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Post by Staffan Karlsson on Aug 29, 2019 23:12:08 GMT -6
So... When I do a mixdown, I go OTB, through my ”hardware chain of the day” and then back into Pro Tools on a stereo audio track. That file is obviously at the same resolution as the project, let’s say 24 bit 44.1 kHz.
Question. What would you do, to get the best possible result, when creating a dithered 16 bit file?
(Yes, I use dither when I do hardware inserts in Pro Tools cause it makes a huge difference in my opinion.)
Thanks
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Post by mrholmes on Aug 30, 2019 1:29:47 GMT -6
So... When I do a mixdown, I go OTB, through my ”hardware chain of the day” and then back into Pro Tools on a stereo audio track. That file is obviously at the same resolution as the project, let’s say 24 bit 44.1 kHz. Question. What would you do, to get the best possible result, when creating a dithered 16 bit file? (Yes, I use dither when I do hardware inserts in Pro Tools cause it makes a huge difference in my opinion.) Thanks As far as I understand it, most of the DA do not reach true 24BIT. You need to do 24BIT input dithering as soon you leave the DAW.
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Post by Staffan Karlsson on Aug 30, 2019 3:28:15 GMT -6
Yes I use dither every time I leave the DAW. It is very obvious why when you listen to the result. Any idea about my q?
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Post by mrholmes on Aug 30, 2019 4:45:15 GMT -6
There was a dither thread where Bob O went deep on dithering. I can hear it in blind AB others can't.
I do it each time and that's the end of the story for me.
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Post by Chad on Aug 30, 2019 6:29:32 GMT -6
I’ve been playing with Airwindows’ StudioTan and Not Just Another CD.
Both are great. I like StudioTan’s NJAD 24 for all 24 bit dithering, and NJACD for going to 16 Bit. (Chris from air windows describes NJACD as packing the quality of a 24 bit bit file down into a 16 bit file).
I was just in this process two weeks ago figuring out my system. Above is what I’m going to do pressing forward.
Hope this information is helpful in someway.
Chad
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Post by M57 on Aug 30, 2019 7:05:06 GMT -6
So when something like running a hardware compressor on a buss using Logic's I/O plug.. Is dithering necessary? And if it is, how would that work? ..how and where do I apply it?
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Post by stormymondays on Aug 30, 2019 7:11:39 GMT -6
So when something like running a hardware compressor on a buss using Logic's I/O plug.. Is dithering necessary? And if it is, how would that work? ..how and where do I apply it? According to some very smart people, it is necessary. Accordong to some other equally smart people, it's not. I have done my own test, with about 14 channels of external I/O, and using a couple different dedicated dither plugins. My DAW is Logic and my interface is RME. My conclusion is that it is not necessary. This also happens to agree with the designers of my daw and my interface.
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Post by M57 on Aug 30, 2019 7:26:36 GMT -6
According to some very smart people, it is necessary. According to some other equally smart people, it's not. How very politic of you. I'm using the Motu 828ES interface and I'm not aware of any internal dithering options that can be applied to its I/O ports. Similarly, I was thinking that the folks at Logic would have included dithering options on their I/O plug in if they thought it was necessary. I just started going OTB on my 2 buss recently, and I've been experimenting with using external hardware to re-print tracks here and there. Though I've always used dithering at the tail end of the 2 buss with Logic's Adaptive Limiter, that's it. I forgot to give thought to extra dithering when I started experimenting with a hybrid set-up. Glad this thread popped up.
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Post by swurveman on Aug 30, 2019 7:57:38 GMT -6
So when something like running a hardware compressor on a buss using Logic's I/O plug.. Is dithering necessary? And if it is, how would that work? ..how and where do I apply it? According to some very smart people, it is necessary. Accordong to some other equally smart people, it's not. I have done my own test, with about 14 channels of external I/O, and using a couple different dedicated dither plugins. My DAW is Logic and my interface is RME. My conclusion is that it is not necessary. This also happens to agree with the designers of my daw and my interface. It would be cool if there was something like what Ozone 8 has, where you can hear what is lost when you go from 44.1 to MP3.
