Depends. If you dithered it really badly, and several times you will start to notice it on a good sound system, with the volume up really loud. You notice dither noise more when compared against sounds which are really low level. i.e. where elements of a track fade out to silence.

If its well dithered and dithered only once, then its really really hard to pick up on but I guess thats the point. I couldn't tell a well dithered mix from the same mix without dither because I'm just not that accustomed to all the noise shaping algorythms and how they sound. Plus I am not monitoring on a super senstive sound system at really high level.

It might also be hard to notice if you don't know what dither noise sounds like so you might want to try dithering a sine wave test tone, use a notch filter to eliminate the sine wave after you render it with dither on. Then increase the volume something chronic. Its really obvious then. So you can imagine what would happen if you kept on dithering it. It would just add more cumulative noise to a mix.

When you compare a non dithered sine wave to a dithered sine wave after you have truncated bitrate, and you play it really loud on a really good sound system, identifying which one is the dithered sine wave and which one is undithered is really easy. Because quantisation noise sounds so different from dither noise. Quantisation noise is really really annoying on your ears at high level.

Theres no real point uploading a dithered mp3 as the last thing you would notice underneath the compression is dither noise - plus you probably won't be doing the comparison at over 100dB since quantisation noise manifests at around -100 to -140dB anyway. Plus the quality of the encoder will make it more or less difficult to indentify.

It wouldn't be such a big deal but its one of those things which isn't hard to fix. Its stupidly easy - just turn dither off.

Its not like its massively difficult to avoid this problem. It takes 1 click so I would recommend saving yourself the trouble later on and just get it right from the get go.

In the end, I think regardless of the technicalities, learning about dither and not dithering when you don't have to shows that you care about your tracks. That you really want to make them the best they can possibly be - even if you have to work alot harder to make a 0.01% improvement on your songs. I think that kind of effort pays off and it shows in the finished product. Its a good work ethic if nothing else.

I genuininely don't think anyone got anywhere in this industry or in life by going 'fuck it - it doesn't matter.'

Last edited by Derivative on Mar-09-2007 at 13:34

There's various reasons why well done one-pass dithering with it's relative level of -94dB is inaudible.

First your normal listening environment will have a really hard time to reproduce the necessary dynamics of more then 94dB.

Secondly it depends on the ay your DAC works. It may do some dithering on it's own so all you will hear is the DAC dither in both cases.

Another thing is that broadband loud signals will shadow softer (dither) noise. So if you dither the typical fat JP80xx strings, you will hardly hear a difference.

Not to mention that the digital audio format must be able to reproduce the full 94dB dynamics, MP3 is not.

With about 25dB headroom and in a really quite environment you could be able to hear the difference of dithering when digitally amplifying to full scale.

btw. adding noise with dithering is one thing. But dithering is not just simply adding noise to the LSB. In most cases dithering involves noise shaping which is some special filtering that can affect the high frequency range. So you might notice differences in sound that do not emerge from the introduced dithering noise.

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maybe someone said it already but you really aren't going to hear the side effects of dithering with "hot" music like EDM.