It's rare for a product to go largely unchanged for more than 25 years, but Koss' PortaPro headphones have maintained the same design since 1984. In my latest blog post, I take a closer look at the PortaPros and discover why they've endured the test of time.
News: The sweet sound of Koss' PortaPro headphones
News: The sweet sound of Koss' PortaPro headphones