On Tue, Sep 06, 2005 at 09:56:06PM -0500, Jay Krivanek wrote:> Yea, don't get me wrong, ogg is definitely an awesome format but aacplus v2 > is currently the leader in high fidelity quality at low bitrates. 24kbps > aacplus even kicks ass in my view.Is that 24kbps AACPLUS a full 44.1kHz stereo signal with frequencies preserved up to at least 15kHz? (Just curious, not criticising.) As a datapoint, Vorbis aotuv b4 gives acceptable quality with q=-1.001 44.1kHz stereo at approximately 44kbps. -- Paul Martin <pm@zetnet.net> (work) <pm@nowster.zetnet.co.uk> (home)
Yes it is 44.1kHz. However SBR is not the original, everything higher then 22.05kHz is recreated. Also Parametric Stereo recreates the Stereo experience. The actual audio data is simply a 24kbps AAC stream at 22050 mono. Also it is by no means perfect. The highs do have an artificial feel to them and a little echo. For what it is though most people don't really get annoyed by it and are quite pleased with the feel of it. -----Original Message----- From: icecast-bounces@xiph.org [mailto:icecast-bounces@xiph.org] On Behalf Of Paul Martin Sent: Wednesday, September 07, 2005 6:43 AM To: icecast@xiph.org Subject: Re: [Icecast] AACPlus Shoutcast v1.90 On Tue, Sep 06, 2005 at 09:56:06PM -0500, Jay Krivanek wrote:> Yea, don't get me wrong, ogg is definitely an awesome format but aacplusv2> is currently the leader in high fidelity quality at low bitrates. 24kbps > aacplus even kicks ass in my view.Is that 24kbps AACPLUS a full 44.1kHz stereo signal with frequencies preserved up to at least 15kHz? (Just curious, not criticising.) As a datapoint, Vorbis aotuv b4 gives acceptable quality with q=-1.001 44.1kHz stereo at approximately 44kbps. -- Paul Martin <pm@zetnet.net> (work) <pm@nowster.zetnet.co.uk> (home) _______________________________________________ Icecast mailing list Icecast@xiph.org http://lists.xiph.org/mailman/listinfo/icecast
On Wed, Sep 07, 2005 at 06:51:21AM -0500, Jay Krivanek wrote:> Yes it is 44.1kHz. However SBR is not the original, everything higher then > 22.05kHz is recreated.Are you sure you mean those figures? Wouldn't there be a lot of aliasing? http://en.wikipedia.org/wiki/Nyquist_frequency> Also Parametric Stereo recreates the Stereo experience.Similar to what Vorbis does, then?> The actual audio data is simply a 24kbps AAC stream at 22050 > mono. Also it is by no means perfect. The highs do have an artificial feel > to them and a little echo. For what it is though most people don't really > get annoyed by it and are quite pleased with the feel of it.Right... so anything above 11kHz is simulated by generating harmonics? -- Paul Martin <pm@zetnet.net> (work) <pm@nowster.zetnet.co.uk> (home)