7 ANC headphones tested: Which has the best noise cancelling?

Headphones with noise cancelling save us from noise on the train and from colleagues chatting away in the office. Just as everyone's hearing is different, every pair of headphones is different. Subjectively, one model filters out noise better than the other. However, there is a way to objectively measure active noise cancelling. I turn to the sound specialists at Rocket Science.

The company Rocket Science is not tinkering with the conquest of Mars, but with acoustics. That's why they are the right people to test and measure active noise-cancelling headphones. I give the team seven headphones. We selected them together and based on sales figures; these are the headphones that have been bought the most on digitec in the last three months. They include expensive and inexpensive headphones. What they have in common is that they are all over-ear models and have active noise cancelling.

The test devices

From inexpensive, older models to the latest high-end models, everything is represented in this test and is a colourful mix.

Headphones

Bose QuietComfort 35 II

ANC, 20 h, Wireless

2036

Headphones

Bose Headphones 700

ANC, 20 h, Wireless

828

Headphones

Sennheiser Momentum 3

ANC, 17 h, Wireless

204

Headphones

Sennheiser PXC 550-II

ANC, 20 h, Wireless

126

Headphones

Sony WH-1000XM3

ANC, 30 h, Cable

2452

Headphones

Microsoft Surface Headphones 2

ANC, 20 h, Wireless

137

Headphones

Returned & Tested

EUR221,47 currently EUR240,73 new

Beats Studio3

ANC, 22 h, Wireless

251

You can compare the individual specifications of the headphones at this link.

Measure the headphones with the noise analyser

Four noise experts from Rocket Science take on the task of measuring headphones. Nele, Nino, Manu and Philippe want to find out how much and how well the headphones make external noise disappear. The team uses various test scenarios to measure the quality of the noise cancelling: they build a diffuse field with a decahedron loudspeaker and a Fostex subwoofer. They use pink noise as the interference signal. Pink noise is often present in everyday life and covers a broad frequency spectrum. It is therefore suitable for measurements.

The team uses an artificial head for the measurements. The head - which the team calls the Noise-Kanzler - has microphones built into its "ears" that measure noise signals. The exact measurement setup, the software used and how the team measures can be found in the article below.

The result: objective measurement

Noise cancelling is basically divided into two categories: active and passive. Passive refers to the part that headphones placed over your ears seal off anyway. Active cancelling, on the other hand, is the cancellation of noise by means of anti-noise. Rocket Science measures the quality of purely active noise cancelling by subtracting the separately measured effect of passive isolation from the measurement.

The image below shows the curves of the tested models. The higher up the curve, the better the noise reduction - the figure shows the noise reduction as a function of frequency. So the higher the value on the vertical axis (or the Y-axis), the better the ANC performance of the headphones.

At higher frequencies (i.e. in the right third of the diagram), the reduction is significantly lower. High-pitched sounds are much more difficult to reduce with active noise cancelling than low-pitched sounds. They generate much smaller and faster waves, which is why it is technically difficult or even impossible to produce anti-noise waves for them. The headphones reach their technical limits at high frequencies with active noise cancelling.

You can see the graphic with this link in large view.

Attention: Now it gets a bit technical, but the information is important. The team uses ⅓-octave smoothing to better distinguish the curves. This means that they summarise several frequency ranges, as the diagram would otherwise be unreadable. The two vertical dashed lines show which frequency band the team uses to measure the noise level. Put simply: the range from low tones (frequencies) to higher tones that was measured. The team chose the frequency range from 50 to 2,000 Hz because noise cancelling works effectively in this range. ANC can hardly be measured correctly below 50 Hz - even in laboratories, inaccuracies occur here because too many interfering signals influence the measurement. From 2,000 Hz, the ANC of the headphones no longer works.

The diagram shows that the Sony WH-1000XM3 headphones (the yellow line) have the most effective cancelling. Compared to the other headphones, it has a weaker reduction at higher frequencies. Otherwise it is at the top. In second place are the Sennheiser PXC 550-II and the Bose Headphones 700, which also show exactly the same value in absolute figures.

The following graphic makes the differences even clearer.

The ranking shows the reduction in decibels in the frequency band from 50 Hz to 2,000 Hz - this is the range of the two dashed lines in the line graph. The labelling dB(A) stands for the sound weighting with an A filter. In simple terms, the sound weighting refers to the volume in decibels. In other words, a reduction of 10 dB(A) is considered half as loud in this case.

In other words, this means that with the second-worst model, the Sennheiser Momentum 3, you will hear almost twice as much noise as with the Sony WH-1000XM3. But it's even worse with the Beats Studio 3.

The effective figures in dB (A) look like this:

The result: subjective perception

In addition to the scientific measurement of the headphones, the team also tested the headphones on their own heads; audio experts Nele, Nino, Manu and Philippe wore the headphones on the train and in the office for two months.

Here is their subjective evaluation:

The thing that amazes me the most is that several team members got nauseous with the Bose QuietComfort 35 II. I used to hear about this from time to time when ANC headphones were brand new. I myself have this Bose model as office headphones and have never had any problems.

How come the subjective perception differs from the objective one in some cases? Although the Sony headphones reduce noise significantly better, the noise experts find the Bose Headphones 700 better. Microsoft and Sennheiser also swapped places in the subjective evaluation. Manu explains this to me using psychoacoustics: "We subconsciously perceive some things more strongly than others. High-pitched sounds tend to be more unpleasant for many people than low-pitched sounds. The Bose Headphones 700 cancels much better in the higher ranges than the Sony headphones. The team therefore found the Bose headphones more pleasant in the subjective evaluation than the pure, objective figures showed. The Sony WH-1000XM3 cancels more effectively in absolute terms, but it lets through more in the frequencies that are unpleasant for people.

At least the team agrees on one thing: the Beats are the worst headphones in the test - which is also supported by the objective measurements.

An audibly good collaboration

Even after this test, I am maintaining my collaboration with Rocket Science. The audio nerds have created recordings that use train noises and restaurant recordings to show how strong the ANC of headphones works. You can then hear what ANC filters out and what it doesn't. If you don't want to miss any of these articles, follow me as the author.