In 1991, Sennheiser introduced the electrostatic Orpheus HE90. The Orpheus system was Sennheiser’s attempt to show that they could produce a true audiophile headphone system that was able to compete with the best. Sennheiser positioned this system as "the ultimate in reference sound reproduction". The Orpheus HE90 remains one of Sennheiser's most highly praised headphone models.
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