[http://en.wikipedia.org/wiki/High-Efficiency_Advanced_Audio_Coding HE-AAC audio] v2 (with SBR + PS) is the superb audio encoder used to encode high quality audio at really low bitrates (32 kbit/s). Quote from Wikipedia "''Data from this testing also indicated that some individuals confused 48 kbit/s encoded material with an uncompressed original.''"

In order to quickly compile your [http://217.20.164.161/~tipok/ libaacplus] library, you can type the following commands in your shell:
{{{
# apt-get install libfftw3-dev pkg-config autoconf automake libtool unzip
$ wget http://217.20.164.161/~tipok/aacplus/libaacplus-2.0.2.tar.gz
$ tar -xzf libaacplus-2.0.2.tar.gz
$ cd libaacplus-2.0.2
$ ./autogen.sh --enable-shared --enable-static
$ make
# make install
# ldconfig
}}}

P.S. If you are using Ubuntu, you'll most probably have to use `sudo` for the last 2 commands, like:
{{{
$ sudo make install
$ sudo ldconfig
}}}

In case that website above (hosting libaacplus) goes offline, you can download the copy of that tar.gz file from here:
(MD5: 3fc15d5aa91d0e8b8f94acb6555103da)
{{{
$ wget http://ffmpeg.gusari.org/uploads/libaacplus-2.0.2.tar.gz
}}}

More info at: http://tipok.org.ua/node/17

'''NOTE: libaacplus is a non-free library, so you won't be able to build GPL alike FFmpeg with this library, i.e. your FFmpeg will not be redistributable.'''