Autechre have shared Warp Tapes 89-93 as a free download. 

The two-part mix is made of previously unreleased music composed by the UK duo between 1989 to 1993. It was broadcast for the first time over the weekend on NTS as part of Warp’s three-day takeover in celebration of its 30th anniversary

You can download the files via the Bleep store here, at the bottom of the page, or directly here.