TL;DR: Seeking advice with building a visual audio feedback detection app for mobile devices.
Hi, my name is Bohumir and I'm a programmer and amateur musician. As a hobby project I'm building an application that detects and visualizes musical tones in real-time. I've realized that another app based on similar principles might be useful to sound engineers. So for curiosity I've started writing a mobile/tablet application that would detect when audio feedback occurs on the live stage and what's the feedback frequency(ies). This in turn might help the sound engineer (SE) manually turn down the corresponding band(s) on the EQ. And I'm wondering if anyone else is interested in this problem. I'm asking myself the following questions regarding the fight with feedback and I'd like to ask you for advice.
1. Does the frequency need to be detected exactly or just seletecting its corresponding EQ band is sufficient and more interesting?
2. Is for less experienced SEs detecting the corrent band by ear hard (neither fast, not precise) and more more experienced ones a lot easier?
3. Does even for experienced SEs detection by ear get worse if they're tired after many hours of work and/or would they like to confirm his guess by an exact measurement?
4. There exist some general purpose real-time spectrum analyzer hardware units and mobile app. Do you thing a specialized app that would directly tell you the corresponding band on your EQ (in addition to the precise frequency) would be more beneficial?
5. Also there exist some expensive hardware feedback eliminators that automatically adjust the EQ on your behalf. Many people tell that they are too aggressive in killing feedback at the expense of making the sound too dull. Do you thing a more lightweigtht and not fully automated thing like a mobile app could serve better?
6. Do you thing that maintaining the list of feedback frequencies that occured during the live performance (eg. after the initial setup) would be useful? Eg. to quickly eliminate any of those if it occurs again.
7. Is it important that the feedback detection distinguish feedback squaks from ordinary instrument and voice tones so that the music tones are not regarded as feedback?
8. Is the almost real-time responsiveness (eg. delay of just several milliseconds) really important?
9. Do you think that it is critical that the app just gets along with the built-in microphone or connecting to an auxiliary audio outout from the mixing console is not a problem?
10. Would a phone or a tablet with bigger screen be better suitable for such an app? Or it doesn't matter?
I'd be very grateful if you could look answer or just discuss any one of those questions. Besides you raise your karma I could provide you with the application since the early development and fine tune the hand-crafted app to your specific needs. Overall feedback detection seems to be quite an interesting problem to solve and I'd be glad to hear if such an app helps saving somebody's time or maybe even a live performance
Thanks a lot!