[TechnicallyDead]

So I'm in the market for a pair of "audiophile" headphones. To my understanding, there is more to getting the best sound than just an awesome pair of headphones.
 
I keep seeing DAC and amp popping up everywhere I look and regardless of my searches, I'm no closer to understanding which I need and why. I'm very confused. Is a DAC and an amp the same thing or are they two separate entitites? I got feedback from another forum that with lower impedance models (which i was told means how much power is needed to move the drivers in the headphones?) you don't need an amp. But then I keep seeing reviews for the 32 ohm models that they should be hooked up to an amp/DAC. 
 
Now I'm going to be plugging into my laptop and the sound quality from just the speakers is absolute **** so I figure it's a good investment to make in this amp. 
 
I'm not comfortable with buying headphones if I can't get clearly noticeable, good sound out of them. 
 
I've settled between Sennheiser HD558s or BRAINWAVZ HM5s. But I will make no move to buy them until I get this whole DAC thing cleared up.

 

[MrViolin]

A DAC is a digital to analog converter. Analog are the I's and O's. Analog is what we hear. In order to hear a file, a digital signal must be converted to analog. Mobos already have an onboard DAC, but how well it does varies. 
 
The amp's job is to amplify this signal. The amplification can be shown by gain (x5.0 for amplifying the signal x5). This strengthens the signal and thus gives more sound. 
 
They're 2 separate things. 
 
Ohms are rather secondary when it comes to how easy it is to drive a phone. The sensitivity/SPL (sound pressure level) is how much sound can be generated per mW (most of the time). The lower impedance means that it's easier for the phones to take in more voltage (or current). Thus why something like a hd800 will use less battery than something like an m-100. 
 
As for why they should be hooked up to an amp/dac, that could be possibly due to the 1/8 rule (with the phones have 8x the impedance value of whatever it is plugged in for minimal distortion). It also gives the phone to shine at its best depending on the amp and phone. 
 
Hope this helped in some way!

 

[bustersgotavmax]

It's all part of the chain starting with your music source, then DAC,amp  and then headphones. Improvements to any of these will give you improved sound quality. Good headphones will always sound better, but don't ignore the rest of the chain. My GRADOS for example benefit greatly from an external amp even though at 32 ohms it's stated they don't need one.
 
 If you look at home audio cd players past and present you'll find pricing from very cheap to a lot more expensive,this is due greatly to the quality of the DAC that's built into most  . It's the same for a headphone system. I have a mid to low range laptop with a onboard soundcard that sounds pretty good with my Grados,but my external DAC/AMP  blows it away,and it's not an expensive unit compared to what others have on this site either.