Comment 3 for bug 1494155

According to Alexander Patrakov's evaluation, both speex-float-5 and speex-float-10 are same or better than libsamplerate's highest quality.

So far we've trusted his word on that. If you want to challenge that, I suggest you do so on the pulseaudio-discuss mailinglist.

For reference, here's a link to the first part of his evaluation, including some graphs: http://comments.gmane.org/gmane.comp.audio.pulseaudio.general/21051