The OBEL set up guitar sends the signal from the guitar to the effects loop, back to the guitar, thru the main volume, and back out to the amplifier. A Y cable and mono send from the guitar to the amp can be used, the breakout box simply acts as a 'hub' to plug all the cables from the guitar into one location, and can be mounted on the pedal board. It's just a more solid and tidy solution than the Y cable, in my estimation.
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