I am planning on recording a live concert in 32 bit float 192khz sampling rate stereo using an android phone What app should I use? How do I prevent the audio from clipping? Thanks.
You need to invest in an external mic for your phone or, better yet, ditch the Android idea and get a small hardware recorder. Here's why:
- As far as I know, there's no way to set manual record levels on an Android device using the built-in mic(s). This means your levels will be floating and changing constantly as the SPL (sound pressure level) changes at your listening position.
- The mics in even the best Android phones can't handle high volumes, and will likely clip at even a moderately loud concert (especially at lower frequencies). This is not a result of being unable to lower the record level. It's the mic itself that's distorting, and there's no practical solution to fix the clipped waveform.
- The linearity and overall frequency response of built-in mics isn't great.
A $100 portable audio recorder (like the Zoom H1N) will give you better quality than your built-in mics, plus true manual record levels. I also think you'd find the hardware recorder to be much more useful and versatile than an external mic system for your phone.
Finally, don't get hung up on the high sample rate and 32-bit resolution. Neither phone nor portable recorder will capture frequencies to justify a 192 kHz sampling rate (which translates to a frequency response out to 96 kHz). Typical microphones, and adult ears, fall about 80 kHz shy of that number.
Regarding bit depth: the dynamic range of 16-bit recording is quite good (96 dB) and 24-bit recording is really good (144 dB). Bit depths higher than that are beneficial for internal DSP processing, but represent complete overkill for the initial recording. No analog mic system delivers anywhere near that dynamic range. Maybe half that, on a good day.
Not to spark a holy war, but recording at 192/32 on a cheap recorder is like using a 5-gallon bucket to haul 16 oz. of soda. Record 24 bits at 48 kHz, and defy anyone to hear the difference.