why can't i loop (w/dl-4) through my spider valve?
Who says you can't do this? You most definitely *can* do this. Just put the DL-4 into the effects loop of the SV and you're off to the races..
Be aware that the DL-4 is not designed to run in an effect loop and take "line level" input, so you will want to take the precautions listed in this FAQ to ensure you do not suffer an op-amp failure:
Line 6 Four Button/Stompbox Pedal FAQs
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