Buying headphones can be a confusing decision with so many kinds to choose from, let alone understand. If you've ever wondered at some of the terms used or what the advantages of each type are, read on.
We'll get into discussion of major headphone designs and even cord information below, but first there are two items that bear mentioning to better understand what follows. First, since air pressure plays a big role in how we hear, a headphone's seal is important in the way they will sound. Second, headphones at the most fundamental level come in two designs: open and closed. What this means essentially is that a headphone is either sealed off from the outside or vented to allow air (and sound) to pass freely.
Open vs. Closed Design
Generally open headphone designs are described as being more "natural" sounding, but this can come with drawbacks. Everything going on in the room around you will intrude on your music. This can occasionally be useful, but is often a hindrance that requires turning the volume up higher. Also, your music leaks out just as easily, which can bother others nearby if the area is otherwise quiet.
Closed headphones on the other hand offer a much more intimate listening experience and are nearly silent to those around you. The one disadvantage compared to open designs is that the bass can be muddier or certain other sound characteristics overly pronounced.
MAJOR TYPES OF HEADPHONES
These are among the most common headphones in the mass market, largely due to their portability. They are light, easy to shove in a pocket, and fit right in your ear. Earbuds are inexpensive and easy to find in any store that sells electronics.
Being this small can come with a cost. The downside of earbuds is that they lack the driver size and the isolation to produce a high-quality listening experience. Models have varied slightly in size and shape attempting to improve upon this dilemma, but ultimately it is what it is. A common price ranges for this type is $10-50.
Earcup designs are the other most common type of headphone. Many of the behind-the-head style headphones you see are great examples. These are larger than earbuds, and work by sitting on the ear rather than in it. This larger design allows for a fuller range of sound and better power handling, but still lacks much of a seal between the ear and headphone. The result is the loss of detail and bass compared to other types. Still, this design is also inexpensive and easy to find, and still pretty portable. Typical price range for this type: $15-50.
Supra aural headphones are larger still from the earcup design. They work again by sitting on the ear, but cover the entire ear and create a better seal by contact pressure (produced by the headband). This pressure can sometimes be uncomfortable for long listening sessions.
Overall range and detail are improved in this design from earcups, but at the cost of portability. These tend to be bulkier and heavier, but lighter than the circum aural designs we'll discuss in a minute. Essentially, this type of headphone tries to play the middle ground between earcups and full-size headphones. Even in a closed design, however, supra aural headphones will leak sound. These tend to range from $15-100.
These are full-size headphones and are as un-portable as they come. They are usually the heaviest and bulkiest type of headphone, but offer several advantages.
Because the pads go around the ear, they are typically more comfortable. This method also creates the best seal you'll get other than canalphones, resulting in the ideal dynamic range. Headphones of this size often have large drivers, making them efficient and able to handle more power without distortion. The size, too, affects range in a positive way.
Open designs will still leak music or let ambience in, but the area between driver and ear still benefits from the seal. Closed circum aural headphones are ideal in this sense, being nearly silent to anyone nearby and blocking out a great deal of outside noise. Because those that purchase this style of headphone are often audio enthusiasts, build quality and price reflect this niche market. Prices tend to vary from $25-500, though it's not unheard of to see circum aural headphones at $1000 or more.
Canalphones or In-Ear-Monitors (IEMs)
These are the newest style of headphone, aiming to bridge the gap between portability and sound quality. They are as small as earbuds and also go in the ear, but unlike earbuds they go into the ear canal like earplugs. This takes some getting used to for some users.
The major advantage of being inserted into the ear canal is isolation. Canalphones offer all the audible advantages circum aural designs have due to their seal, and can often block out even more outside noise. Because of both the seal and the proximity to the inner ear, dynamic range is dramatically improved compared to earbuds. The user will not have to turn the volume up as high and will also appreciate a much greater level of detail in listening as a result.
