The Truth About Headphones

What even is quality audio?

How do you describe it is what I mean. We all know if something sounds good or bad (from our own perspective at least), but describe to me what some properties of good audio quality are without naming a brand of audio products.

Audio quality is in the ear of the beholder. Give the same set of headphones to 5 different people and they will all have something different to say about them. We are forced to make these purchases without hearing what they sound like first though, it’s a little unfair, but there are ways to overcome the ignorance of the average consumer and the marketing of the audio companies. Beats and Bose have us all fooled that headphones of good quality cost over $200, when often the components within $50 headphones are almost identical, with only the speaker driver itself being the difference.

Time for some audio mumbo-jumbo, bear with me.

Let’s look at how headphones work.

http://img.ehowcdn.com/article-new-thumbnail/ehow/images/a04/ld/8p/headphones-work-800×800.jpg

This is the most simple headphone design. The electrons are arranged by the processor of the source device (iPod, mp3 player, etc.) which travel through the copper speaker cable to an electro-magnet. The electrons react with the magnet, which then vibrates the speaker coil at the correct frequencies, which is turned into sound that is amplifier by the diaphragm.

 

http://upload.wikimedia.org/wikipedia/commons/8/85/Es_spk.gif

This is a picture of how an electronic signal is converted into air pressure fluctuations (sound).

 

There are other features that modern headphones include, and the manufacturers would like you to believe that their technology is brand new and revolutionary.

Noise cancelling was discovered in the 80’s and Bose started selling noise-cancelling headphones by 1990. How it works is simpler than you would think. First, there is an important difference between ‘noise-isolating’ and ‘noise cancelling.’ Noise-isolating is basically passive noise cancelling, which means the headphone shell is designed to be thick and completely encompass your ear to prevent noise from traveling through. Electronically it does nothing, it’s like putting your hands over your ears, it just blocks the sound. Active noise-cancelling requires some more components within the headphones. The headphones have a mic, or a number of mics, which picks up all the sound that it hears (that your ear would hear), but not the sound that the headphones are producing. Then there is a little processor that takes the signal from these microphones, and shifts them 180 degrees out of phase. What this means is, it takes the sound wave, the air pressure fluctuation, and inverts it so that the waves cancel each other out and you perceive no sound was ever made at all. This technology has existed for two decades and has now been implemented in a number of different ways. Some headphones always have active noise cancelling on, some have a switch on them to turn it off and on when you don’t need it, some just blare white noise to make it sound quitter (sort of like a library) when really they just make it louder overall even though it is easier to hear your music.

So when the box says ‘noise-cancelling’ make sure it has active noise cancelling with microphones, otherwise they are technically lying to you.

 

Let’s have a look at some real life products, and the ways that their marketing team bends the truth to sell you a pair of headphones.

 

http://www.beatsbydre.com/headphones/pro/beats-pro.html

“True noise reduction”

 

“Because Beats Pro headphones have heavily padded, pivoting ear cups, you get the noise cancelling effect without the need for power switches or batteries. It’s the real studio monitor experience in a headphone.”

So they say “true noise reduction” then go on to describe what noise isolation is.

http://www.engadget.com/products/monster-cable/beats-by-dr-dre/beats-pro/specs/

This shows that it in-fact does have active noise cancellation, which does require power from somewhere.  I don’t know why I had to look at an outside source to find any of this information in the first place.

http://store.apple.com/us/question/answers/readonly/whats-the-difference-between-pro-and-studio/Q2F9C9944JC4HDK2Y

Not a very valid source, but the confusion continues. Here it is explained that the beats studio have active noise cancelling, while the beats pro do not. Based on what beats says on their website, and the fact that the studio headphones require batteries and the pro do not, I am led to believe that the beats pro do not have active noise cancelling. Notice that they never SAID that they did, but they want you to believe that this lingo they created “true noise reduction” means the same as noise cancelling, which they use in the description of the feature.

http://www.beatsbydre.com/headphones/studio/beats-beatsstudio.html
notice the new model of studio beats comes with a charging cable, because active noise cancelling requires power. This is a really easy way to tell if you are getting active noise cancelling or not, since often they will use similar wording either way.

So why are the Beats Pro more expensive than the Beats Studio?

