Love DSP Manager from CyanogenMod ROM? You can enjoy DSP Manager on stock Samsung Galaxy S III firmware now (CWM is needed though). DSP Manager is an equalizer that enhances sound processing capabilities. Let you modify headset, phone speaker and Bluetooth headset sound quality. Adjust dynamic range compression, bass boast, equalizer and virtual room effect. This mod is made for HTC One X actually but works on Samsung Galaxy S3 too. Want to try it?
Installation guide ~ How to install update zip with ClockworkMod Recovery on Samsung Galaxy S3? (Video)
Download DSP Manager for Samsung Galaxy S3 here.