<?xml version="1.0" encoding="utf-8"?><metadata xmlns:dc="http://purl.org/dc/elements/1.1/"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dcterms="http://purl.org/dc/terms/"><dc:title xml:lang="en">vacuum tubes</dc:title><dc:identifier>http://AATesaurus.cultura.gencat.cat/aat/getty_en?tema=31346865</dc:identifier><dc:language>en</dc:language><dc:publisher xml:lang="en">Getty Institute</dc:publisher><dcterms:created>2026-03-30 20:33:33</dcterms:created><dcterms:isPartOf xsi:type="dcterms:URI">http://AATesaurus.cultura.gencat.cat/aat/getty_en</dcterms:isPartOf><dcterms:isPartOf xml:lang="en">Tesaurus d&apos;Art i Arquitectura</dcterms:isPartOf><dc:format>text/html</dc:format> <dcterms:alternative xml:lang="en">vacuum tube</dcterms:alternative> <dcterms:alternative xml:lang="en">vacuum valve</dcterms:alternative> <dcterms:alternative xml:lang="en">tube, vacuum</dcterms:alternative> <dcterms:alternative xml:lang="en">vacuum-tubes</dcterms:alternative> <dc:description xml:lang="en"><![CDATA[ A type of electron tube that is housed within an evacuated glass bulb, used in electronic circuitry to control electron flow in the applications of current amplification, rectification, etc. Used extensively in common electronic devices until the advent of transistors. They remain in use in certain applications such as audio amplification where they retain a cult status among audiophiles due to audible properties of even-order harmonic distortion, particularly when overdriven. ]]></dc:description></metadata>