LR Baggs CTRL-X Control-X Preamp
The Ctrl-X onboard preamp combines traditional passive magnetics With piezo bridge pickups for immediate and effortless versatility. With the Ctrl-X, you can mix an acoustic piezo signal With your magnetic pickups Without active circuitry ruining the sound of your magnetics. Choose between magnetic pickups, magnetic/piezo blend or piezo pickups only With the flick of a switch.
Control-X Preamp: Installation Manual & User's Guide