Two from the Vault is a 4LP live album by the rock band the Grateful Dead. It was recorded at the Shrine Auditorium in Los Angeles, California on August 23 and 24, 1968. The event was left unreleased for nearly 25 years, before being mixed down from the original multi-track reels and released on Grateful Dead Records in 1992.

The concert was recorded on a then-state-of-the-art, one-inch 8-track tape machine that was supplied by the band’s record label, Warner Bros. The record company also insisted on supplying engineers who turned out to be unfamiliar with the close miking technique involved in recording rock music. Consequently, each of the eight tracks contained significant leakage from all of the other instruments in the band, resulting in severe phase cancellation problems.

Almost twenty-four years later, Don Pearson and producer Dan Healy solved this problem by employing a B&K 2032 Fast Fourier transform (FFT) digital spectrum analyzer to measure the delay in time between the different microphones, using the track of bassist Phil Lesh as the time centerpiece. The delay times were fed into a TC1280 stereo digital delay, which, along with careful mixing, resulted in a nearly perfect stereo image.