Creating promo drops can be fun and easy particularly if you are a Mac user. Garage band is a powerful little program that comes with all new and most used Macs and has tools to give you the ability to create drops for your mixes with a lot of effects built right in the program. If you are strictly using a PC you can edit and create drops using any multi-track editing software. Audacity is free and amazingly simple, robust and stable for a free program. it doesn't have the effects that Garage Band has however with some time spent searching the net sound elements can be found. One of the added values of being a subscriber to TM Studios Prime cuts is access to a large library of effects that work great for drops. And Prime cuts is and excellent music service to keep your library up to date and legit. I've used them for years.