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Post by svart on Aug 30, 2019 8:40:42 GMT -6
So when something like running a hardware compressor on a buss using Logic's I/O plug.. Is dithering necessary? And if it is, how would that work? ..how and where do I apply it? It's not a simple answer. I'm sure it's been covered before, but there are some facts about ADC conversion (applied to a sine for simplicity): In layman's terms, quantization error is when the signal value is at a transition point between two voltage steps in the A/D decision points and the A/D mis-codes the signal to the wrong value. This can happen due to system noise from active and passive components, voltage noise, or due to very small signal levels in comparison to general system noise. This error causes the encoded signal to have "jagged" code transitions that would equate to harmonic distortion if seen on a frequency spectrum diagram. Quantization error is a much bigger problem for small signals than large signals as large signals cleanly transition the A/D decision points, so it follows that it's a worse problem for higher frequencies. QE for large signals with fairly clean transitions is almost mathematically white noise. QE for small signals typically it manifests itself as odd harmonic content. Higher bit depths like 24 can have more significant errors than say 16 because the transition decision points are much closer together and thus more critical to get correct, which is also why higher bit depth converters need much cleaner clocking, I.E., a 24 bit converter with poor clocking or noisy design will have much worse QE than a 16 bit converter with the same clock signal or better design although it might not be apparent due to other issues. Now, here's where things get confusing.. If you're not already confused.. Most modern Sigma-Delta A/D converter chips use oversampling even if they don't expressly mention it. Most modern A/D chips need 32fs-256fs (32x-256x the sampling rate) clocks as they do oversampling and division internally to divide jitter as well as effectively "average" signals. Most of them also offer a hardware dither option as they typically internally run at a native bit depth which is typically the highest bit depth of the chip, I.E., 24 bit words will be dithered down to 16 bit outputs if the 24 bit part is set for 16 bit.. However, if we don't even consider the hardware dithering and only look at the oversampling, this averaging effect of oversampling (it's not true averaging though) has a similar effect of dither in that it's noise contribution is almost white. This is why most chips are now oversampling internally. There are vast benefits in terms of noise as well as accuracy and most of the time it negates external fixes such as software dithering. So to that end, I also don't think it's necessary to dither in software with modern converters as chances are high they are already dithering in hardware, or oversampling/averaging is doing a similar job. Now, why do some folks think it's helping? Software dither doesn't know the difference between A/D QE issues and harmonic products from analog gear and encoded into the signal. The A/D will encode whatever it sees, so if there are low level harmonics being encoded, or if the A/D is creating QE, the result is that the datastream will have small amounts of harmonics on it and they won't be distinguishable from each other, at least as far as software is concerned. Take the 1176 for instance, which is notorious for it's "sound", which I've found to create a lot of harmonics even when in bypass.. Simply running signal through the amplifiers inside impart a great deal of distortion, but that's also part of it's sound. Applying software dither to an insert return with an 1176 is effectively "helping" to remove some of this harmonic content and "smoothing" it out, and since we know that it must be small signal content that the dither is working on, the effect is similar to mathematically low-passing a signal. It turns a rougher sound into a more pleasing sound by filtering harmonic content, especially the high frequency stuff that we routinely find "grating" to the ears. Same effect as when someone says "low pass everything in the mix to clean it up". But then again, we also use loads of EQ and filtering to get rid of harmonic content anyway, so what's the difference if they both do something useful? Anyway, to answer OP, I use Izotope 64 bit dither and sample rate converters. They definitely sound better donwconverting 24/88 to 16/44 than simply tracking at 16/44, but I only use them to create lower bit depth/rate tracks for delivery. I don't dither on I/O.
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Post by wiz on Aug 30, 2019 16:35:22 GMT -6
I use logic.
I dither on all I/O by putting air windows dither in the plug in slot prior to the IO plug in
I did tests and it made a difference to me.
Cheers
Wiz
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Post by kcatthedog on Aug 30, 2019 17:13:54 GMT -6
Just curious, as I thought dithering only theoretically mattered, if the digital word length was being shortened, e.g 24=>16?
If not, if 24=24, how does dithering benefit ?
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Post by M57 on Aug 30, 2019 17:39:03 GMT -6
I use logic. I dither on all I/O by putting air windows dither in the plug in slot prior to the IO plug in I did tests and it made a difference to me. Cheers Wiz Which air windows dither?? The first one on his site is DitherFloat.
