(I'd go right out and say go ahead and buy them if your budget were to be in that range if it weren't for the fact that different people need different styles of headphones. Quality in audio is often (to a degree) subjective in nature.)
Hopefully an improvement over what I had in the OP previously, the new OP is effectively just a copy-paste of information from Head-fi.org, easily the most knowledgeable community for headphones on the internet. Any high-level questions should betaken there if possible, as should all questions involving headphones above the $500-mark. Ebay is an acceptable option that's often cheaper, give using it some thought. (It carries risks as always though.)
Things I've seen in the thread frequently that need to be addressed:
1. Don't buy a 'head-set', don't even consider it. Buy a desktop microphone for around $20, separately from your headphones.
2. If someone hasn't answered your question within a few days, send me a PM and I'll do my best to help you.
3. Use Foobar2000 for playing your music, see the additional resources at the bottom of the OP for more information.
4. See how to post below.
How to make a post: (i.e. Use this convenient pre-made form)
Before buying headphones
1. Think about the whole system and budget for that. I can’t stress this enough. There are really good sounding headphones to suit almost any budget and any system requirements, but you really need to know what you’re getting into. Don't just think about the headphone. If you’re looking to buy a headphone, you also need to know what else you need (or don't need) to make it sound good. If you’re buying a reference quality headphone, they most often (not always) require dedicated home components to bring out the qualities that people talk about. That’s just the way it is. They require a well-matched amp that can drive them well. Many will be revealing of poor quality recordings and low bit rate downloads if you’re using your computer. If, for example, you're interested in the HD650 because you’ve read it’s good, just know that you might be disappointed if you don’t amp it properly, and if you amp it properly, you might be disappointed in the sound you’re getting if your source and/or recordings don’t cut it. On the other side of things, there are really good headphones that sound just fine without an amp and straight out of an ipod or computer soundcard if that’s what you want. You can get good sound in a lot of different ways at almost any price point, but research what you’re looking for, and put what you need in your budget before you decide on anything. It will actually save you money in the long run.
2. Portable amps aren’t the answer. Okay, sometimes they’re the answer, but mostly when portable headphones are involved. I know I’m going to get grief for this one, but so be it. I like portable amps, have owned some really nice ones, and have listened to a lot more. They are great for portable headphones, and do okay with some headphones designed for home use, but they do not take the place of a decent dedicated home amp when using headphones that were created for audiophile listening at home. Sure, they’ll make your headphones louder, but loudness does not equal sound quality, which is the real purpose of amplification. A properly driven headphone sounds amazing at very low volumes. If your lifestyle dictates that you need portability, then I suggest researching the many excellent choices in headphones that are not demanding when it comes to amplification. Don’t rush out and get a K702 because you heard it’s great with classical and expect to hear anything close to how it can sound with a portable amp. If you’re choosing a headphone that needs a amp, a portable amp may be a good stepping stone if you’re slowly building a system like I and many others did, but again, be aware of the compromise you’re making, and be happy with whatever you choose. Just think: if portable headphones were the best option for all headphones, no one would be making home amps, and that’s just not happening.
3. Source matters. Yes, it does. High quality headphones reveal your source. That’s their job. Garbage in, garbage out. I love my ipod, but when I’m using it, I choose headphones that sound good, but are more forgiving of my source’s flaws when listening. If I were to use one of my more revealing headphones, I wouldn’t be enjoying the music nearly as much. Whether you consider getting a good dac, a dedicated cdp, or lod for an ipod, there are a lot of different ways to go. For portable, I like choosing forgiving headphones and not worrying about amp or source; for home, I prefer the best cdp I can afford, and one day, I'd like a good turntable. Others may choose differently, but if you’re looking at getting high quality headphones, know that they’re only as good as what you’re feeding them.
0 - amp useless, or worse
1 - amp unnecessary
2 - amp recommended
3 - amp needed
4 - amp included
!!! - specific version(s) have problems
DC - discontinued
XE - fakes are common
CO - must be Custom Ordered from manufacturer
DJ - good for DJ work: Good seal, rotating cups, stands up to abuse
Format: PREFIX - AMP # - Full Name (version) [price range in USD]: notes
1, 2 Kanen KM-92 Wooden IEM [$5-$12]. Very low price point and good SQ for the price. Bass is fairly prominent, and the fact the headphones are made out of wood are nice perks as well
1 - Koss KSC75 (rightangle plug) [$13-$15]: Best bang for buck phones anywhere. Very good for modding.
$20 - $70
1, 2 - Soundmagic PL-50 [$52]: Phenomenal sound at a bargain price. Somewhat analytical sounding with great detail for the price-point. Not biased toward any genre of music. A great deal especially considering these are balanced armature IEMs.
