Encoder has a massive impact on results: <a href="http:&#x2F;&#x2F;www.compression.ru&#x2F;video&#x2F;codec_comparison&#x2F;h264_2012&#x2F;mpeg4_avc_h264_video_codecs_comparison.pdf" rel="nofollow">http:&#x2F;&#x2F;www.compression.ru&#x2F;video&#x2F;codec_comparison&#x2F;h264_2012&#x2F;m...</a><p>This actually goes for most codecs, including both audio and video (have a look at the AAC encoders at <a href="http:&#x2F;&#x2F;soundexpert.org&#x2F;encoders-128-kbps" rel="nofollow">http:&#x2F;&#x2F;soundexpert.org&#x2F;encoders-128-kbps</a> )