Here's a short version:
Most (not all!!) pedals require 9vdc center negative power. Center negative looks like this:
Very likely what you need is a power supply that has this symbol and the words 9vdc on it. If you find one of those, you can daisy chain it with a daisy chain cable to as many 9vdc center negative pedals as you want.
Each pedal draws a certain amount of current. Most draw around 20mA (some draw a little less, some draw a LOT more). Many power supplies provide 200mA of current. If all of your pedals amp draw (amp draw means the amount of current taken) totals more than the power supply is capable of, then some of the pedals will not work and you will need to get a power supply with a higher current rating or an additional power supply.
Not all pedals run off 9vdc center negative. Some 9Vdc pedals don't daisy chain with others. Electro Harmonix is famous for screwing with voltages you need for their pedals. You should let us know what pedals you're dealing with if you're not sure about the voltage requirement.
If all of your pedals are 9vdc center negative a Visual Sound one spot should do you well. They provide 1700 mA which is plenty to start.
). Very reliable and always had great service from them.
