SR300e Bass Guitar with Powerspan pickups, three position mini toggle switch of which in this matter would concern the "Power Tap" position on the switch, (in the direction of the treble knob). As of this posting there has been no clear answer as to the mechanical functionality for the "Power Tap" selection. There have been suggestions as to what the true purpose or use for the selection for instance, "A BIOS program incorporated into the board itself as an effect". It just so happens as of this posting I have at my disposal a 2017 Ibanez SDGR-300E (I will not note in what color tone burst) and have put some man hours into getting to know it, that includes the Coil Tap function. Here is my "two cents" as to what the Power tap selection does mechanically/electorally when engaged. The Neck Pickup, Bridge pickup have been tapped (Switched) into single coil. The humbuck pickup coils are NO LONGER RUNNING IN PARALLEL (No longer true humbuck). In essence the pickups through the throwing of a switch become stacked single coils. When tested it was found that in power tap mode all pickup poles are indeed hot with some discernible pink noise when active. As to the other selection modes on the switch center is humbuck (No noise), the diction of the bridge pickup is the single coil mode of which when active produces the same pink noise as found in the power tap mode however only half of the poles are hot (Tested using screw driver directly on poles). Of course the center switch position (humbuck) all poles are hot and no discernible noise. when active, this with the EQ and pickup panpot zeroed out. Thoughts.