Make sure you are using a recent version of Google Chrome.
Also before you enable microphone input either plug in headphones or turn the volume down if you want to avoid ear splitting feedback!
Online Voice recorder is a free voice and audio recording webapp. Record your voice and play it when you are done. Just click record and pause when you are done. Choose which file format you want to download ( currently there are 2 file format's available mp3 and wav ).
Or you can even play the files before downloading them to ensure quality. This is the most simplest yet best and most powerful chrome app which will help you to record mpe, audio or your own voice. Just one click and it is done.