Total harmonic distortion: True, headphones with lower actual total harmonic distortion (THD) will sound better than those with higher THD. But the quoted THD numbers -- "less than 1 percent" -- aren't helpful in predicting sound quality. Listen to recordings of simply recorded acoustic guitar to assess the distortion of one set of headphones versus another. Some will sound appreciably cleaner than others.
Expensive: Audiophile-grade headphones can cost anywhere between $130 and $2,000. Headphones in this price bracket are no joke: they create impressive soundscapes, are robust enough for use in a recording studio, and they’re just plain beautiful. If you need a pair of headphones for critical listening, or you simply want the best headphones around, it’ll cost you.
Dale: The examples listed above are good general rules, but there also are so many exceptions and in-betweens that it also could be better to understand what is needed for your music, so you can narrow the search to the most appropriate headphones. For example, you may have heard that Classical music is a particular genre, but within that ‘genre’ are many very different types of music. Chamber music or pipe organ music may benefit from a headphone that’s highly detailed in the treble (a headphone that some users might say is bright), while harpsichord music and music that has a lot of strong trumpet sounds might be better served with a more rounded or softer treble.
Dale: There are so many types of amplifiers (and DAC’s with amplifiers) that there is no shortcut for studying all of the options, unless you settle for the most generic approach. Important things to consider are power – if you don’t have enough power for your headphone and the dynamics in the music, clipping will result. Sometimes the clipping is “soft” and not readily noticed, but eventually you would discover that much of the detail goes missing or gets veiled with limited dynamics. Another consideration is whether to use a DAC, which may be a separate DAC or built into the same enclosure as the amp. Most DACs will improve the sound over the DACs that are built into computers, but when a DAC is available to replace the DAC built into most cellphones and low to mid-priced music players, you can usually expect a much greater improvement.
An electret driver functions along the same electromechanical means as an electrostatic driver. However the electret driver has a permanent charge built into it, whereas electrostatics have the charge applied to the driver by an external generator. Electret and electrostatic headphones are relatively uncommon. Original electrets were also typically cheaper and lower in technical capability and fidelity than electrostatics. Patent applications from 2009-2013 have been approved that show by using different materials, i.e. a "Fluorinated cyclic olefin electret film", Frequency response chart readings can reach 50 kHz at 100db. When these new improved electrets are combined with a traditional dome headphone driver, headphones can be produced that are recognised by the Japan Audio Society as worthy of joining the Hi Res Audio program. US patents 8,559,660 B2. 7,732,547 B2.7,879,446 B2.7,498,699 B2.

Impedance: Generally speaking, the lower the headphones' electrical impedance (aka resistance), the easier it is to get higher volume. But here again, the low impedance is no guarantee of high volume capability; other factors can still limit loudness potential. Since many MP3 players have feeble power output -- the iPod is a notable exception -- smart shoppers should check the loudness before purchasing any pair of headphones. To be sure, listen with your player.
Their combination of dual balanced-armature drivers matched with a dynamic driver to pump up the lower end are kind of engineering normally found on products that cost more than double the price of the 1Mores. Even the smaller details are very well ironed out, such as Kevlar-wrapped cables that increase resistance to wear while simultaneously reducing tangles.
At the heart of the WH-1000xM3 is outstanding wireless sound. Sony’s LDAC technology delivers a wireless signal at what the company claims is three times the quality of standard Bluetooth streaming, and the headphones also support the latest aptX HD codec (with supported devices). The 1000xM3 even “upscale” wireless music from high-resolution audio devices using a special chip, helping to make music sound dynamic and beautiful, with authoritative bass and clear treble response held together by a well-rounded midrange.
If you have a bass problem you could find a filter of some kind that cuts the low bass. Some bass controls can do that. I haven’t found a music genre that totally lacks strong bass, although “acoustic” sometimes doesn’t have strong bass. Mainly, you should make sure your system is matched properly with amp and headphone, so the different frequencies are in balance. Then you will have better luck with different music.

