DigiTech Ventura Vibe Owner's Manual page 7

Amplifier Effects Loop Setup
Harman
FX SND FX RTN
Power Supply
Amp
OUT 1 (MONO) IN 1 (MONO)
OUT
Other Effects
IN
Use only unbalanced TS instrument cables for audio connections.
Optional
NOTE: If the amp effects loop has a mix control, set the mix to 100% full wet.
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