# 32 bit float to 16 bit - to dither or not to dither?



## chrisphan (Dec 11, 2017)

I mastered all of my tracks with Ozone 7 at 32 bit float. Is it necessary to apply dither when I export them to 16, or 24 bit?
I found the answer is always yes when going from 24 to 16, but for some reason couldn't find anything about going from 32 bit. 
Thank you!


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## bjderganc (Dec 11, 2017)

According to Goodhertz there is always distortion when reducing bit depth: https://goodhertz.co/good-dither
I emailed them the other day about this and they said it will help (i.e. their dither will have less noise) when reducing from 32 bit if you apply effects, like you’re doing. I’d be curious to check out some real world examples though.


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## WhiteNoiz (Dec 12, 2017)

http://productionadvice.co.uk/when-in-doubt-dither/
http://productionadvice.co.uk/when-to-dither/
http://productionadvice.co.uk/dither-or-distort/

Oh, here from Izotope:


http://lmgtfy.com/?q=izotope+dither+manual


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## Living Fossil (Dec 12, 2017)

You can imagine a 32bit floating signal as a 24bit Signal (which contains the "information") with additional 8bits that permanently adapt the level of these 24 bits.
So yes, you should dither it.
(in Ozone, you have different options of the amount. I always use the most moderate ones)


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## chrisphan (Dec 12, 2017)

Thanks everyone! This also makes me wonder if I had exported my mixes, before mastering, from Cubase 32-bit to 16 or 24-bit, would Cubase have automatically dithered them? Or would it have skipped that step?


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## chrisphan (Dec 12, 2017)

I just found a thread in the Steinberg forum about this. A knowledgeable member, Jarno, apparently said that it's not always needed: https://www.steinberg.net/forums/viewtopic.php?p=188973


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## wst3 (Dec 13, 2017)

I'm going to be a little bit contrarian, sorry.

Dither solves a very specific problem when one is reducing the word length of an audio file. It adds noise to mask the existing noise that results from truncating, or even re-calculating, the value for a single sample. There are some wonderful papers written by folks much smarter than I on the web, if I find some of my favorites I'll post them later.

But that's it, there is no magic, it's just a very cool psycho-acoustic trick. A very effective trick most of the time, but still a trick, and it does depend, a lot, on the content you are processing.

My advice, which isn't completely contrarian, is to make dither the absolute last step - even after sample rate conversion if you are doing that too. Keep the file format at 24 bits or 32 bits or whatever until you are finished with the mix. Wavelab, and probably most other tools allow you to make dither part of the render process, but I seldom do that, I re-render my finished mix with dither as a separate step, and only if I am not sending it out for mastering.

And except for a really dense mix (think epic trailer track<G>), compare the dithered track with the original mix. There have been times when I the dithered track sounded the same, or different in a not-so-great way, and I've kept the original. For me, tracks with a really wide dynamic range, or lots of quiet passages benefit from dither. Denser tracks where there would be little opportunity to hear the noise anyway don't benefit, and sometimes I just like the original better. And that could very well be all in my head.

disclaimer - I do not master my own tracks, I have neither the experience nor the room nor the gear to do a proper job of mastering, and I always benefit from an objective second set of ears. That means I am much less likely to apply dither, since I want to allow the mastering engineer the maximum flexibility.


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## Tfis (Dec 13, 2017)




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## aaronventure (Dec 15, 2017)

WhiteNoiz said:


> http://productionadvice.co.uk/when-in-doubt-dither/
> http://productionadvice.co.uk/when-to-dither/
> http://productionadvice.co.uk/dither-or-distort/
> 
> ...




Great videos, exactly the ones that I wanted to post. All the answers to your questions are in there.

In short, yes, you should always dither on the export if you're rendering at lower than 32FP. Even if you're rendering at 32FP, if there is the slightest chance that the track will go through re-encoding or will be converted to MP3, put dither. As Ian demonstrates in the video above, even at 16bit it's basically non-audible. At 32FP you'll more likely hear the noise from your speakers caused by cables and A/C than dither. 

Dither is your friend and is present in every professional digital mix you've heard in your life.


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