“Clear highs and deep lows”

“Beats Pro are made of steel and aluminum, giving you an interior sound platform more solid than most. That’s why you’ll feel the kind of bass that resonates deep in your chest when you play your music”

What?

No really, I have no idea what they are talking about, and I would consider myself well educated on audio. The headphones shell is made out of steel and aluminum. The shell has absolutely no effect on frequency response of the headphones. What is an “interior sound platform”? What does this term mean? Who knows, but I reiterate the makeup of the shell has nothing to do with audio quality.

Also, if it did, metals have very HIGH resonate frequencies, so making them out of metal materials will help reinforce the higher end of the frequency spectrum, not the bass that resonates deep in your chest. So even if this steel and aluminum was affecting the interior sound platform, which it doesn’t, it would not help the low frequencies, like they are saying.

So why are they more expensive? Because the materials to manufacture them are more expensive, which makes them also look more expensive. Is the difference in price between about a pound of plastic and metal $100?

All of these things are not my biggest problem with Beats. The problem is that they advertise their audio quality to be supreme. Well good audio quality is true audio. Ideally, a perfect set of headphones will perfectly reproduce the sound of the recording as it was mixed. The face that ‘Beats Audio’ does anything to alter the sound at all should tell you about their esteemed sound quality. Beat Audio puts all sound through equalization. Equalization is the altering of different frequency band volume levels in the overall sound, you may be familiar with simple EQ’s that tune the ‘high’ ‘mid’ and ‘low’ frequencies to your liking. This is what Beats Audio is doing, it is altering the sound that is coming into your ears to the way Beats thinks it should sound. Being the owner of an HTC phone from the era when Beats Audio was included in every model, I can hear first-hand what this mysterious EQ does. It makes the low end louder, and the overall volume higher when switched on. The thing is, this is what people THINK is good audio quality. Due to trends in popular music, the ‘bass’ has become the most important aspect of every speaker. Using their own proprietary EQ that you cannot turn off allows them to build off this belief without having to create larger speaker coils/diaphragms that can more accurately produce lower frequencies. Beats forces you to have a less true sound, which is what makes actual good audio quality. If you want true studio quality (true to the recorded sound), then don’t buy beats because you simply cannot obtain a true sound when it goes through an EQ.

I’ll leave Dr.Dre alone now. Beats are not the only ones who fill their product advertisements with meaningless garbage that doesn’t make any sense.

http://en-us.sennheiser.com/downloads/d3a25f7a03e97a4d2f9f48bc7354d7c7.pdf
This is a specification sheet that is supposed to tell you all the technical information about the headphones, for people like me. Notice that even this document has lots of pictures and focuses on the features without describing how they really work.

“Best-possible protection from outside noise (up to 90%)”
Really?

http://www.audio-technica.com/cms/headphones/939a5e9985fc5d2c/index.html
These say they get 95%. I guess best-possible does not mean actually the best.

“adaptive baffle damping”

Baffle damping is to prevent mechanical vibration, which isn’t a bad feature, but the word ’adaptive’ is what irks me. A quick google search reveals that this term is only used by Sennheiser on their own products. If I were to guess what the adaptive nature of the baffle damping is, it’s that it can baffle many different frequencies, preventing you form feeling vibration, depending on what sound is being produced. Again, not a bad feature, but this has nothing to do with the audio quality, like they infer it does in their first statement.

Those things being said, these headphones are much better than the beats just by the amount of extra components and features. I don’t know why a leader in headphone technology has to say deceptive things about their products on their own spec sheet, which shows that they are legit.

 

 

http://us.akg.com/akg-product-detail_us/k551wht.html

At least this has a very small spec section at the bottom of the page (labeled as “full specs”). To find the actual FULL spec sheet, it took a bit of navigating.

http://us.akg.com/tl_files/catalog//AKG/AKG/Spec%20sheet/Home/K%20551/Specification%20Sheet%20-%20K551%20%28English%29.pdf

“1-31/32” drivers”

“Powerful 1-31/32-inch (50-millimeter) drivers enable K551 reference-class headphones to do things that other headphones can only imagine. Music is rich and layered, while sound environments seemingly unfold before you no matter how loud you turn up the volume.”

Music is rich and layered. That really depends on the song don’t you think? A better way to say what they want to say would be that the headphones produce sounds at all frequencies very evenly, which allows you to hear the layers and richness in music.

