I have seen some good headphones from Sennheiser before, such as the Sports headphones, the Wireless ones, and the PXC 360.

This is the Sennheiser 500 series of high-end headphones that include the HD598, HD558, and HD518. The HD598 includes a frequency response of 123 to 38,500 Hertz, the HD558 is 15 to 28,000 Hertz, and the HD518 has 14 to 26,000 Hertz.

I don’t have any word on pricing or availability and it has a compressed cellulose fleece to reduce total harmonic distortion to below 0.1 percent.

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