Headphones are available with high or low impedance (typically measured at 1 kHz). Low-impedance headphones are in the range 16 to 32 ohms and high-impedance headphones are about 100-600 ohms. As the impedance of a pair of headphones increases, more voltage (at a given current) is required to drive it, and the loudness of the headphones for a given voltage decreases. In recent years, impedance of newer headphones has generally decreased to accommodate lower voltages available on battery powered CMOS-based portable electronics. This has resulted in headphones that can be more efficiently driven by battery-powered electronics. Consequently, newer amplifiers are based on designs with relatively low output impedance.
Music keeps me energized all day (and into the night) at work — 70% electronica/dance/DNB, 20% rock, 5% hip hip and 5% other/classical — but I’m tired of low-quality sound and I’m ready to put my money where my ears are.  I want to buy a USB DAC + Headphone amp, buy headphones (or, per your recommendation, to buy 2 pair) to complement the amp and my choice of music, and get great desktop sound for around $350.
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.
The problem is made even worse by the fact that Android phones can’t handle AAC in a method that approaches Apple’s performance with the codec. Consequently, we will no longer be recommending AAC-only headsets here at SoundGuys, as the experience is that broken from source to source. The results are crappier and noisier than the other codecs by a longshot.
Hey Mike, I’m a mixing Engineer looking to invest in a high end pair of headphones for when i’m forced to mix a song on the road. I already have the DT 770 pros and BEATS by dre headphones which i feel will be good enough for references. But I’m looking for a 3rd pair that really has a flat response and that is very detailed. I’m willing to spend $1,500 to $2,500. Are there any headphones you can recommend looking into. Thanks
Cable dressing and length: Most stereo headphones have just one cable, usually attached to the left earpiece (sometimes called single-sided cabling). Some models -- and all earbuds -- use a Y-cable that connects to both earpieces (double-sided). The actual cable plug, meanwhile, is usually one of two designs: a straight I-plug or an angled L-plug; the latter may be useful if your portable player has a side- or bottom-mounted headphone jack.
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.
Gaming headsets are headphones that have a microphone attached and allow users to speak to other people and hear them with the same device. In fact, gaming headsets have other practical applications as well. You can use them in business or personal situations when you want to speak to people on a computer using a video phone program or social media chat room. Although these work for music applications, they're more suited for conversational clarity.