Much thanks to you both, Dietz and David. Your comments are helpful.

david, AFAIK changing the username is not possible with the forum software ... i had to do that directly in the database.
christian

ps: you need to login with your new username now ...

There are four words guaranteed to start a brawl in a room full of mastering engineers. Three of them go together: "stereo miking techniques."

The other one is "dither."

And the differences between different flavors of dither are... well, let's put it this way: I believe in ridiculously expensive cable (within reason); I don't get excited about which kind of dither I'm using.

There, I've said it.

[6]

Ok Nick.

But some dithering algorithms produce audible artifacts when the audio is reprocessed and some other algorithms don't.

So, when I spoke about which dither to use its not because some sound better than others its more about whats going to happen to the audio after its been dithered.

If someone is producing a piece of music and the delivery format is 16/44.1 but is using higher bit depths during the production they should be aware of the fact that after delivering a 16/44.1 final audio file which has been dithered that it could cause artifacts if the mixing engineer decides to run some process on the audio.

Using the right algorithm in the first place could avoid this problem.

If you have some other info you can share to shed some light on the subject I would really love to hear it.

This is the way I have always thought about dither and its use.

I'm not a mastering engineer but I do come in contact with George Massenburg every now and then and will chat with him about it.

I look forward to hearing your comments.

David

Well, I'm the wrong person to ask, because I've never actually listened for the effects of multiple ditherings. I do know that Waves says something to the effect that [I forget which of the types they offer this was - i.e. not Type 1 normal] is designed for multiple ditherings because *in theory* the dithers could "stack up" (not their words) and cause problems...however they've never known that to happen.

In all honesty I can't think of a situation in my work in which this has come up - I've never had any reason to dither twice. I suppose it's possible with the older 16-bit VSL versions, though, since they must have been dithered from the original 24-bit recordings. Knowing VSL, however, I'm sure Dietz et al. thought of that and used the right dither.

In any case, I certainly don't want to be the one to argue that subtleties aren't important! My point is just that there are a few steps before you get to "Which dither do i use." [:)]

And I know George Massenberg will have an informed opinion about dither types, because he's way into this kind of thing.

@Another User said:

I suppose it's possible with the older 16-bit VSL versions, though, since they must have been dithered from the original 24-bit recordings. Knowing VSL, however, I'm sure Dietz et al. thought of that and used the right dither. [...]

It is no secret that you have to avoid noise-shaped dither like UV22 for signals that will receive further processing down the signal chain. And yes, we took care for that! [:)]

@Another User said:

If you do it by the book, you should always dither as soon you change the volume of a signal.

Well, I should rephrase that and say that I've never had to dither from 24 to 16 bits more than once - i.e. I wasn't talking about processors that dither from higher internal resolution (e.g. 56-bit accumulation) back to 24 bits. Dithering to 24 bits is never a user setting, as far as I know.

For my 2c thrown in here...

For the fact that 96k is going to more than half your processing power of your machine... I doubt that it is worth it.

Upscaling the VSL samples which are 44.1 to 96 will NOT improve their sound quality. They would only sound better if you got the original 96 *recordings*, which I guess VSL will release when it's technologically appropriate. Mixing 96k samples in 96k makes perfect sense, but upscaling to mix does not except for the point Dietz makes that the EQ's themselves sound better at this higher rate, I haven't tried this but it makes sense to me, anyway he's the expert [;)] the only thing with that is that you need a very powerful machine to do such a heavy mix at 96 so you probably woudn't be able to do a mix of that size at 96k anyway, so it's a bit of a catch 22 unless you run HD3. In that case, just stick to 44.1 - the native rate of the samples.

Miklos.

@Dietz said:

If you do it by the book, you should always dither as soon you change the volume of a signal.

Thanks for your comments Dietz. Question: I would think the DAW software would do this dithering internally anytime the gain is changed, true? And, intelligently with respect to how they do the summing (e.g., I think ProTools uses 48 bit summing path, so it seems possible that none of the gain changes require dithering until the final sum is presented back to the 24 bit path). In other words, I would not think that I need to add a dithering plug-in to each of my channels where I have set the gain to something other than unity or zero. Not sure if this is what you meant.

Pro Tools now has a dithered mixer - at least i assume that's the one they're using now. A few years ago there was a public outrcy saying that a dithered mixer was necessary, and Digidesign posted two mixers to see whether people could tell the difference. One dithered back to 24 bits the other didn't.

And I forget whether the results were conclusive, but I believe the one they use now is dithered. (I've been out of TDM world for a while and haven't kept up with this; much as I wanted to justify the upgrade to HD I just couldn't, so I sold my MIX system and for now just have an MBox that serves as a dongle for the PT software when I need it.)