The MPX G2 is advertized in such a way that it propagates a common misconception, or common limited thinking. The ad headline declares that the processor is set up to be placed "in both possible places -- before the amp, or in the amp's effects loop". But this spreads the misconception that leads people to loathe effects: the idea that there are only two possible placements for time effects, both which are before the saturating power tubes. This neglects the only sonically clear approach, the third alternative: the clearest tone when combining heavy power-stage saturation with heavy time fx (such as echo) requires putting echo entirely after the cranked tube power amp, just like you need to put echo after a distortion box.
This processor *can* be used even in a better way than the designers and marketers envisioned. The key feature is that the processor has a clean division into section A and section B. So you could do the following (which is in fact the best, clearest-sounding approach):
The way the processor is marketed is for this chain (which is in fact the medium-good approach):
The ad implies that that is better than this chain (which is in fact the muddiest sounding, or most limiting):
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