Its not your bad, I am explaining it poorly, plus for me its hard to conceptualize entirely since I am trying to just understand the process of how to make them interact first.
The plotter would be made using the arduino with 2 stepper motors using the EasyDriver board (EasyDriver - Stepper Motor Driver - ROB-12779 - SparkFun Electronics). So the steppers would be attached to the arduino using the easy driver board.
Yes, you are correct. I am using a microphone breakout sparkfun (SparkFun Electret Microphone Breakout - BOB-12758 - SparkFun Electronics) and the .pde I originally used to acquire the data, which is amplitude, is from the Arduino Cookbook. I was thinking about doing DSP related processes using the Arduino but I haven't looked into it that much and I wanted to used Max/MSP to do that. That being said, thats why I am using the streaming data from the electret microphone. At this point I am just gathering the data within Max/MSP but now I want to send it back to the Arduino so it will plot a point based on the amplitude data.
It all boils down to taking the acquired data from the microphone (amplitude) that is hooked up to the Arduino, this data is read by Max/MSP, and then is sent back to the Arduino where it will plot a point. Does it make sense? Would this work using MaxMSP to send the data back out to to a plotter? I know you can do it with servos but I haven't explore it too much but I should do that tonight since I will have some time.
Sorry if I am persistently confusing. I really really realllllyyy appreciate the help and thank you a ton for the response!