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Best way to convert 24 bit mixes to 16 bit
Posted: Tue May 22, 2007 12:30 am
by waterstrum
Now that DP supports multiple bit rates within a project, I was wondering If I should mix my 24 bit project to a stereo 16 bit track within DP.
I usually make a 24 bit mix and convert it to 16 bits in Peak.
It never sounds as good as the original.
What have you folks found to be the best sounding way of converting a 24 bit mix to 16 bit?
What have you found to be the least disappointing method of conversion?
Thanks.
Posted: Tue May 22, 2007 3:51 am
by mhschmieder
Are you using POW-r dithering in Peak? If you haven't already upgraded to the Pro edition (it isn't available in LE), it is worth the upgrade price on its own.
I recently reconverted a bunch of 24-bit pre-masters to 16-bits using Peak Pro and POW-r dither, and can barely tell the difference. It used to be night and day, when I was using either DP on its own or in conjunction with Ozone's MBIT+ algorithm for noise-shaping (I forget where I did the actual dithering).
I have since downloaded the article as a PDF which I have both printed out and stored on my hard disc, but you should check the article linked at the BIAS website that compares SRC in a variety of apps.
To its credit, DP didn't fare as poorly as some of the other DAW's, but the real shocker was that the ONLY tools that came close to Peak Pro were Apple Audition (I think that's the one -- my refs aren't with me right now) and Pro Tools. BIAS Peak Pro still came out on top, but only slightly.
Sorry, it's late and I'm tired, so maybe I'm confusing which metrics the article showed, as it displayed charts for a lot of SRC's, so maybe that wasn't the article that also talked about POW-r dithering for bit depth conversions.
At any rate, it doesn't take much Googling to find reviews in top magazines, forums, informational websites, etc., that put POW-r dither on top. This is a licensed technology, so whatever you think of BIAS as a company or Peak as a product, POW-r dither is really a separate entity.
Posted: Wed May 23, 2007 12:00 am
by waterstrum
Thanks.
I have POW-R dither, but I wasn't using it.
I'll give it a go and let you know.
Posted: Wed May 23, 2007 12:24 am
by chrispick
Yeah, I use Peak Pro and POW-R dithering when down-rezing 24bit to 16bit. Always sounds pretty good to me, although I'll admit I don't have the most discerning ears for some of these subtleties.
Posted: Wed May 23, 2007 1:38 am
by HCMarkus
The other thing to keep in mind when going form 24 to 16 bits is make sure you are hitting close to digital zero. You are throwing away 8 bits of dynamic range, so be sure you are not wasting bits in the translation. Many folks use a plugin like Waves L1 or L2 to get levels up. You don't have to limit a lot unless you want to. L1 also offers Waves noise-shaped dithering.
Posted: Wed May 23, 2007 4:33 am
by mhschmieder
The dithering article and SRC article were from different sources, as I suspected.
Here is the URL for the excellent article on POW-R Dither, which BIAS licenses from Weiss Engineering:
http://www.proaudioreview.com/october99/Weiss-web.shtml
Amazing that the best dithering is eight years old... but not so amazing if you've followed the industry for a couple of decades, and are used to seeing how long it takes for innovative ideas to trickle down.
Posted: Wed May 23, 2007 7:27 am
by kenoflife
So is Pow-R dithering greatly superior to the dithering in Ozone?
Posted: Wed May 23, 2007 9:33 am
by mhschmieder
Yes. I did quite a few A/B tests a few weekends ago.
But as this is also somewhat subjective, use your own ears. POW-r dithering is more accurate, but that doesn't mean you'll like it better

.
Posted: Thu May 24, 2007 3:03 am
by waterstrum
I tried the Pow-r dither and it sounds pretty good.
When I put the 2 files up side by side and switch back and forth, I hear the soundstage collapse a bit.
There is a bit less precision, but it sounds O.K.
HCMarkus, this is premastering conversion.
Do you think the Waves L1/2 would do it better?
I'm wanting a 16 bit file that sounds exactly like the 24 bit file.
Posted: Thu May 24, 2007 5:20 am
by Phil O
If you go here:
http://www.24-96.net/dither/results.htm
you'll see that MegaBitMax blew away all the others. Anyone know about this shootout? Did they skew the test in MagaBit's favor, or is it a valid test? My understanding is that MagaBit is MBit's predecessor (used by Ozone).
It seems like Bob Katz really likes pow-r, but he's talking about a very expensive hardware version. Comments/opinions?
Phil
Posted: Fri May 25, 2007 1:42 am
by waterstrum
Hey Phil O,
That looks very persuasive.
I couldn't find MegaBitMax for sale anywhere, but if it works as an AU plug I will give it a try.
I just went back to my two file shootout.
I listened again and they sounded very similar.
One file had a slightly better sound.
It turns out the Pow-R file was the one with the bigger soundstage.
I had labled them ambiguosly and after checking my notes, I was very surprised to see this.
For now I will go with Pow-R.
Thanks
Posted: Fri May 25, 2007 7:24 am
by Phil O
waterstrum wrote:Hey Phil O,
That looks very persuasive.
Yes it does, but I don't know if the test was designed to yield those results or it's actually a valid test. I have Peak LE, but it doesn't have pow-r dither. I don't know if I want to spring for the upgrade for what might be a minimal improvement in dithering over what I already have. Hmmm. Does Bias have a full functioning demo?
I just went back to my two file shootout.
One file is pow-r. what is the second again?
Phil
Posted: Sat May 26, 2007 12:21 am
by waterstrum
I am comparing the original 24 bit mix to the Pow-r dither 16 bit version.
I will be using Pow-r from now on.
I'm very impressed.
Thanks mhschmieder.
Posted: Sat May 26, 2007 6:19 am
by giles117
Have you tried Barbabatch????
Posted: Sun May 27, 2007 1:57 am
by waterstrum
I have not tried Barbabatch.
I went to the website and it looks like a great product.
I'm not looking for a batch convertor, but if it sounds better, I would buy it.
The posted quality tests are for sample rate conversion.
I couldn't find any bit depth conversion comparisons.
I'm just looking for the best way down to 16 bits from 24 bits. (both at 44.1 khz)