What is headphone impedance and why does it matter?

1. Impedance

Impedance is a measure of how much resistance a device has to the electric current that flows through them. It is measured in ohms (Ω). In headphones it affects how loud and clear the headphones sound, as well as how well they work with different audio sources.

2. Input Power

Generally speaking, higher impedance headphones require more power to produce the same volume to that of lower impedance headphones. This means that they can handle higher levels of input without distorting the sound or damaging the drivers. Higher impedance headphones also tend to have a more balanced and detailed sound, especially with high frequencies.

Lower impedance headphones, on the other hand, are easier to drive and can reach higher volumes with less power. This makes them more suitable for portable devices, such as smartphones, tablets, and laptops, that have limited battery life and output. Lower impedance headphones also tend to have a more dynamic and punchy sound, especially in the low frequencies.

3. Choosing the right headphones

Choosing the right pair of headphones comes down largely to applications for use, the type of audio equipment being used, and personal preference.  Here are some general rules of thumb to help you make an informed decision:

If you mainly use your headphones with portable devices such as smartphones, tablets, and laptops, you should look for headphones with low impedance (less than 50 ohms). This will ensure that your headphones can get enough power and volume from your device without compromising the sound quality or battery life. For example:

• Sennheiser HD 200 PRO has an impedance of 32 ohms, and is not only great for monitoring, but can be used for casual listening too.
• Sennheiser IE100 Pro are professional in-ear monitors for use on stage and in studio. They have an impedance of 20 ohms.

If you mainly use headphones with high-end, professional audio equipment (headphone amplifiers, audio interfaces, etc) you might look for headphones with higher impedance (more than 100 ohms). This will ensure that your headphones can handle the high-quality input and deliver a more detailed and accurate sound. For example:

• Sennheiser HD 490 PRO has an impedance of 130 ohms, and is designed for critical listening and mixing in professional environments.

If you use your headphones with a variety of devices, both portable and stationary, you should perhaps look for headphones with moderate impedance (between 50 and 100 ohms). This will give you a good balance of performance and versatility, as your headphones will be able to adapt to different sources of audio without compromising on sound quality or volume. For example:

• Sennheiser HD 25, which has an impedance of 70 ohms and is designed for DJing, broadcasting, and recording applications.
• HD 300 Pro and HD280 are neutral, professional studio monitoring headphones rated at 64 ohms each, and are ideal in recording/studio applications.

4. Conclusion

Not every headphone is the same. Choosing the right headphone for the application not only comes down to how they look and sound, but also how they match to the equipment you will use them with. 

If you still need help choosing then please contact our support teams who will be happy to advise you further.