ormances by famous artists.<sup id="cite_ref-williamson_1-3" class="reference"><a href="#cite_note-williamson-1"><span>[</span>1<span>]</span></a></sup> This led Paul &amp; Kerr to form DB Plus Digital Services, an independent mastering studio which operated in New York City from 1987 to 2009.<sup id="cite_ref-littwin_3-1" class="reference"><a href="#cite_note-littwin-3"><span>[</span>3<span>]</span></a></sup> In 2010, he became Chief Mastering Engineer at <a rel="nofollow" class="external text" href="http: