Using USB to send sound signals
...but now i want to make it reactive to sound. There is a catch though. I want it to receive the sound signal over USB and not by using a microphone wired up to the arduino.
Do the sound processing on the part of your kit that can handle it (i.e. your PC), send the results over the USB to the Arduino, and have it control the LEDs based on those commands.
What will you use for software on the PC?
Without going into all of the "difficulties", I'll just say, that's probably impossible with that the same time Arduino. Plus, the computer would have to send digital audio to the Arduino plus a soundcard and without special software or drivers the computer can only use one "soundcard" at a time...It's fairly common to send a line-level (or headphone level) signal to the Arduino, and you can easily "split" the signal, sending it to your amp and the Arduino at the same time.Just to get you started take a look at my World's Simplest Lighting Effect. ...It's a pretty boring "flicker" effect so it's mostly just an example but there is a schematic showing how to bias the input so it can read the negative-half of the AC audio signal.USB can be useful if you have a "programmed show" with the same-exact music and same-exact lighting every night. But if you want it to "react", an analog audio signal is the way to go.
No experience with any PC based sound processing software.First you have to figure out how you want your lights to react. What exactly should they react to? Volume, rhythm, pitch come to mind. Maybe others. You have to come up with very specific ideas as "reacting to music" is way too vague to even start turning it into something computers can work with.Second step is to find software that can recognise this, and turn it into a specific command for your LEDs.Now the easy part. Send that command to the USB port in plain text data, have the Arduino read it (there's a "serial communication basics" thread out here telling you exactly how that works), and control your LEDs accordingly.
I'm not sure what software to use as i'm brand new in the field. Do you have any experience with any software that can help me with my project?
Nothing that makes COM outputs synchronized to sound. PJRC has a sound suite to run on their ARM Teensies with audio DACs, it will likely run on a Due, you might do everything on one board with that.If you can get the sound out of the PC into MIDI, Arduino can read those signals but I've not worked enough with MIDI to say how to get it to read sounds. MIDI is supposed to able to drive lots of leds according to one Arduino article I have read.Since you're going to have to learn a lot to do anything, you might as well check out options. Is it possible that the effects you want could be made as circuits driven by sound signal?