I suspect this kind of sonar application is why TI is making analog-to-digital conversion chips with 31 bits of resolution: http://www.ti.com/lit/ds/symlink/ads

I suspect this kind of sonar application is why TI is making analog-to-digital conversion chips with 31 bits of resolution: http://www.ti.com/lit/ds/symlink/ads1282-ht.pdf http://www.ti.com/lit/ds/symlink/ads1282-ht.pdf Compare to 16- to 24- bit resolution in your typical audio processing chain.