I think it’s fair to compare the Grados and HD598, but the M50 is very different and seems not to fit in that comparison. The DT770 is a better comparison to the M50, although the 770 is a better more expensive item. A long time ago I had a Grado 325 and a Sennheiser HD565 – very similar, very enjoyable. Today for that type of sound I might choose the Soundmagic HP100.
What I’m saying here is that it’s better to own three $100 headphones than one $300 headphone. Or three $300 headphones than one $900 headphone. Why? Because most people don’t limit their playlist to strictly one genre. And following the logic from Rule #2, the right headphone-music pairing is going to be better than one expensive headphone paired to the wrong music.
I’ve had only a few minutes one day with a 598, so I can’t say exactly. But since the HP100 is closed and the 598 is open, I would get the 598, as long as open back is OK for you. I don’t think you can go wrong with the 598 in any case – it’s a very good headphone. Watch carefully for any cracks to develop though, since there were many reports of that.
Passive noise isolation is essentially using the body of the earphone, either over or in the ear, as a passive earplug that simply blocks out sound. The headphone types that provide most attenuation are in-ear canal headphones and closed-back headphones, both circumaural and supra aural. Open-back and earbud headphones provide some passive noise isolation, but much less than the others. Typical closed-back headphones block 8 to 12 dB, and in-ears anywhere from 10 to 15 dB. Some models have been specifically designed for drummers to facilitate the drummer monitoring the recorded sound while reducing sound directly from the drums as much as possible. Such headphones claim to reduce ambient noise by around 25 dB.
Communication headsets are used for two-way communication and typically consist of a headphone and attached microphone. Such headsets are used in a variety of professions as aviation, military, sports, music, and many service-oriented sectors. They come in all shapes and sizes, depending on use, required noise attenuation, and fidelity of communication needed.

Hi. I have more or less decided that the Philips Fidelio L1s are the ones for me. I plan to use them on my commute paired with an iPhone or the iPad as the source. I listen to a mix of pop, rock, blues and jazz so I’m not after boosting bass but I might want to fiddle with the dial on the treble and mids. Which brings me to my question. You state in your review that the L2s pair well with the Fiio e17 which lets you independently adjust treble and bass. Could the same effect be achieved lower down the $$ curve via a combination of say a Fiio E6 (for signal amplification) and a Dirac or Accudio app for equalisation?

The rule that I use is that the bigger the size of the headphone, the bigger the need for amplification. Of course factors like driver sensitivity and impedance will matter, but the general rule of thumb is, use a dedicated headphone amplifier for a full size headphone. Even a portable amplifier can be enough, depending on the type of the headphones.

These headphones rest on top of your outer ears and run the gamut from inexpensive portables to high-end home models. While on-ear headphones can have closed designs that cover the ears, some prefer fully sealed circumaural models (see below) for their increased sound isolation and the fact that they won't leak sound to neighbors. Still, the earpad headphone is preferred in places like office environments, where users still benefit from hearing the outside world.
Headphones are made in a range of different audio reproduction quality capabilities. Headsets designed for telephone use typically cannot reproduce sound with the high fidelity of expensive units designed for music listening by audiophiles. Headphones that use cables typically have either a 1/4 inch (6.35mm) or 1/8 inch (3.5mm) phone jack for plugging the headphones into the audio source. Some stereo earbuds are wireless, using Bluetooth connectivity to transmit the audio signal by radio waves from source devices like cellphones and digital players.[4] Due to the spread of wireless devices in recent years headphones are increasingly used by people in public places such as sidewalks, grocery stores, and public transit. Headphones are also used by people in various professional contexts, such as audio engineers mixing sound for live concerts or sound recordings and DJs, who use headphones to cue up the next song without the audience hearing, aircraft pilots and call center employees. The latter two types of employees use headphones with an integrated microphone.