One of the things about digital circuits is that the chips usually require 5 volts to run, this is a problem when you have batteries in multiple of 1.5 volts.
The solution here to to either buy a PSU OR construct a simple circuit that provides the required power output.
The 7805 voltage regulator is ideal for this purpose. I have prototyped a 5v circuit for soldering up once all the other parts have arrived, mainly the dc jack sockets.
So I am using just 1 component for this. When soldered up I will use the dc jack socket and the male AND female headers so there are more options to connect / power other circuits. The prototype works really well. I will be using the 1/4 size adafruit protoboard for this when the other parts arrive.
1/2 size proto board with dc jack soldered up.