2, 3 - Brainwavz M1 [$39.50] More balanced Dynamic driver IEM. Less bass than it's more expensive relative, the Brainwavz M2. Less definition in the trebles as well. Really requires an amplifier more than any other IEM in this price range, but sounds more laid-back.
1, 2 - Brainwavz M2/ViSang R03 [$59.50] Another great sounding headphone at a fairly good price. Not as analytical as the SoundMagic PL-50's, M2 has warmer and smoother, and there is more bass. These are not balanced armatures, however, if that makes any difference.
1 - Koss PortaPro [$35]: Grado-like sound at a cheap price. Takes mods very well, such as Kramer's mod. KSC75 clips improve sound and portability. In recent years the cable has become super thin and useless, recabling would be ideal.
1- Sennheiser PX100 [$35]: Amazing bang for buck.
Open On Ear
Grado - i80 - Not a large sound stage, sounds better with an amp, but not needed for a good all around flat sound. ($100 USD)
Grado - M1 - Similar to the i80, but pushes more on the low end. ($100 USD)
DJ, 1 - Shure SRH-440 [$65-$125]: Compare to Sony MDR-V6, possibly overthrowing it. Flatter response. Very good seal; Bulky but comfortable. Can upgrade to SRH840 memory foam pads for more comfort. Detachable Cable, Collapsable design good for transport.
DJ, 1 - Sony MDR-V6 [$65]: King of the price range and category since the 80's. Dependable buy with great bass response and nicely detailed highs. Very comfortable and makes a good seal. Can Upgrade to Beyerdynamic DT250 velour earpads very easily for only $20. Single entry, Coiled Cable, nickel plated connector. Can be found refurb'ed occassionally for $35, which is a must buy.
1 - JVC HA-RX700 [$35]: An inexpensive version of the A900. A fairly balanced signature for its price range, albeit a little laid back. Large, not great at isolating, a slight recessed midrange and possibly boomy bass, but for the price, the detail and overall sound balance is absolutely great.
1 - Grado SR60i [$69]: Great mids. Amazing with rock and guitar. Highs can be harsh and lacks bass. Supra-aural. Great value and entry into the Grado house sound.
$70 - $150
XE, 1,2 - Monster Turbine [$109]: Great bang for buck. Small soundstage but gets better after a good break in.
1,2- RE0 [$79]: Amazing bang for buck, great mids and all around very solid performer with no major flaw, male vocals sound slightly sucked out or recessed, decent isolation.
1,2 - RE-ZERO [$99] Much like the RE0, this 'updated' version features better bass, and less agressive highs. Worth considering if too much treble bothers you.
0,1 - Ultimate Ears Super.fi 3 [$60-$100] Good trebles, very solid build construction, and low impedence. Comparable to PL-50. Detachable Cables are a nice touch.
1,2 - Realvoice[$89], beautiful and silky mids and deep and controlled bass, crispy high, great for vocals, instrument, decent isolation
XE, 1 - Audio Technica ATH-ES7 [$100]: Closed. Poor isolation. Fun sound, very stylish but easily scratched. Folds flat and comes with velour bag.
Audio Technica M50 [$100-$120] needs an amp, preferably a warmer one (at least an E5) to offset its recession in the midrange.: Great bang for buck, good isolation, fun sounding but not overly colored, folds up for easy transport. VERY good bass response/impact which adapts well to the music.
2 - AKG K271 [$150]: Great mids. Comfy and decent isolation. Too bass light for some, blu-tack mod recommended for those who think bass is not enough.
2 - Ultrasone HFI-580 [$150] Initially clamps hard. Great highs. V-shaped EQ means fun sound but recessed mids. Epic bass. BeatsbyDre-killing bass. Tight bass but capable of deep rumble. Not as transportable as M50 but does fold up. If purchased, do listen to the Ultrasone sample CD: S-Logic Plus adds interesting twist to sound. Good isolation. Doesn't need amp but benefits greatly from one.
1 - Audio Technica ATH-AD700 [$85]: Good for Gaming, Movies (very open soundstage). Good bass response but not bass presence (not thumpy). Comfortable and very very very large.
CO, 1 - Alessandro MS-1 [$100-$110]: Comparable to Grado SR225, based off SR80, not super comfortable. Very Aggressive, forward sound. Great Value.
2 - AKG K242HD [$100]: Very comfortable semi-open design. Lush midrange with good bass, but treble is slightly rolled off.
DC, 3 - Sennheiser HD580 [~$150]: Very similar to the HD600, especially if you change the grills. Somewhat laid back sound with very good mids, slightly rolled off highs and solid bass. Comfort can be lacking for some due to clamping, but this can be fixed.
