Abstract: Audio input tubes and power output tubes in a vacuum tube amplifier are powered and controlled by solid state controllers. The solid state controllers sample incoming audio and anticipate and apply changes and biases in grid and plate voltages before the audio signals arrive in the power output tubes. Any mains voltage is filtered, regulated and converted to a standard voltage which is converted to plural DC voltages that are applied to sensors, tube cathode heaters, grids and plates and are varied on screen grids and plates with stepped increases and autobias. The solid state components have sensors and feedback to control voltages. Sensed overvoltages fold back power to the solid state devices and heaters, screens and plates to provide uninterrupted amplification without endangering the tubes or components.

Abstract: Segmental daisy chain power connectors for electric powered musical equipment have short two wire insulated power cords with first and second push-in barrel or telephone-type male connectors at first and second ends and push-in barrel or telephone-type female receivers at second ends. The receivers are axially aligned with or perpendicular to the second push-in male connectors at the second ends of the power cords. The push-in connectors have internal insulated connectors for connecting to pins in receivers in the cords and in receiver power connections in the musical equipment.

Abstract: Musical instrument effects pedals are powered from adjacent pedals by providing electrical connectors between adjacent pedals and by providing tip-ring-sleeve jacks in the pedals and three wire connectors with tip-ring-sleeve connectors, which carry sound signals from an instrument through sequential pedals and electrical power in an opposite direction to the pedals.