<?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">acoustic couplers</topic></authority><related type="broader"><topic>data connectors</topic></related><variant type="other"><topic>acoustic coupler</topic></variant><variant type="other"><topic>couplers, acoustic</topic></variant> <note xml:lang="en"><![CDATA[ Modems that connect to telephone systems and convert digital data into sound signals, which are then transmitted through telephone lines. Historically, for acoustic couplers to connect to telephone systems, telephone handsets would rest in soundproof enclosures which have loudspeakers and microphones that are close to the earpieces and mouthpieces of the phone handsets.  ]]></note></mads>