I just bought a mesa dual rectifier, let me first say that this is by far the best amp i've ever played. I want to know how to properly use the effects loop with my hardwire delay, reverb, and big muff pi
As a general "rule" time based effects like the delay and reverb go in the loop, and the bif muff in front.
G.A.S. Afflicted
Since, generally, you want to delay and reverb your distorted sound rather than distort your delays/reverbs/other time based or modulation effects, you somehow have to chuck in those effects after the gain stages.

Hence, the fx loop provides an "out" from the preamp (where the gain happens) and back into the poweramp (where, unless at high volumes) there isn't as much gain.
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you put a cable coming out of the FX loop send jack at the back run your echo and delay effects through in whatever order you want then connect them back to the Return jack at the back. it should tell you in the manual how you do it....
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