High Definition Audio

[grahambaster]

Is there a consensus as to what HD audio in regards to streaming is? Personally, I would think of 320kbps mp3 audio or a comparable format as high definition.

 

Any thoughts?

[GKIye]

One of the BW members (BrutishSailor) aka Rob is very familiar with FLAC

He has also the knowledge how to use it with streaming software

Hope these details where helpful

[jessewillem]

Lossless formats like FLAC and Wave are really the ones that you should use when you want "HD" quality audio. MP3 and other lossy formats use psycho accoustic models to remove information we can't hear. That isn't a problem when you have 1st generation lossy file from a lossless file. But if you begin to stream that file again with a lossy format, the quality will be worse. (Even with 320 kbps MP3)

 

Using lossless files from good quality sources will also give you the better quality when you stream with a lossy format (MP3, Ogg Vorbis, Opus and so on), because it will be a 1st generation lossy file/stream, instead of a transcoded lossy file from a lossy source.

 

Not many radio automation programs support FLAC, but most will do wave files. But take in mind that wave's are bigger than FLAC files and other lossless compression formats for audio. And they don't support tags. But converting FLAC to Wave is possible without quality loss.

 

Streaming with lossless formats is still a bit unpractical to my idea. As the file is always VBR, the player buffer can't really have a steady buffer as with a CBR lossy format. So buffering can be a problem. That also gives problems with low speed internet connections.

 

And also: streaming lossless formats will really use bandwidth.

[Vanlen]

MP3 by definition is very, very brittle which has proven to cause fatigue in listening and add to that even worse if you export the final sound with compression and that takes out even more hi fidelity. People under 25 are starting to go...hmmmm, and turning to LP's with turntables for a sound they can't describe. That my friends was hi fidelity. Remember the sound of vinyl and original cd's that' didn't compress the hell out of the music. There is nothing better. Sure, MP3 was good for it's day back in the 90s but now with faster computers and increased bandwidth getting the 44.1 16 bit experience is getting closer to reality in a stream. Opus and ACC+ are a good mid step.

 

Interesting times as we move forward.

[voodoohippie]

I've noticed that AAC+ even in 64K does not sound as pitchey as does the Mp3. Slowly more and more smartphones are able to handle AAC+ but its interesting to note that the Roku does not (I don't know about the V2 of Roku). When more smartphones can handle AAC+ I think you'll find more folks streaming in AAC+ as well as encoding their music in 64K AAC+ or even 96K AAC+. I mean 64K AAC+ sounds every bit as good as 128K Mp3 if not a little better.

[GKIye]

Thats right ...

Both Roku, Receiva and Nokia Internet radio who provides, as platform, streams to their mobile users, or to people who have a portable radio who can receive internetradio ... They all accept the as basic known format IP + Port as mp3 stream

The bitrate is up to the streamer ... 128kbps ain't a problem if used by Asian mobile phone users

To general projects ... 64 untill 94kbps gives very good stable results

[voodoohippie]

Remember if you stream @ 64K the sample rate needs to be dropped to 22.1 Khz. You won't believe how many broadcasters forget to drop it from 44.1Khz to 22.1Khz. And possibly streams @96K need to drop the sample rate to 22.1 as well otherwise you hear that SSH sound when even an S word is spoken and certain instruments cause a hiss as well in rates less than 128K unless the sample rate is also dropped.

[jessewillem]

Remember if you stream @ 64K the sample rate needs to be dropped to 22.1 Khz. You won't believe how many broadcasters forget to drop it from 44.1Khz to 22.1Khz. And possibly streams @96K need to drop the sample rate to 22.1 as well otherwise you hear that SSH sound when even an S word is spoken and certain instruments cause a hiss as well in rates less than 128K unless the sample rate is also dropped.

44.1 KHz as sample rate will be fine if you use HE-AAC/AAC+. If you're using MP3 at those bitrates than you will hear those sort of artifacts. That's why we have HE-AAC today

 

The SSH sound on a S is called a sibilant. Which you can filter out with good multiband sound processing.

[voodoohippie]

Yes that was what I was referring to was Mp3 since I was talking about Roku, Squeezebox and many devices that for some reason don't support AAC+. I have streamed with AAC+ @ 64K 44.1Khz and it sounded awesome. but I noticed that some Smartphones just could not tune in AAC+. Plus the TuneIn app has some problems with AAC+. It really is a pity that some devices are still in the 90 technology.

 

I do predict however that after about a yr or two you'll see more support for AAC+. Until then I won't scrap the Mp3 @ 128K.