The Sadowsky Onboard Bass Preamp (4-Knob System) is a pre-wired system that offers the same control options and the legendary active preliminary. The preamp is designed for installation in most bits in the J-style with a control plate made of metal. With newer active models in the J-style with a side starting socket and a battery compartment, no `` `antifications are usually required. In passive instruments, the only required change is to lay the output socket to the side of the instrument and to create space for a battery. The control options are: volume � Pan (balance) � VTC (vintage tone control) � Treble / bass. The bass and H�hen-controls boost exclusively- turn the controls completely to the left you get a linear frequency response. The VTC controller works passively, the maximum set.
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