“Real Image Engineering

Real Image Engineering is the science that fits an actual soundstage inside the space between your ears and the K551 headphones. With Real Image Engineering, sounds are huge and accurate, with an incredibly realistic sense of width, distance and depth.

Again, very cool feature, but very dependent on the audio you are putting into these bad boys. It won’t make a stereo MP3 file sound like you are in a magical realm where you are listening to the artist record right in front of you. If you are not sure what  stereo MP3 file is, its what you get form iTunes, Amazon, google play, Spotify, last.fm, pretty much every major music distributor uses a less demanding audio codec like mp3 (apple uses their own proprietary format that is very similar, but slightly better). What this means is that unless you are actually doing studio recording, or listening to something with surround sound, this feature does nothing. It’s a fancy way of saying “has 7.1 channels of surround sound.”

So what do you do? Even the legitimate good audio companies say superfluous crap to make you buy things, how can we believe anyone?

There are a few things you can believe, the specs. There are 4 key specifications that can tell you at least a little bit about what to actually expect from the headphones. They will always have some patented feature that they are trying to sell, but all headphones have these 4 properties in common and are defined somewhere on the products webpage/spec sheet/packaging.

Frequency Response (frequency range)

This is the frequencies that the headphones are capable of producing. Typical lower-end headphones cover 20Hz to 22000Hz. The average human can hear 20Hz to 20000Hz, and even less of this spectrum is used by musical sounds. Giving the range of frequencies that the speaker can physically produce is nice to know, but it doesn’t tell you anything about the harmonic makeup of the sound, which is what will actually determine the “trueness” of the sound.

http://www.jblpro.com/BackOffice/ProductAttachments/JBL_EON510.pdf

This is a spec sheet for a JBL speaker. On page 2 in the top left corer you see a frequency response graph. A perfectly true speaker would have a perfectly flat frequency response, but as you can see there is always some inconsistency due to the resonances of the physical components. THIS tells me what the frequency response is, not a range of frequencies that it at some level can produce. Since the headphones won’t even be using the ends of this spectrum most of the time anyway, it’s pretty useless to use a range of numbers as a gauge for sound quality. If you can find a frequency response graph (unlikely) for the headphones,  that will tell you what you really need to know.

Sensitivity

The sensitivity is easier to understand. The higher the sensitivity, the greater the change in volume per adjustment increment. So if you turn up the volume one notch on headphones with 100dB sensitivity, they will not be as loud as headphones with 101dB sensitivity. Typically having higher sensitivity is better, since it gives you a larger range of volume adjustment, but having sensitivity above about 105 will allow the headphones to operate at a volume that will (not can, will) damage your ears over time, so keep that in mind.

Impedance

The most useless of all of these specs, this is basically a ration of sound output to power input. Higher impedance (in ohms) means louder for less power. Higher impedance can be detrimental to the lifetime of the headphones if they have cheap components (see Skullcandy), but typically higher impedance is better because it is more energy efficient.

Maximum input power

This tells you the amount of power that the speakers will operate at. Again, higher is typically better, but this power is drawn from the device that is playing the music. If you have bad battery life on your music player, you might want lower input power.

So wait, none of these things actually tell me about sound quality? You are correct. Unless you find a frequency response graph, there is no way to know what will sound better. Ultimately that is the fundamental problem with trying to sell headphones, you have to sell a product that produces sound based on what people can see. If you over-complicate the information that you give about the product it will get lost in translation, so they keep it simple with flashy vocabulary and audio buzzwords that will appeal to the average consumer, without actually saying anything. What I want you to take away form this is that these companies are taking advantage of us as consumers. They know that we don’t know, they know we make decisions with our eyes, and they exploit this with the way they market their products. Audio quality is in the ear of the beholder, not in the words on the packaging, and without blind testing of two separate products it is impossible to distinguish which one has “better audio quality,” plus every person prefers their sound a certain way (see psycho acoustics post) so you get different opinions from different people. Just be sure you are getting a product by a manufacturer who has been distinguished in the industry and has features that you want. Good ‘sound quality’ means sound that is as close to the original waveform as possible, which then depends on the content, you feed into the headphones. Perhaps that is a topic for a different post.

 

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