Stereo vs. Joint Stereo

[Lite]

Did you know that the "Joint Stereo" mode has a much greater efficiency and better transmit frequency than simple "Stereo"?
Joint (audio engineering) - Wikipedia, the free encyclopedia

[Dan]

nice one, i actually read that wiki page a while back, makes sense, however if a ear can notice a difference? kinda hard to tell in my opinion.

[Lite]

The AH.FM MP3 Streams is in a simple "Stereo", not in "Joint Stereo". That's why I'm saying it!

[Tarek]

I think he means if it does not make a noticeable sound difference you can save streaming/set storage money.

[t4e]

joint stereo produces smaller files and is useful at bitrates lower than 160 at which usually provides a gain of perceived quality

[Lite]

Joint Stereo does not create smaller files. Difference is only in quality of sound! Teach theory! It only significantly increases the efficiency by more than a clever arrangement of data. In fact, it reduces data redundancy, which allows you to use freed space for nonredundant data. Joint Stereo should be used even at 320 kbps. It makes winning even with this bitrate! If you do not understand why, I recall that the original bitrate CDDA - 1411kbps!

And the difference in the sound very much! She felt even at 320kbps. In simple Stereo sound is empty. In order to verify this is enough to compare the same track in Joint Stereo and Simple Stereo on normal (or high quality) equipment.

[t4e]

makes no difference to the quality except at low bitrates, as i said, its the same argument between 192 and 256/320 streams....there is no perceivable difference in the sound quality, just a waste of bandwidth with 256 and 320...


so if Joint Stereo its so much better quality why don't record companies use it on commercially released cd's?

[Lite]

Because CD-DA format is not compressed. Data is written in it by reference in the form in which there is, just as they look so peted as Digital-to-analog converter. converts the analog sound.
Speaking of online studios and companies, not all their staff so qualified (or they simply give a damn). If you follow the trance releases in MP3 format to the online shop, you should have noticed a sharp transition with Lame 3.93 (even 3.90) on Lame 3.97 somewhere in the beginning of 2007 or in 2008 (now do not remember exactly). It is only because I wrote and sent out to all of them (so that he knew about) with a request to (council) is used to update the MP3 codec and use Joint Stereo. Only in this way they did. They themselves had never thought before, or just not care again. But the quality of a Lame with each release increases significantly! And you say the company...
We already have Lame 3.98.2, but they do not want to upgrade. Even though I again sent them a letters...

[t4e]

let me get this straight here, i read about 10 times and i'm not sure what to make of your statement there, are you implying that YOU, personally, are the reason the labels use joint stereo?

[Lite]

No. I did not say about the labels. I talked about these stores:
audiojelly.com
beatport.com
djdownload.com (еhis seems no reaction at all)
dance-tunes.com
trackitdown.net
I did not say that thanks to me they use Joint Stereo. As before, some of them use Joint Stereo, others - Simple Stereo. But thanks to me almost all of them went at least Lame 3.97.

If I'm still not convinced you about Joint Stereo, then talk about it more simple. Simply put Joint Stereo calculates all that is the same in each channel and writes it in one stream, but all that different in another. Thus information that is the same in both channels (in other words mono component) is not duplicated in each of them as in the case of Simple Stereo. Regarding RIFF Wave (CD-DA) once again say that there is Joint Stereo is simply not necessary, and can not be realized because information is stored in its original form. The only actions that are performed on it when performing digitization is discretization and quantization.

[Tarek]

I understand how this may save space...thinking of Joint Stereo as de-fragmented Stereo..but I dont understand how this makes for better sound. After all, defragging your hard drive or registry will certainly improve performance, but it will not add power to the processor or add more RAM or HDD space..

[XDR]

Originally Posted by Lite

If you follow the trance releases in MP3 format to the online shop, you should have noticed a sharp transition with Lame 3.93 (even 3.90) on Lame 3.97 somewhere in the beginning of 2007 or in 2008 (now do not remember exactly). It is only because I wrote and sent out to all of them (so that he knew about) with a request to (council) is used to update the MP3 codec and use Joint Stereo. Only in this way they did.

Do not even for a second think that you were the only person telling them about this.

Originally Posted by Tarek

I understand how this may save space...thinking of Joint Stereo as de-fragmented Stereo..but I dont understand how this makes for better sound. After all, defragging your hard drive or registry will certainly improve performance, but it will not add power to the processor or add more RAM or HDD space..

