I am deaf and looking for a way to enhance my hearing of the sounds made during the coffee-bean roasting process, while using another app (Roastmaster). Essentially I need to hear sounds similar to popcorn popping. Turns out the frequency is somewhere about 12MHz. I have the i-Microphone that I can use if that would help. A problem with it is that it prevents using earphones, as it uses the audio jack. Is there an app that will let me listen to amplified and, preferably frequency-filtered sounds in real time, using an iPad2? uListen works when I hold the iPad mike close to the source of the sounds but it is a little 'primitive.' Anyone have any thoughts about this? An audio frequency filterer and analyzer, with sounds and recording in realtime, that could be used at the same time as another app is deployed. That would be the ideal.