I've been trying to boost the maximum volume obtainable through the audio jack of my phone (Nexus 5). Instead of installing equaliser or volume boosting apps, I thought I'd go about this the technical way:
XDA forums suggest a "MOD" that involves modifying your
mixer_paths.xml file located at
/system/etc/ (root access naturally required) to increase your speaker or headphone volume beyond the set limits:
Find: <path name="speaker"> You will see this string just below it: "RX7 Digital Volume" value="88" The value is the only part we are going to adjust. For the mod above, I changed the value to "93". The default value is "88" and I would suggest not to go over "95". To change the Headphone volume: Find: <path name="headphones"> Look for these strings below it: "HPHL Volume" value="15" "HPHR Volume" value="15" Again all we are changing is the values (ensure both are set at the same number). For the mod above, I changed the values to "20". The default values are "15" and I would suggest not to go over "20".
How does this work? Does Android artificially limit the maximum volume and this "MOD" bypasses those limits? Or does it compromise audio quality?