If you had been missing Voodoo sound on Galaxy Note and S2, @supercurio has a nice surprise for you with release of Voodoo LOUDER for the devices. For the unknown, Voodoo Sound improves the quality of music and exploits sound chips extra abilities to get very high output volumes on the devices so you dont need those speakers.
Voodoo Louder gives a boost of +6dB on Galaxy S2 and 10.5dB on Galaxy Note. While analog amp switches are used in former, in Note it is using a combination of digital and analog amplification.
However the developer says that this app doesn’t bring sound quality improvements like Voodoo Sound but is designed to do the best. However I am hearing some users saying a 6DB on S2 is too high and its getting distorted. Download from here and its free.
Voodoo for Nexus S / Asus / LG and others :
For Others who are using NexuS S, Asus, LG extra there is a Voodoo App already available in both free and paid version. Free version requires to have a rooted devices but you will have to patch it on your own, failrly easy job but for one who do not want to take a risk, there is a paid version available which only needs a rooted device and superuser app for permissions. The paid version also supports Ice cream Sandwich update on Nexus S.