Dave's Process for audio extraction for releases:
http://audiophilereview.com/analog/plangent---a-better-way-to-transfer-analog-tape.html
Time consuming but worth it.
Quote:
I've used Plangent Processes on a variety of projects for the Grateful Dead on older 16 track tapes as well as 2-track 7.5 ips material. The benefits of using the Plangent Process were added imaging, and outstanding clarity of the audio and pitch solidification...while keeping the original analog warmth.