it can carry 64GBs and is compatible with apple lossless which my files are in). 

I just gave you some..
Quote:

Ahh, I need more responses! *bump*

From what I hear the 200 ohm are more upfront & slightly less detailed with less speed.. This is based on a owner who has two newer DT48 models.. He drives both with a SP amp & has no problems.. My 200 ohm version is vintage & really different then any DT48 I have heard so I won't include it..
Quote:

I have a DT-48e and it's just fine from any portable device. Of course an external amplifier will improve sound quality a little bit, but it's so sensitive you don't need one. A portable amp in my opinion isn't even worth it, it's bulky, expensive, and you don't need it with the 48e. An external DAC will really improve sound quality, but maybe you should just buy the headphone first. Listen to the headphone for a while before you buy any other equipment. I dunno about the difference between the 25 ohm and 200 ohm, Kool Bubba Ice will probably come here any minute and tell you that...