sox source.wav -r 48000 source.wav -- 48khz conversion with sox
To change all the directories to 755 (drwxr-xr-x): find /opt/lampp/htdocs -type d -exec chmod 755 {} \;
To change all the files to 644 (-rw-r--r--): find /opt/lampp/htdocs -type f -exec chmod 644 {} \;