Sony have released a new type of headphone that has a separate bass 'duct', a tube that is inserted into the ear canal, and external speakers for the mid- and high- frequencies. The PFR-V1 headphones will be available for retail sale in the US in April. The reason for doing this is to provide a more natural sound rather than the 'in the head' sound from most headphones. Images of the headphones can be viewed on Sony's Japan web site.