Talking Audio When it comes to both describing and understanding how a headphone sounds a headphone related vocabulary might come in handy. Unlike processor, RAM and other PC components headphone performance is largely unquantifiable. Now some will argue that it is possible via frequency response-charts, distortion measurements and so on, however, through my experience those are completely inadequate when it comes to the general performance of a headphone. The most useful measurable performance aspect in my opinion is square wave performance. This is the aspect which to my ears best correlates real world performance with measurable performance the best. Even though it is the best it is still only describes a very small part of a headphone’s performance. You cannot describe all aspects of a headphones sound in a review, or with words. The amount information is simply too great, you would need to hear them to understand every aspect of their sound. However a few words about a set of headphones can describe its general trends. Vocabulary Air - A airy presentation is associated with good sound stage reproduction that lets you "hear" the space between instruments. Analytical - Term often used with headphones that are good at portraying minute details. Balanced - A headphone which has an adequate amount of bass, midrange, and treble. Bloated - A headphone with too much, bass and or mid bass. Blurred - Opposite of fast. Ill transient response causes the headphones to sound dull to listen too. Transients get smeared and loss of detail is massive. Bass - Usually tones produce with a frequency ranging from 16 Hz (lower boundary of human hearing) to 200 Hz Cold - The opposite of warm. The lack of coloration gives a more sterile type of sound. Where the term warm is attributed to a musical sound, cold is used for headphones with a more analytical nature. Crunchy - Odd upper midrange and treble response emphasis undesired details in the music- Extension - Extension refers to how high or how low a frequency can be reproduced audibly. Highs - See treble. Linearity - How flat the frequency response is. A headphone with a totally flat frequency response is analytical and has a linear frequency response. A headphone with limited linearity can be favourable because it allows for ie. accentuated bass, mids or highs. A good example is the JHAUDIO JH|16Pros their bass is linear but raised a few dB over the rest of the spectrum. The Etymotic ER4-series earphones are linear across the entire frequency range. Muddy - Bad transient response performance, lack of PRaT. Mid bass - A fuzzy area between 150 - 250 Hz, share similar characteristics with bass rather the midrange. In extreme cases can cause the sound to appear like coming from a tube. Midrange - 200 Hz to 2000 Hz, normal range of a voice. Some would argue the most important frequency area due to the fact that it has the most information. Neutral - Not adding or subtracting anything to the original mix, truest to recorded sound Natural - Highly subjective term used with headphones that are not analytical sounding per say but still produce a very credible midrange (predominantly) PRaT - Pace Rythm and Timing, associated with audio equipment that exhibits good transient response. Lack of PRaT generally gives a dull/bland sound. Sound stage - Big sound stage means that the perceived listening environment is large. The space between instruments and how precisely you can locate them plays a big part in the sound stage reproduction. Sibilance - An issue with some headphone and speaker designs, where a rapid elevation in frequency response around 3000 Hz causes S's to sound way to dominant. A sibilant headphone often causes rapid listening fatigue and makes female vocals sound harsh and sharp. Synergy - Can be said when two or more components complement one another nicely and boost the experience Treble - Above 2000 Hz, an area dominated by strings, flutes, high-hats, and falsetto voice. Warm - A term used to describe whether or not the headphone has a slightly elevated mid-bass that adds presence to low frequency vocals thereby exaggerating a woody quality in the tone. Think metal box vs. wooden room. Note: Subject to change without notice, I will be updating it regularly. Last update: 09-05-2011 Where are we? - Frequency response and characterization of their sound From Headphone.com. Above you can see a frequency response comparison of the following headphones: beyerdynamic DT770 (80 Ohm version), Head-Direct HiFiMAN HE-5LE, Ultrasone PRO900, Monster Dr.Dre Beats. As you might have noticed the Monster Beats are incredibly bass heavy. The bass bleeds into the midrange to an extent where details in this range are severely compromised, the Monster Beats are to these ears a perfect example of a bloated sounding headphone. Treble response (above 2000 Hz) is far from ideal. Due to the bump around 2000 Hz these headphones sound very sibilant. The Ultrasone PRO900s exhibit the same behaviour but not as extreme. Detail preservation wise the PRO900s comparatively maintain way more throughout the frequency range and generally sound more balanced, even though their frequency response graph is close in some areas to that of the Monster Beats. The HE-5LEs have a slightly forward midrange representation which is depicted in this graph. The rolled off treble is also audible. The peak around 10 kHz actually brings them close to the ideal frequency response (ideal means completely flat from the users perception, due to the ears less sensitivity and dampening in some areas the measured frequency response needs to have a bump around 5000 Hz see image below). From Etymotic.com. As you can see the difference between the user perceived response and actual measurable frequency response is quite big, almost 10 dB at 10 kHz (for every 3 dB the energy doubles). Programs and good links Frequency Generator, learn what a frequency sounds like you might get surprised Home of the best analytical tests of headphones. They use a top of the line test rig.