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Active gain boost question

Sunsett

Member
Joined
Oct 12, 2023
Messages
15
Location
Cali

Hey folks,
Normally I’d just pick up the phone, but it’s Saturday and EBMM is closed.
Q: re active gain boost on L4…does plugging an instrument cable into the jack pull juice from the 9v battery like an an active pup set up would?
TIA
 
Yes. Plugging the cable turns the circuit on, draining power from battery.
The stereo jack connector acts like a power switch:

Cable plugged = on
Cable unplugged= off
 
Welcome! :)
You can see how it works here, in attached document.

The boost should be factory set to +12dB, but it can be adjusted with internal trimpot up to +20dB (I didn't on the Luke III, since it could be too much...).
 

Attachments

Thanks for the welcome and the schematic. I have the gain boost set 1/8 turn from full. It’s perfect for L4>2i2>Reaper>NeuralDSP plugin>Adam7ax

But the live rigs could be another story. I’ll be test driving those setups shortly
 
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