Originally posted by anstratdubh1979:[..]
You can get that tone with Comp/Boost and Delay.
What did Edge have for the album? By then he had the MXR DynaComp Compressor, Boss FA-1 Bi-Fet (for boost)... He still had E-H Deluxe Memory Man during the making of the Unforgettable Fire album - for Delay. But it's also possible that he used the Korg SDD3000.
A lot of the tone definitely comes from the guitar used too. I think it's still a mystery as to what he used. Some think it was the White Falcon, some think it was a tele,some think it was his strat with the Dimarzio FS-1 or the Seymour Duncan Quarter Pounder, and some think (this is what I think) it was his LPC. You can see him using the LPC in windmill lane in the making of UF videos while they're doing overdubs, so I think he used the LPC.