$150 - $250
2,3- Etymotic ER4P/S [$175]: analytical, high detail, great isolation.
2- Audio Technica CK10 [$230]: Clean, full sounding.
2- Ultimate Ears TripleFi 10 [$230]: Cold and analytical sound signature may not be for everyone. These have some sibilance with some songs.
2- Sennheiser HD25-1 II [$175]:
2- Fisher Audio FA-003 [$170-240]: Neutral sound signature with lots of detail and great soundstaging. Sound is very fast and fun. Versatile and works well with many genres. Also available as FA-002w if you want wooden cups.
2- Denon AH-D2000 [$200-230]: Great bass and decent soundstage with a laid back sound. Doesn't isolate well. Top notch comfort. Great with trance and bass heavy music but a good all around can.
1- Ultrasone HFI-780 [$180-230]: Tight, punchy bass, crisp highs with an aggressive, upfront sound. Lots of bass. Good isolation. Great with trance and bass heavy music.
2- Beyerdynamic DT770 Pro (80 ohm) [$150]: BASS!!! Great soundstage for a closed can. Very good movie and gaming can.
1,2 - Shure SRH840 [$150-$200]: closed, circumaural. Built like a tank, so great for traveling. Relatively neutral overall, with ample bass.
1- Grado SR225i [$200]: Treble heavy Gradoish sound that is brilliant for rock music although some may find it too bright.
$250 - $500
1,2 - Monster Turbine Pro Copper [$279]: Great dynamic range, sound stage, presence with incredible bass presentation. Mid foward. Very cool looking.
DC, 1 - Audio Technica ESW10 [~$500]: Warmish natural sound. Great looks and good comfort. Only little isolation, good in the city but not for subway use. Considered one of the best portable headphones around but is overpriced when you consider the fact that the M50s provide similar sound for around 120 dollars.
1,2 - Audio Technica ATH-ES10 [$400]: Strong visceral bass, neutral mids, smooth and sparkly highs (though not grado-ish). So-so isolation, comfy (not so much as denon d1001), big soundstage, simple but elegant design. Good build quality. One of the best portables present to date (2010)
1,2 - Bose QC15 [$299]: The best active noise canceling headphone by far. Good sound stage and presence. Light on the bass. The noise cancellation might distort the music though.
3 - Denon D5000 [$420]: Warm, bassy sound.
2 - Ultrasone Pro 750 [$300]: Good bass not overbearing but with plenty of slam (an all around more refined version of the HFI-780). Good comfort. Great with trance and bass heavy music.
3- AKG K701 or 702 [$250]: Extremely detailed with a large soundstage. Some feel anemic bass dependent on amping.
3- Beyerdynamic DT880 (600 ohm) [$290]: Very flat, neutral sound. Excellent and accurate soundstage. Very good for gaming.
2- Audio Technica AD2000 [$500]: Open, airy soundstage with very lush forward midrange and great speed. One of the best for female vocals.
3- Beyerdynamic DT990 (250ohm) [~$250]: Semi-Open, great soundstage, natural sound especially when paired with tube amp, present but controlled bass.
3- Sennheiser HD600 [$300]:
3- Sennheiser HD650 (300ohm) [$350-$400]: Circumaural, open. Upgraded version of the HD600 with better soundstage/
2- Westone ES3X [$850]: Warm, lush sounding custom IEM. Forward sound signature places you on the stage together with the instruments.
3- Denon AHD7000 [$670]:
DC, 3 - Stax SR-404LE [$700]: Electrostatic headphone. Limited edition of the Lambda design, with real leather and new cable. Good natural sound, slightly warm, detailed. Very comfortable.
CO, 2 - JH13 Pro [$1,099]: Incredibly detailed reference sounding custom IEM's. Natural and open sound.
CO, 2 - JH16 Pro [$1,149]: Stupendous bass presentation while retaining all of the positives from the JH13 Pro's.
3- Audez'e LCD-2 [$945]: Planar Magnetic Headphones. Neutral, fast, tonally rich, deep bass, seductive mids.
3- Beyerdynamic Tesla T1 [$960]:
3- Sennheiser HD800 [$1400]:
DC, 4(2) - Sennheiser HE60 [~$1800]: Electrostatic headphone. Nice natural sound, very detailed, slightly bass light. Normally comes with HEV70 amp but using another amp is recommended. Very comfortable.
3- Stax SR-007 "Omega II" [~$2150]: Open-Back Electrostatic Earspeaker.
3- Stax SR-009 [~$5250 USD]: Top-of-the-line electrostatic earspeaker. Latest production model.
3 - Stax 4070 [$2000]: Electrostatic headphone. Designed for monitoring, very detailed and unforgiving. A bit heavy but good comfort.
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