As of May 2023, we no longer include frequency response measurements on USB sticks in the boxes of the HD 800S, HD 820, and HDV 820.
It may be possible to reprint older certificates, but not all records are available.
Why we stopped providing measurements
Headphones are directly coupled to the ear, which means sound perception differs from person to person. The sound you experience depends on your individual head shape, outer ear, and ear canal – standard measurements cannot predict how you will hear them, only the levels produced.
Additionally, production measurement equipment differs from head simulation devices, and frequency response is just one part of overall sound quality. Other important factors include:
- Distortion
- Openness
- Weight
- Angling
- Transducer surface area
The best way to judge sound quality is simply to listen.
What this means for you
You will no longer receive USB frequency response files with the affected models. However, you can still evaluate sound quality by listening to your headphones using trusted listening setups and guidance from our team.
How to evaluate sound for yourself
- Listen to reliable source material on familiar equipment.
- Use proper equipment, environment, and media suited to your headphones.
- Rely on your listening impressions rather than a single measurement.
Still have questions?
Contact our support team for guidance on setup, tuning, or recommended listening practices.