Hey! I'm new to the whole Saber building hobby, so I really need some help to ensure that I have the right parts for my big electronic makeover. My saber I bought second hand it the only electronics it came with were a relatively nice LED that I'm happy with and won't change yet, and a double AAA battery pack. However, Episode 8 is right around the corner and I need sound! Therefore, I have decided to follow the Basic Saber with Sound 2 build style (https://www.youtube.com/watch?v=BrA-...ature=youtu.be) as it looks like a good system to build on, relatively easy to assemble, and also good for my specific saber because it is one solid piece. The video had links to the shop for what was required with the build, but I ended up confused with the differences between a 28mm Bass speaker and a 28mm Premium speaker, the difference between the Panasonic Li-Ion 18650 3.7V 3400mAh PCB Protected Rechargeable Battery (http://www.thecustomsabershop.com/Pa...ItemId=6975169) and the Li-Ion-18650-37V-2600mAh-PCB-Protected-Rechargeable-Battery-Module (http://www.thecustomsabershop.com/Li...ItemId=6975167). Is there really any difference between the two and will I need to get different resistors or anything depending on which one I buy? Also, I am a little cramped for space in my hilt so is one of the batteries noticeably shorter? Thanks!!

Note: This will be the first real electrical project I'll have ever done, so sorry if some of the questions are really dumb :P