Though a bit more expensive, canalphones will outperform earbuds sonically in every way, and can prove to be just as portable. Cheaper models are in the same general price range as earbuds and earcup headphones. The higher end canalphones, though, can be just as costly as full-size headphones.
There are different cord designs employed with headphones as well. The simplest distinction to make is the general shape the cord makes-in most cases a "Y" or "J". "Y" cords resemble the letter, wherein a single strand comes from the plug end and splits off to connect to each earcup. The "J" design, as it applies to earbuds and canalphones, starts with a singular strand and splits off. The difference from the "Y" cord is in that one side is longer than the other, meant to be wrapped around the back of the head and then go to the ear. This relieves some cord tension and makes it harder for the earphone on that side to be pulled out, however it can also be cumbersome. The third major configuration in cords is a straight cord, meaning it comes from the plug all the way up to what is usually the left earphone. It connects there, and the wire for the right side feeds internally through the headband. This is nice in that externally there is only one wire to deal with.
Many high-end headphones will use the "Y" cord rather than the straight design so that each side is exactly equal length. At this level, there is a degree of pickiness that insists each side is sonically matched as closely as possible.
Balanced and Unbalanced Cord Setups
You may also hear certain headphones being referred to as "balanced". On a regular cord, the positive line is carried up each side, but one way or another the ground wire becomes shared. Even on a "Y" design where each side has its own wire, the grounds join at the end where the wire terminates into the plug. A balanced design essentially means that each side is completely separate, having its own positive and negative wire that never touch the other side. Doing this requires each side have its own plug at the end, which of course means you'd need a special output device to connect the headphones. Most devices use a stereo plug, whether 1/4" or 1/8".
Why, you ask, would someone want a completely separate connection? No matter how clean the connection is and how high quality the wire transmitting the signal, two ground signals crossing can always create interference or noise. This can be difficult to hear, which is why usually only extremely high-end headphones appear in a balanced design. Again, at that level the sensitivity of the headphones themselves and the ears of the audiophile may benefit from a design that minimizes any sort of audible noise whatsoever.
Does using a balanced cord design make a big enough difference to bother? This is a topic of debate among audiophiles. Most would agree the difference is small, but it remains a matter of opinion on how important that small difference is.
OFC and 7N Cables
OFC stands for oxygen-free copper. Cheaper copper wires are more prone to interactivity that can cause noise in the signal. A hiss or small levels of distortion are sometimes observed when using such cables. Higher end cables minimize this interference for the cleanest signal transmission.
Some of the highest end cables are called "seven 9's", or 7N cables. This refers to the number of decimal places in the oxygen-free rating. This appears as 99.9999999% oxygen-free. No cable can claim to be 100% free of anything that would cause interference, but these cables as you'd guess are as close as audibly possible.
On some higher end headphone models users claim that replacing the stock cables with expensive aftermarket ones improves sound quality notably. This, too, is a topic of heavy debate in the audiophile community. Many users insist that silver lined cords have a very different sound, for example, than copper or gold-tipped wires. Others maintain that's all in people's heads. What everyone does agree on is the importance of oxygen-free copper.
Gold-Tipped Plugs - What's That About?
Gold itself is less conducive than copper, which is one of the reasons (the other being price) that the wires themselves are not gold. So then why all the fuss about gold-tipped plugs and adapters? Gold does not tarnish or corrode like copper does, so a partially gold connector or adapter is another way to ensure the cleanest signal transmission over time.
Since the plug of a wire is the only part that contacts air and therefore is susceptible to corrosion, it's the only part that benefits from a gold mixture. Stay away from any expensive cables that claim the whole wire is gold or partially so-you're just throwing your money away for a gimmick.
So that's about it. Hopefully with all this in mind the questions in headphone buying will be a bit easier to understand. There are of course still other factors in any audio equipment to consider. This should get you started at least and on your way to making an informed decision when mulling over which pair of headphones are right for you.