What it would do is create more space for relevant information in a similar-sized file.
An mp3 of the same size would sound better in Joint-Stereo than in Stereo because it contains more relevant data on the music.
I'm not sure if this is exactly how it works but this seems to me what he is implying.

[t4e]

Joint stereo is a technique used in audio coding to improve the efficiency of the coding of the left and right channel of a stereophonic audio signal. Joint stereo coding takes advantage of the fact that both channels of a stereophonic audio signal contain to a certain extent the same information.


this is a pretty good and simple explanation

Basically the idea is that for the most part, left and right channels are very very similar. So why bother having twice the data for most of the song when lots of it can be duplicated for each channel? This is where the Joint Stereo idea comes in. It compares the left and right channels and works out how much data it can save by making them identical and encoding the data once. This means there will be elements of your wav that are, in effect, mono. These are only elements however and it is a very useful addition for the reduction of file sizes.

There is a secondary pass to the Joint Stereo formation, which is quite clever and uses another psychoacoustic model. The theory is that we are very bad at telling where very high and very low frequency sounds are coming from. A practical example of this is subwoofer speakers - they can be stuck in the corner of the room away from the other speakers and you still can't really tell that the bass is coming from there. Taking this idea into consideration, bass sounds and very high pitched sounds are made mono - because you can't tell the difference.

Of course, with this method you do get a reduction in the stereo separation in your audio. Many people cannot tell the difference but it is there so if you want the best quality you may want to go for the normal stereo mode. Also, it can introduce errors that can't really be regained by increasing the bitrate. If the audio sounds a little crappy, try normal stereo.

[Lite]

Yes. Seems you now understand what the Joint Stereo. I would only add that the gain in the preservation of frequencies using Joint Stereo is far more important than a little more detail on individual stereo frequencies. Sound even at 320kbps mode Simple Stereo is empty (lost frequency) and clip-clopping. It can be heard by comparing the derivatives of each of the methods with the original matherial. It is better to use the latest version of Lame with maximum quality settings. Only so the difference will be clear. And these distortion arise on the low-quality encoder, and not on Lame.
Incidentally in AAC format but a heap of different innovative techniques used and the Joint Stereo. I hope you have heard how good AAC even at low bitrates.

And when using lower bitrate than 320kbps Joint Stereo effect is simply undeniable! At 128kbps bitrate and lower (even at 160, 192) Simple Stereo is different from Joint Stereo as heaven and earth.

I specifically re-checked this now. Used Lame 3.98.2 with the settings:
Joint Stereo:-b 320 -m j -q 0 --noreplaygain
Simple Stereo:-b 320 -m s -q 0 --noreplaygain
Joint Stereo retains much more frequency, the sound is softer and seems like more pleasant to the ear, and Simple Stereo Stereo stores a little more detail, but the sound of depleted frequencies and is well audible when compared with the original. Simply put, none of these methods at a low bitrate is not able to repeat the quality of the CD-DA, but Joint Stereo closer at him by the frequency component (which is pleasant to the ear), and Simple Stereo closer in stereo detail, but the frequencies are depleted.
And the difference with the original more audible in Simple Stereo.
To listen used Foobar2000 0.9.4.5 with SSRC Resampler Plugin (48000Hz) on Normal Quality in conjunction with Aureal Vortex 2 (AU8830A2).
Resampler is needed to remove distortions in the audio with AC'97 soundcards by means high-quality resample to the frequency of 48000Hz (internal operating frequency of AC'97 sound cards).

Although not exclude the possibility that someone will be more pleasant sound Simple Stereo at 320kbps. But at lower bitrates, Joint Stereo Advantage becomes more apparent.

By the way here you can hear the difference right now:
http://etn.luon.net:8100/
http://etn.luon.net:8200/

Share where you got such an explanation, please.

[t4e]

i understood JS before too, i still don't agree with some of your views, but there is no point in arguing since we're each set on our beliefs


AAC is the best....128AAC sounds the same as 192 MP3, at considerable less bandwidth

unfortunately many people are uneducated about the whole thing and don't even bother to try it, one major point of ignorance is thinking that AAC is the same as aacPlus , than you have the online radios that are not willing to make the necessary changes to accommodate AAC