Planning on building my first crossover. I've read about everything I can find on the web, but don't quite understand the concept of by-pass capacitors. Am I to understand this is a small value, high quality cap that is wired parallel to the main capacitor? Is this necessary? Plan on using PE parts, as well as one of their PC boards, part number 260-120. Will be using this to crossover between mid and tweeter in a bi-amp set-up. Also, there is a big difference in price between their Solen, Audiocap, and KimberKap capacitors. Is it worth the extra expense to go with the best? All comments will be greatly appreciated.