What is Sound Leakage? (and how to test and reduce it)

You might’ve heard about it or heard it in real life. Your headphones likely suffer from it to a degree.

It annoys most people.

What are we talking about?

Sound leakage—or music bleed and everything you need to know about.

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    What is Headphone Sound Leakage?

    Sound leakage (bleed) is the effect of music escaping from your headphones into the outside world. When others can hear your music, it bothers those that want silence and takes away from your sense of privacy.

    It’s more audible at higher volumes (high sound pressure level) and largely depends on the type of headphones. On-ear headphones usually leak more than over-ear headphones (but depends on ear cups).

    On the other hand, at low volume, it’s often impossible to hear.

    No headphones have perfect passive noise isolation (but in-ear headphones are usually the best).

    Therefore, all headphones “bleed” some of the music from the interior environment (your ears and inside of ear cups) to the exterior or outside world.

    Why headphones leak sound?

    Headphones leak sound because some of the air vibrations break through the ear cups and ear pads that are meant to stop it. The higher the volume, the more sound leakage occurs. It’s physically impossible to stop all sound with limited material used in creating a standard pair of headphones.

    While many modern headphones use thick sound-absorbing materials to improve sound isolation, there’s always some audio leakage present.

    So far, no headphone manufacturer managed to create headphones with no sound leakage.

    Sound is basically air pressure that moves air particles which our ears can sense.

    Max volume is a high pressure level that can lead to hearing loss.

    The sound travels from the starting point and extends all around it until it’s slowly diminished with range.

    You can block it prevent it from spreading, with physical objects from plastics, wood and sound-absorbing foam.

    Nonetheless, in the distance from your ears (listening to music with headphones) and a short range around you, some sound will always be audible.

    To block sound to inaudible levels, you’d have to use an uncomfortable amount of material which would make headphones cumbersome and useless.

    Why should you care about sound leakage in headphones?

    Headphone sound leakage is negative when you don’t want other people to hear your music or videos you’re watching (it can be embarrassing). Also, if the sound can leak out, it can break in too. Therefore ambient noise can ruin your listening experience.

    Would you like it if everybody around you, in the office or on the commute, would know what music you’re listening to?

    Having a sense of privacy in what you’re listening is important to most people.

    Sometimes we travel to the weird places of the internet just because we have nothing better to do. Imagine how embarrassing it would be if everybody knew what you are listening to.

    Get headphones with low sound bleed and keep your music to yourself.

    How to Test for Sound Leakage in Headphones?

    • The best way to test for sound leakage in your headphones is to borrow your friend.
    • Let him, or her wear the headphones (properly with a tight fit and correct eartips – if earphones).
    • Then play the music and increase the volume.
    • It’s best to test in a quiet room, and you’ll soon know when the headphones start to leak.

    You probably don’t have the necessary equipment to measure sound bleed objectively, so it’s best to rely on your senses.

    And when you’re testing, try different genres of music as some might leak more than others. Play with the volume and remember the leakage starting point.

    After you get a good sense of where is the critical point (if you find it) you can swap the roles and let your friend tell you what he or she thinks.

    Here’s an example of what we have in mind.

    How can you tell if your headphones are leaking sound?

    Apart from the test with your friend we mentioned above, you can also record the leakage with a microphone.

    • Set up the microphone to record (like a smartphone)
    • Put on the headphones
    • Play with volume
    • Listen to the recording

    Another way to tell if your headphones are leaking sound is to use another method to mimic sound isolation as if you were wearing them (for on-ear and over-ear headphones).

    You can use your hands, other parts of the body, or objects.

    While the results might not be as accurate, you’ll still be able to determine which headphones leak more sound.

    What type of headphones leaks the most?

    • Open-back headphones have the worst leakage due to open-to-air design that doesn’t block the air vibration.
    • Semi-open headphones are a close second, a bit better than fully open but still pass on a lot of music.
    • Closed-back headphones leak the least.

    Today, most headphones are closed-back since this is what most users prefer.

    open air headphones leak sound

    Open-back headphones leak the most (see the mesh on the earcups)

    Nonetheless, you can find great open-back headphones, especially for home use, where sound quality can be enjoyed in a peaceful environment.

