An x-ray source can include a housing with material with an atomic number of ≥42 and a thermal conductivity of ≥3 W/(m*K) to assist in removing heat from the x-ray source and to block x-rays emitted in undesirable directions. An x-ray source can include a shell that is electrically conductive and that encloses at least part of a voltage multiplier without enclosing a control circuit to minimize or eliminate electromagnetic interference in the control circuitry caused by the voltage multiplier. An x-ray source can include a negative voltage multiplier, a positive voltage multiplier, and a ground plane between the negative voltage multiplier and the positive voltage multiplier. The ground plane can minimize or eliminate electromagnetic interference between the negative voltage multiplier and the positive voltage multiplier. An air-filled channel, associated with the ground plane, can reduce weight of the x-ray source.