<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">ondes Martenot</topic></authority><related type="broader"><topic>electronic keyboards</topic></related><variant type="other"><topic>ondes musicales</topic></variant> <note xml:lang="en"><![CDATA[ Monophonic, nonimitative electronic instruments, invented by Maurice Martenot in 1928. The tone is generated by the heterodyne action between a fixed and a variable radio-frequency oscillator, the latter being controlled by a seven-octave keyboard and the relative proximity of the player's hand to a horizontally stretched cord. ]]></note></mads>