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Post by wiz on Aug 30, 2019 17:53:50 GMT -6
I use logic. I dither on all I/O by putting air windows dither in the plug in slot prior to the IO plug in I did tests and it made a difference to me. Cheers Wiz Which air windows dither?? The first one on his site is DitherFloat. Airwindows
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Post by Chad on Aug 30, 2019 18:27:41 GMT -6
I use logic. I dither on all I/O by putting air windows dither in the plug in slot prior to the IO plug in I did tests and it made a difference to me. Cheers Wiz Which air windows dither?? The first one on his site is DitherFloat. M57, I researched this a couple of weeks back. The two "latest & greatest" (according to my findings, wading through his blogs) are these: » STUDIO TAN: This has 3 options, each in 24 + 16 bit. If you only download this plugin, you're covered. » NOT JUST ANOTHER CD: This one is Chris's "premier" dither for a 16 bit destination (again, according to my several hours of research on a Sunday night). He said that his goal was to squeeze 24 bits of goodness into 16 bits. Those are the only ones I'm planning to use at this point. Chad
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Post by svart on Aug 30, 2019 19:25:19 GMT -6
Just curious, as I thought dithering only theoretically mattered, if the digital word length was being shortened, e.g 24=>16? If not, if 24=24, how does dithering benefit ? The algorithms are doing *something*, but their methods are generally proprietary. We know that dither should be a small amount of frequency and level dependant filtered noise added to a signal to "smooth" over abrupt code (voltage in the real world) steps, so their code must do something to recognize these steps and then apply an appropriate amount of noise. Too much and your noise floor will go up quite a bit and your signal will "smear" like a large amount of jitter was applied. Honestly, I'm still not sold that people don't like a small amount of jitter in converters. It makes things a little more organic and gelled sounding a long as there's not so much that it makes it sound like a wet blanket over the speakers.. But I think the effect is that dither applied, even if it's not truly *needed* gives the signal a smoother and more analog feel.
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Post by mulmany on Aug 30, 2019 19:42:44 GMT -6
Isn't the argument for using dither on your dac because internal daw processing is 32bit but you need to convert down to 24bit so the dac can process it?
For me I found dither on the output of my daw inserts to really help smooth things out and help gel the mix together. I mix at 24/96k.
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Post by svart on Aug 30, 2019 20:12:45 GMT -6
Isn't the argument for using dither on your dac because internal daw processing is 32bit but you need to convert down to 24bit so the dac can process it? For me I found dither on the output of my daw inserts to really help smooth things out and help gel the mix together. I mix at 24/96k. Dither is for the acquired and codified signal from the a/d. It's also for reducing bit depths. If you have 24 steps, but remove 8 of them to get down to 16, some of the transitions will be much greater, so the algorithms need to mathematically interpolate and recode some steps, and then apply dither to smooth it all out. This is different and separate from the analogous analog "reconstruction" filter on the dac outputs which averages the stepped voltage pulses and smoothes the transitioning between steps.
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Post by Staffan Karlsson on Aug 30, 2019 22:26:46 GMT -6
All very fine. However not the answers to my question. How do I dither a 24 bit file when I change it from 24 to 16?
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Post by kcatthedog on Aug 30, 2019 23:00:47 GMT -6
i Think they were answering my question? Somewhere in your daws output process you can select a dithering algorithm, probably more than one option just pick one that dithers 26 to 16 bit.
What daw do you use ?
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Post by M57 on Aug 31, 2019 4:24:55 GMT -6
i Think they were answering my question? Somewhere in your daws output process you can select a dithering algorithm, probably more than one option just pick one that dithers 26 to 16 bit. What daw do you use ? Staffan said he uses PT in is original post. Surely PT has multiple dither options when bouncing/printing?
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Post by mulmany on Aug 31, 2019 5:56:34 GMT -6
All very fine. However not the answers to my question. How do I dither a 24 bit file when I change it from 24 to 16? I use the PSP dither plug on the master when I bounce down my mix. As far as I know PT does not automatically apply dither.
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Post by cyrano on Aug 31, 2019 5:56:46 GMT -6
All very fine. However not the answers to my question. How do I dither a 24 bit file when I change it from 24 to 16? In this case, there's no need for dither, as truncating to 16 bits is supposed to be bitperfect. Besides, any DAW on the planet does dithering when needed, eg when producing the final render. Some have some options, like the algorithm to use. There's only a few choices, unless you go to taste country. But that's not dithering an sich. The difference between algorithms is very subtle. I've never been able to hear it. See if you can hear it?
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Post by cyrano on Aug 31, 2019 6:01:21 GMT -6
Protools dithers, like any other DAW. The only question is "when does it dither". I'm pretty certain it dithers when you render final output. But I also remember there's an entire chapter about when it dithers and when not in the manual. Dithering twice usually doesn't sound good to me.
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Post by mulmany on Aug 31, 2019 6:06:20 GMT -6
Protools dithers, like any other DAW. The only question is "when does it dither". I'm pretty certain it dithers when you render final output. But I also remember there's an entire chapter about when it dithers and when not in the manual. Dithering twice usually doesn't sound good to me. Check that again... PT does not dither when using the bounce to disc function. This is the sticky part and why everyone gets all confused. You need all the parameters laid out. PT does apply dither when you import/export a file!
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