Headphone burn-in isn’t real

Despite the fact that I’m supposed to keep you reading for as long as I can, if you just clicked this link and internalized the title: you’ve absorbed everything you need to know. Seriously. Burn-in isn’t a concern for new headphones.

This is probably one of the most popular audio myths of all time, so there’s going to be a large segment of audiophiles who swear up and down that this is a make-or-break part of the headphone experience. It’s not, but like any good myth, it’s centered around a kernel of truth. A teeny, tiny, almost imperceptible kernel of truth.

So far, all the tests performed by various outlets online haven’t yet found objective data to support the idea that headphone guts actually change audibly over certain periods of time. Many manufacturers won’t comment on this phenomenon, or if they do: they shy away from telling audiophiles that they’re wrong.

Editor’s note: this article was updated April 21, 2020 to reflect manufacturer input on the issue.

The “burn-in” myth

The popular belief that you need to “burn-in” a set of headphones with hours of loud sample sounds like pink noise before they sound the best is just that: a myth. It’s partially true, but the myth states that the component that needs breaking in is the speaker element and its housing. The idea is pretty straightforward—the materials headphones are made out of will lose their rigidity over time, as it’s subjected to repeated force and sustained heat. Such a loss of rigidity allegedly makes it easier for the speaker element to move faster, resulting in better performance.

Now, that’s almost true: your headphones’ drivers and housings will lose rigidity over time, but it won’t cause an audible change in the measured performance of the headphones—at least, not for the better. While it’s true that larger loudspeaker drivers see larger amounts of material change over time (specifically, in the flexing part of the speaker element called the “surround”), the amount of use it would take to change the sound quality in a measurable way for headphones is ridiculous. In fact, much of the objective “evidence” for this phenomenon is shown on charts with a scale of 1dB or less. You can’t hear that.

Headphone burn-in isn't real: Black and white image of car manufacturing plant.

Flickr user autohistorian What’s done in a manufacturing plant doesn’t necessarily happen again after you purchase the product.

The practice of “burning in” speaker components stems from a simple quality assurance test performed in some manufacturing plants where they run the components for a period of time to see if the headphone drivers hold up under sustained use. The idea is, if the performance changes or degrades after that period of time: it’s a broken set of headphones. That makes sense—they do this for cars, cameras, and other machines, so why not headphones?

A change in sound that’s dramatic enough for you to hear it is cause for concern. If your headphones change in sound over a short period of time like 50 hours, do the materials magically stop losing rigidity? Nope. A loss of rigidity in speaker materials would also mean that the speaker would take longer to stop moving. That would mean ringing, echoes, and increased noise. This explanation of “burn-in” doesn’t quite cut it.

An expert opinion

My personal hunch regarding burn-in improving audio is twofold:

  1. Because we tend to believe what we’re told by our friends, confirmation bias is at work here
  2. The fit of most headphones changes over time.

To the first point, it’s an argument that’s been hashed out to death. However, even if you control for confirmation bias, some users still report an improved sound after a certain listening period. I’m very annoyed that this is often counted as evidence of burn-in, because the second point is almost never addressed.

If I sound like a crank, I am—but you should listen to me. For those of you who don’t know, I tested audio products for USAToday for over 5 years. I used a Type 4128-C Head and Torso simulator, along with state of the art measurement hardware, and industry-standard analysis software from Listen, Inc. I logged thousands of hours testing headphones on that fixture, and I learned a lot about the nature of objectively testing audio in that time.

Headphones require a seal in order to perform their best, and a poor fit will wreck bass reproduction, and increase noise and leakage.

Now that we test headphones in a similar fashion here at SoundGuys, the thing that causes us the most grief, the most annoyance, and the most botched tests is how even slight variations in fit alter what reaches your ears to a gigantic degree. It’s pretty incredible, really. Headphones require a seal in order to perform their best, and a poor fit will wreck bass reproduction, and increase noise and leakage. When we test headphones that aren’t able to fit correctly because the foam is too stiff—and therefore wouldn’t form to the head—the readouts suffer immensely. I hate testing on-ear headphones, because it’s unbelievably difficult to get an acceptable measurement without long periods of trial and error. With this in mind, let me paint you a word picture about what might be going on here.

