Major improvements to audio at Zencoder, and why this matters

General nitpick for articles like this: if you improved X about your service by switching from application A to application B, simply say it. Phrasing like that used in this article implies (falsely) that Zencoder wrote their own encoder.<p>"We made our web server 5 times faster!" might sound amazing, but if you really mean "we switched from Apache to Nginx", it's misleading.<p>Also, FAAC is widely known to be pretty bad. Even LAME MP3 is quite a bit better at 128kbps, to say nothing of Vorbis, good AAC encoders like Nero or Apple, and Opus/CELT.

I thought it was a well-known fact that FAAC produced very bad output. Or at least well known by anyone who might be working for a company for whom AV compression is all they do.

So after all that, what encoder are you using?

Which aac encoder does iTunes use? Is it considered pretty good?

I found the ringing in the new 16kHz sample to be a bit bothersome. It sounds like theres a tonal peak in the frequency response near the upper end of the frequency range. The peak would be less bothersome if it were spread out more.<p>Edit: is the new resampling done by something like Shibatch SSRC or libsamplerate's SRC?

This is awesome Jon! What audio processing tricks did you use?

Can I just have lossless audio, please?