A Bio-Damping Feedback Transducer was a component the Doctor needed to dissipate the force of an impending explosion from an overloading Foldback Quasar Engine through the Wi-Fi. The Doctor used a volunteer from the audience at the Proms as the component. Although he dismissed any side-effects, the Doctor said those who had their mobile phones on would die and the volunteer might develop x-ray vision and turn into a giant bird. (Doctor Who at the Proms (2010))