What is parallelling capacitors about?
Parallelling capacitors is using two or more capacitors instead of one. When these are placed in parallel with one another, their values are added together. For instance, if you use two 1000 ufd capacitors in parallel, the capacitance through both of them is 2000 ufd. But most often, capacitors are parallelled to enhance different parts of the frequency range. Some people doubt that this has any effect and some people even suggest reasons why this may be detrimental to sound quality! If you are building a Gainclone for the first time, I suggest not parallelling. You can always try it later if you want.