The term 'phantom' was coined because no additional wiring is needed to carry the power from the power source to the microphone — it is 'magically' passed along the microphone cable using the same wires that carry the audio signal.

Phantom powering is only possible with balanced wiring systems (the cables have two cores and one outer screen) and most studio mixing consoles have their own internal phantom power supplies that feed their microphone inputs. Depending on the mixer, the phantom power may be globally switched or switched per channel. Separate phantom power supplies are available (some running from multiple batteries for mobile use), and all serious microphone preamplifiers also have integral phantom powering.

• CAPACITOR microphones require a power supply to polarise the capsule and to drive the preamplifier which is normally located inside the microphone body close to the capsule. Back-electret mics and active DI boxes need power to run their onboard preamps. To avoid the need for a separate power supply, the majority of capacitor microphones (other than tube mics, almost all of which need a separate power supply anyway) and most studio-quality back-electret models use the universally standard 48V phantom powering system, though some models will operate at lower phantom power voltages at the expense of some loss of headroom.
• DYNAMIC microphones do not require phantom power. However, where the phantom power on a mixer can only be switched globally, it is safe to connect balanced dynamic mics provided that balanced cables are used. This is because the same phantom voltage is present on both the hot and cold pins of the mic cable and so no current flows. Take care, as any dynamic mics not wired for balanced operation could be damaged if phantom power is applied.