In Reply to: Oh! TUBES! posted by Paul C. on July 25, 2001 at 13:34:57:
The "Thermionic" series references the name of the property that makes tubes work, "thermionic emission." The Thermionic Series is a line of speakers that has been specifically designed with tube amps in mind. They are high efficiency designs with minimal impedance fluxuation and bass alignments that are slightly overdamped, which tolerates high output impedance better. Most models of Pi Speakers could be described this way, but the Thermionic Series has speakers with these particular traits maximized.
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