Isolation describes how well a pair of headphones keeps outside sounds out and your audio in. That means reducing ambient noise that could interfere with your listening experience, while also minimizing leakage so that your music or calls don't distract the people around you.
Good isolation is especially important in loud environments, like trains or airplanes, where external noise can easily mask quieter details in your audio. It also matters in shared spaces like open offices, where poorly isolated headphones can leak enough sound to bother others nearby.
The Isolation section of our reviews comprises four parts: Noise Isolation - Full Range, Noise Isolation - Common Scenarios, Leakage, Noise Isolation - Voice Handling, and ANC (Active Noise Cancelling) Wind Handling. You can find explanations of each of these tests below.
Test results
Our Tests
Noise Isolation - Full Range
- 100.0%Overall Attenuation
Noise Isolation - Full Range measures how well a pair of headphones blocks out ambient noise across the entire audible range, from 20Hz to 20kHz. We play calibrated pink noise through a speaker setup inside our test chamber and record how much of that sound is picked up by a microphone inside the ear simulator while the headphones are worn. This is done once with no headphones on (as a baseline) and again with the headphones mounted normally, with ANC off and on (if available). We then subtract the results to generate an isolation curve that shows how much noise is attenuated at each frequency. This helps identify whether the headphones block low-end rumbles, mid-range voices, or high-frequency whirs. Both passive and active components of isolation are captured in this test.
You can learn more about this test.
Noise Isolation - Common Scenarios
- 10.0%Airplane Noise Attenuation
- 10.0%Office Noise Attenuation
- 10.0%Street Noise Attenuation
Noise Isolation - Common Scenarios measures how well headphones block out noise in everyday environments. Instead of a pink noise source, we use recordings of everyday scenarios sourced from the European Telecommunications Standards Institute (ETSI). The three sources we've chosen are Airplane Noise, Office Noise, and Street Noise. Each of these reflects a common place where people use headphones, and each presents different challenges to headphone noise isolation, from low-rumbling plane engines to chatty coworkers and noisy street activity.
Like in our full-range test, we first measure the response without any headphones on our test rig, before measuring with both ANC off and on (if supported) to show how effectively the headphones reduce these specific types of noise. This test gives a more practical, real-world view of noise isolation performance.
You can learn more about this test.
Leakage
Leakage measures how much audio escapes from the headphones and can be heard by people nearby. It's important if you often use your headphones in shared spaces and don't want to disturb the people around you. Some headphones, like open-backs, leak a lot of audio by design, while others, like closed-backs, don't, because they're meant to be used in busy places like cafes and trains.
After calibrating the headphones using band-passed pink noise, we measure leakage by playing a sine sweep through the headphones and recording the sound that escapes using a microphone placed 0.5 ft from the dummy head at ear level. We take five measurements per ear, re-seating the headphones each time. The results are averaged across all 10 passes, limited to the 100Hz–20kHz range, and adjusted by -6 dB to simulate leakage at a 1 ft distance.
You can learn more about our leakage test.
Noise Isolation - Voice Handling
If you often wear headphones in places like offices, cafés, or grocery stores, you'll likely hear people talking around you. Noise Isolation - Voice Handling measures how well a pair of headphones blocks out human speech in noisy environments. We play back four separate voice samples (two male, two female) from Peter Kabal's Telecommunications & Signal Processing Laboratory Speech Database, and then record how well the headphones block out the different voices. We use this test to assess how well the headphones attenuate real-world conversations, with ANC enabled if available, but we don't score it because some people specifically want to hear voices while having other ambient noise around them blocked out. You'll want to listen to the audio samples provided in this section of each review to understand how well a pair of headphones blocks out human speech.
ANC Wind Handling
ANC Wind Handling evaluates how well a pair of headphones' active noise cancelling (ANC) system deals with wind, which can sometimes cause unwanted rumble or distortion. Obviously, we only perform this test if the headphones have an ANC system; if the headphones have a wind noise reduction feature, we activate it. Instead of a noise sample, this test uses an electric fan placed 30 cm from the test head. We take three measurements with the fan positioned at different angles (0°, 90°, and 180°) to simulate wind from various directions. Wind noise generally has a flat response in the low-to-mid range, up to around 300Hz, before tapering off at higher frequencies, so deviations are easy to see on our graph. That said, we don't score this test, so it's worth listening to the audio samples we provide in each review to get a sense for how a pair of headphones performs in windy conditions.
Conclusion
Isolation describes a pair of headphones' ability to block ambient noise and prevent audio leakage. Noise isolation is important in loud environments, as it will stop ambient noise or chatty coworkers from disturbing your listening experience. Leakage is important if you often use your headphones in shared spaces and want to ensure your audio remains private. Headphones with ANC features can often make buzzy noises if you're in a windy space, so we also check how ANC functions perform in windy environments.
Recent Updates
- 08-05-2025: We updated this article to bring it into line with our latest test benches.