    How Does Sound Leakage Affect Headphone Performance

    Headphones with high sound leakage (open-back, semi-open) have bigger and broader soundstage, which gives a better sense of spacious sound. This is why they’re preferred by many audiophiles but bleed the sound. On the other hand, low sound leakage headphones (closed-back) offer smaller soundstage but better privacy (keep the music to yourself).

    Sound leakage is connected to noise isolation.

    Passive noise isolation block sounds in and out.

    Note, isolation is not the same as noise cancelling, click here to learn the difference.

    Music escaping out is what’s also called sound leakage.

    Heavy “bleed” is not preferred by anybody, but if it brings better audio quality, many are willing to accept it.

    Because open headphones don’t block the music inside their ear cups, it sounds more natural and gives a better impression of coming from a different direction.

    When listening to orchestra music, you can hear the instrument positions quite well. It gives a feeling of listening to the music at a concert hall (instead of your home living room).

    On the other hand, closed headphones try to keep the air vibrations (sound) inside the ear cups, which alters what you hear in the end.

    Also, it hurts soundstage and positional accuracy. Everything sounds like it’s originating in the middle of your head.

    Why is Reducing Headphone Sound Leakage Important?

    Reducing sound leakage is essential if you care about your privacy and if you don’t want to bother others with your music. For example, it’s crucial you pick headphones with low leakage for office use because you don’t want to annoy your coworkers (it impacts focus).

    Working with open-back headphones and laptop

    Working with open-back headphones (like in the pic) will leak a lot of noise.

    You might have the experience of a coworker coming to the office with a pair of headphones.

    And then blasting loud music so everyone around could hear it.

    It probably wasn’t positively impacting your productivity.

    Background noise pollution in offices is generally not accepted.

    What can you do to reduce sound leakage in your headphones?

    You can change the ear pads for headphones where replaceable pads (with more isolation) are available. And, for in-ear headphones/earbuds you can put on memory-foam eartips which are substantially better at keeping the music in. Also, if the reason is structural damage, you have to repair or replace them.

    Apart from that, there isn’t much else you can do.

    Turning the volume down or wearing ear muffs over earbuds isn’t practical.

    Each pair of headphones comes with some leakage which you’ll simply have to accept.

    If better ear pads exist, you can replace them but don’t expect massive change. Open-back headphones will always leak sound.

    In contrast, with earphones, you can make the biggest difference with proper ear tips.

    Soft, squishy, foam ear tips are the best for the job.

    A lot of earbuds come with them in the package, and you can always buy them separately (but make sure to get the right size that fits on buds and your ear canal).

    Look at the manufacturer’s size guide to learn what diameter you should get for your in-ear headphones.

    Comply memory-foam tips are the most popular and known. Check them on Amazon.

    When is sound leakage too severe to repair?

    If your headphones suffer from structural damage that opened the cups/buds (you might’ve dropped them), then the only way to fix the leakage is to repair them. Which is often costly and isn’t economical. In this case, it’s best to get a new pair.

    Headphones with Least Sound Leakage

    What are the best headphones with low sound leakage?

    Because audio leakage is connected to how well the headphones isolate the music, the same headphones that have fantastic noise isolation also have the least “bleed.”

    You can find great passive noise isolating headphones in our guide below. They block all the sound coming in and going out.

    Click here for headphones with low sound leakage.

    What types of headphones have low audio bleed?

    Looking at acoustic design:

    • Open-back and semi-open headphones have high sound leakage
    • Closed-back headphones keep it in much better (low bleed, high isolation)

    Considering the type:

    • On-ear headphones tend to leak the most (with exceptions)
    • Over-ear headphones are about average (mostly depends on earpads and size)
    • In-ear headphones (or earbuds) leak the least, especially good with memory-foam eartips
    • Bone conduction headphones have high bleed due to different technology

    When picking headphones with low sound leakage, get closed-back headphones with thick earpads (if over-ear & on-ear) or in-ear headphones with memory-foam tips.

    Does Bone Conduction Produce Sound Leakage?

    Bone conduction produces noise leakage because sound vibrations travel through the bone and air. Some of the music is always transferred to the air, so others can hear it. Bone conduction headphones have higher than average bleed.

    What are The Best Bone Conduction Headphones?

    There’s quite a selection of bone-conducting headphones you can choose from.

    But the best are made by AfterShokz, a steady market leader in the category.

    These are popular headphones for running by many and offer optimal audio quality and durability.

    Click here for best bone conduction headphones.