 |
Isolation |
|
• Loud, but not that loud.
• Open-backed design ruins isolation and leakage control.
• Use these in an indoor, private setting for optimal results. |
 |
Sound Quality |
Page 4 of 12 |
Comfort |
 |
Maximum Usable Volume (6.97)
What we found:
The DT 990s were capable of outputting about 107.26 decibels. This will be sufficient for most users, but we would've liked to see a slightly higher number. We award max points for 120dB or greater, since it's a very, very loud output and anything louder will ruin your ears.
What is maximum usable volume?
As you boost the volume of your playback, it will tend to get more and more distorted. Why? Because your headphones suck. Ideally, increasing the volume will increase just the volume and not the distortion. Most headphones can't do this, however, which is why we run this test.
How the test works:
For this test, we play back our trusty frequency sweep, each time boosting the volume. We keep doing this until we reach 3% distortion, which is when your playback will start sounding gross. If a set of headphones can reach 120dB without hitting 3% distortion, congratulations, they win. Any more than 120dB is pretty redundant, and is actually quite dangerous for your hearing. Since we like pretending we're your mom, we punish those nasty, hurtful headphones by not awarding them any extra points. For more on this test and our inappropriate maternal instincts, read this link.
Isolation (1.60)
What we found:
The DT 990s are open-backed headphones. See those vents on the back of the ear cups. Those are just for show; they let sound escape and enter. Why? To create a more open soundstage.
Open-backed headphones have terrible isolation.
How the Beyerdynamic DT 990 compares:
What is isolation?
The short answer: isolation refers to your headphones' ability to block out external noise. The slightly longer answer will begin after this "slightly longer answer" introduction, in order to allow the short answer people to flee the paragraph. Ok, now that those jerks aren't reading any more, allow us to elaborate. There are two types of isolation: active cancellation and passive isolation. You've probably heard of active cancellation, because it's a buzzword at the moment. Headphones with active cancellation use a microphone to listen to external sounds. They then use fancy computer chips to reverse the amplitude of this external noise and play it through the headphones. When a sound wave meets up with a sound wave of an inverse amplitude, both are negated. This is a great solution, but the technology isn't perfect yet. You'll likely get some noise as a result, and active-cancellers tend to only cancel out bass frequencies. Passive isolation is the brute force method. Plug up your ears with any old object and you'll have achieved passive isolation. Passive isolation doesn't block out much bass, but tends to block out more external noise overall.
How the test works:
Our isolation test has an ingeniously simple test. We put the headphones on HATS, then blast them with a bunch of noise. The trick? We know how much noise we're playing. We subtract the initial noise from the amount that HATS hears and we're left with the amount the headphones block out. You can find out more in this article.
Leakage (2.88)
What we found:
As we mentioned above, the DT 990s are open-backed headphones. They therefore leak like crazy as part of their design. If you are in a library, at the museum, or attending a wedding, you should refrain from blasting the volume on your DT 990s. Not only will you cause a scene with your buffoonery, but everyone will laugh at you for unironically listening to a techno remix of the Inspector Gadget theme song.
What is leakage?
Leakage, as it pertains to headphones, is the amout of sound that escapes into the world around you. If you have headphones that leak like crazy, those sitting near you will be able to hear whatever you're listening to. If you have headphones with low leakage, you can boost the volume very highly and those around you will be none the wiser.
How the test works:
For this test, we play a bunch of noise through the headphones, which HATS is wearing. We have a mic set up a few inches away that listens for any of this noise to escape. Now that we know exactly what's escaping, we get to do some math and assign a score.
|
