Headphone Audio On A Budget

While much is said about headphones, for people just getting into things, I believe it's important to keep things as simple as possible, and the spending list as trimmed down as can be. Hence, here is a list of headphones that need no amplifier to work well:

==========within 100 USD==========

Sennheiser HD 201

It's cheap, it works, and it sounds alright.
It also has what is called the "Sennheiser Veil", which is typical of most of Sennheiser's headphones up until around the 5XX line. Simply put, it sounds "dark", as if the treble has been toned down.
Nothing more to be said, asides perhaps its long cable and not-so-good earpads.

Koss PortaPro
Grado SR-60i

These two headphones get quite a lot of buzz about them, especially because of their ridiculously good value for money - not to mention the PortaPros with their lifetime warranty. A lifetime warranty for a fifty Dollar product! Really!
The PortaPro, as its name suggests, is quite portable. Very small, light, and folds. However, the Grado is very much not so, due to its 3 foot long, super-thick cable. In any case, both do not fare well in the outdoors, where their open-backed cups leak sound inwards and out (mostly the former), ruining the sound, your hearing, and relationships with whoever's beside you. I won't bother to comment much on these since I'm pretty sure you're looking for a close pair of headphones (do let me know if you're interested though).

Denon D1000 and D1001 (NOT the D1100) / Creative Aurvana Live!

A slightly less common suggestion within the 100 Dollar range are these headphones which, despite the different branding, are essentially the same headphone drivers in different housings. They have a "fun" sound, which is sort of like a V-curve (some emphasis on bass and high frequencies), and are close-backed. They aren't too large that they feel like a burden either, and they have decent pleather (fake leather) earpads. Decent on anything, really.
If you're heading the Denon route, make sure you get the D1000 or D1001, and NOT the D1100; the former two were made by Fostex, also a Japanese company that does great headphones, while the D1100 is some monstrosity that was issued after Fostex decided to split off from Denon. They are completely and utterly different.

AKG K518 LE

Another less common headphone. While AKG's most well-known can is definitely the K701, no small thanks to K-ON!, the K518 is a completely different piece of work. Small, portable, with a really short cable (like maybe 1 foot, tops). It rests directly on your ears and clamps harder like a, well, you know. The isolation is amazing, the bass is really strong and punchy, and it generally works quite well with less subtle music - electronica, pop, and such. Doesn't match well with classical, jazz, or things that need subtlety.

==========within 200 USD==========

Audio Technica ATH-M50

The most recommended headphone in the history of ever. For good reason of course, it's comfy and around-the-ear, it's close-backed and isolates decently, has a very full, rich sound because of a slightly enhanced mid-bass, works with generally anything, and isn't picky about where you stick it in. Overall, it's a very safe headphone because there's a pretty good chance you'll like how it sounds.
My main issue with it is that it is huge - truly a "full-size" headphone. It's not heavy, but certainly something that could feel like a burden when resting around your neck, and the cord is pretty long too. Unless of course you get the M50 with a coiled cable, which feels like you've got a phone cord attached. Note that it folds for portability.

Sony MDR-V6 / MDR-7506
/g/'s new headphone-that-everyone's-supposed-to-have, and again, for good reason. It's much thinner and lighter than the M50, with a slightly smaller earcup (still a full-size headphone though). If the M50 was rich and full, the MDR-V6s are neutral and clinical. Chances are, you've seen these in any professional audio studio, because they are THE industry standard headphones for monitoring stuff. Cheap (enough), robust and sturdy, and the sound is always reliable. It may feel a little bass-light for untz-untz however, and the cord is a problem as well. Don't be put off though, as this headphone sounds amazing for its price - it's been in production for nearly 30 years now and it's not hard to see why. This also folds like the M50s. The MDR-7506 is exactly the same, but is the "professional" version, with better warranty, but also slightly more expensive.

V-Moda Crossfade M80

One headphone that gets overlooked a lot is the Crossfade M80. It's a much less-known brand, but the sound is a great match with anyone who likes deep-reaching bass. They are also very portable and they look really cool. On-ear however. I can't really give much more detail as I haven't had much time with them.

Beyerdynamic DT 770

The DT770 is another pretty common headphone, but - and that is a very important but - you will need an amplifier to get the best out of these. Not like the piddly FiiO E3/5/6, but something like the E9/11 or so. The sound is somewhat similar to the Denons, with better bass, but harsher highs.

Sennheiser HD 25 (and variants)

Essentially the AKG K518, but better in every single way.
Note that the HD 25 SP is somewhat different-sounding, with a different kind and level of build quality. However, it does have more value for money.

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Do I need an amp for my PC/mobile audio?

Short answer:
For the above headphones (asides the DT 770), no you do not.
These all have been picked specifically because they are not picky on amplication, and work well with anything.

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Do I need a DAC?

Remember:
DACs alone are not going to work, as they only output a line level signal. You need an amplifier to go with the DAC, to amplify that signal to listenable levels. Just that most products like phones and PCs already have both.

>On a desktop
Most onboard sound is workable - better if you have a proper, separate soundcard. Volume control can be a pain however.
>On a laptop
Depends. If your laptop is a cheap Acer or something, you probably do. However, most laptops' onboard sound is acceptable enough, and most headphones within the 100~200 USD price range aren't too picky about bad audio sources.
>On a mobile device
Most mobile devices will have a decent enough DAC, unless you're using some cheap Chinese knockoff. iPods, phones, and pads, as well as any decent smartphone or digital analog player (Sansas, Cowons, Walkmans), have a good enough DAC for entry-level audio. Usually DACs are primarily for computers.

How can I tell if I need a DAC for my computer?
Easiest test is to get a decent headphone, listen to something on your phone/portable audio player. Plug it into your computer, fix the volume, and listen again. If it sounds like crap, you should probably get one.

If you do want a DAC, I suggest:
The FiiO E10. It's a USB-powered combination DAC and amplifier the size of an Altoids tin. You can use it for your laptop and desktop, and it's plug-and-play. It has a decent attenuator (volume control) and can power most headphones within 200 USD. Has a line-level out if you want to use it only as a DAC. Also has a coaxial out in case you want to output your PC audio to a receiver and speakers. Best part: 75 bucks on Amazon.

But if you have the scratch:
Get the Schiit Magni and Modi. One's a DAC, one's an amp. 100 Dollars each, but they will last you a long, long time, through a great number of headphones.

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Hope that all helps.