what is power supply ?

what is power supply ? This article is about the common off-line switching power supplies used Preamplifiers

what is power supply ? Power Supply for Preamplifiers

what is power supply ? Power Supply for Preamplifiers

what is power supply ? +15 and -15 , GND

what is power supply ? One unit of Preamplifiers has begun working, while the second one will be operational

The power supply

+15 and -15 , GND

provides the components  with electrical power.