Strawberry Fields Forever is two completely different recordings joined roughly a minute in, one of them slowed and the other sped up until they met. That is why nothing on it sounds quite natural, guitars included.
What makes the tone. Dark, slightly detuned-sounding and swimming in reverb, because the tape speed was altered after the fact. The Mellotron flutes carry the melody; the guitars are a low, blurred presence underneath.
The analogue recipe. Clean guitar, tone well back, into a plate reverb with a long tail. If you want the swimming quality, a slow, deep chorus or a pitch shift of a few cents against a dry signal gets close.
On a Boss GT-100 / GT-1000 / GX-100. A clean model with the treble down, a detune or slow chorus block, and a long hall reverb. A pitch block set a few cents flat against the dry signal is the closest thing to varispeed on a modeller.
On a Kemper. A dark clean profile, detune block, long reverb. Aim for unsettled rather than clean - the record's charm is that it never quite sits still.
Done for you. The Soulster Tonebook for fans of The Beatles → has the chords, capo positions, tempos and dialled-in settings for this one.
Frame the song. The "Strawberry Fields Forever" Paperback print → and the Studio Life t-shirt → carry the same song. Also on the Practice print → and the Studio print →.
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