Earpads are less durable than you think

While it seems like an obvious thing to say that the fit changes after use, that’s the main reason why so many on and over-ear headphones appear to “burn in.” Think of it this way: foam, fabric, and plastic is easier to deform than metal, right? So, why is it so incredible to believe that a set of headphones finally contorting its padding to your head and creating a better seal is the culprit behind headphones sounding better instead of burn-in?

Ever put a butt-print in your couch that doesn’t go away because you sit in it every day? This is exactly the same thing.

The reason is because cushion material in your headphones’ earpads is a form of viscoelastic foam. Viscoelastic foam has a fun property called “relaxation” where, over time, it becomes less and less able to hold its original shape or resist force than it used. Ever put a butt-print in your couch that doesn’t go away because you sit in it every day? This is exactly the same thing. Relaxation can be accelerated by heat and is one of the reasons memory foam mattresses get less firm the warmer they are. This happens faster with cheaper padding like what’s in your headphones.

A set of headphones with relaxed ear pads will fit your head better, simply because it’s less capable of resisting your noggin’s natural contours. A better fit means a better seal, and not only will isolation be far greater, but the headphones will sound much better too—as you can ensure everything the headphones are pumping out actually reach your ears and not the air around you. Given that most of the hours I spent testing were wasted on trying to get a good fit on that damned dummy head: a good fit is the most important thing when it comes to headphones.

Headphone burn-in isn't real: A chart showing the frequency response of a set of headphones that fit well.

Here we see emphasized bass, fairly even mids, and high harmonic notes are a little wonky, but not unusual.

I don’t expect you to just blindly trust me, so take this example. I acquired a test head and used a set of over-ear headphones to test frequency response. First, I took a measurement at a target of 84dB like normal, then I put glasses on the head like I would a human being, and measured again. The headphones stayed put, and I used painter’s tape to guide positioning.

So these headphones are fairly bassy (pink), and said bass notes are louder than the green mids. This is the most important part of most music, so we’re focusing on that left part of the chart for now. This chart will serve as our control: what a good seal will give you. But let’s see what happens when the variable of glasses makes your headphones have an imperfect seal at the exact same position.

Headphone burn-in isn't real: A frequency response chart showing the effect of eyeglasses on measured results and fit.

An imperfect seal on your headphones makes music sound far worse than it should.

Yikes. That imperfect fit dropped those bass notes down from 10-20dB below their original reading. To your ears, those notes will sound a half to one quarter as loud as they would with a perfect fit. That’s a huge, super-noticeable change in audio quality. While the changes in ear pads from brand new to broken-in won’t be this dramatic in most cases, it’s definitely something that could alter your listening experience—because it measurably does. Keep in mind, this measurement is only a couple millimeters of “broken” seal here.

Headphone burn-in isn't real: A sample frequency response chart showing how wearing glasses affects audio quality.

Here’s a look at the above two charts compared. Control in color, variable in gray.

If we look at the charts stacked on top of each other, you can see the difference more clearly. Keep in mind, this isn’t even an extreme example, just a common one. Over time, the viscoelastic foam will stop resisting so much against the glasses and your head, bringing the sound ever closer to that control reading. The more you use your headphones, the better they’ll sound. This is a much larger difference in sound than 1dB here or there by alleged burn-in.

What you should do

Instead of burning in your headphones by playing pink noise on repeat for 50 hours, just start using them like a normal person. Burn-in is pseudoscientific at best, and breaking in your earpads is going to have a much more pronounced effect on your music—and the only way to do that is to use your headphones.

You bought those headphones to enjoy, so go do it already!

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