fixing SENNHEISER Amperior or HD25 HEADPHONE driver - YouTube
Sennheiser HD25 Plus Headphones — DJ TechTools
Sennheiser HD 25 Light New Version Review | headphonecheck.com
HD25-1 Driver repair experiment – CustomCans.co.uk Custom Headphone Blog
Amazon.com: Sennheiser HD 800 S Over-the-Ear Audiophile Reference Headphones - Ring Radiator Drivers With Open-Back Earcups, Includes Balanced Cable, 2-Year Warranty (Black) : Electronics