Prior to building, I was an endorser of Bee Basses. Fred Bolton (Bee basses owner/builder) had a friend making these preamps for his basses. His name is Dave McKeen. When I received my first Bee bass, I couldn’t believe my ears. It was like pulling the blanket off the cab! When I began building, Dave was one of the first people I called. We moved a few center frequencies around. The bass is centered at 40hz, mids at 560hz and treble at just under 7khz. The thing that sets this apart from other 3 bands is the musicality you will experience. Set flat, there is an overall 3db of gain which causes your signal to hit the amp with more clarity. It’s like a souped up version of what your bass sounds like passive. Each band has a full 18db worth of boost or cut. It is extremely powerful. Something I enjoy about this preamp is how the bass boost doesn’t get out of control. Things stay tight and focused. These are top shelf, hand made by Dave and in extremely limited supply.