TL;DW: Sort of airy compressed-y dither
Spatialize is one of my high-performance boutique dithers. It’s not as good as NJAD or Dark, but it’s got some neat tricks, and what it excels at is focus.
This modified dither algorithm has opinions about what ought to be randomized. Any normal dither (especially a technically correct TPDF-based one, such as PaulDither, TapeDither or NodeDither that can encompass either) has no preferences about what samples it gets. It will apply noise regardless, with perfect impartiality.
Spatialize (which I’ve also termed Contingent Dither, early in its development) isn’t like that. It says, ‘hey, this sample is exactly on a quantization value. No way am I going to mess that up, it’s staying right where it is!’. Or, it says ‘this sample is exactly between two quantization values. If I rapidly flip between adjacent values I can try to get the DAC to produce output between them. What could go wrong?’. Or, it says ‘this sample is none of the above, let’s bring in some randomness and apply dither like some normal plugin that isn’t crazy, would do’.
Or all of the above, blended…
That’s how Spatialize works. These are pretty bold things to try to do, especially the attempt to balance between two quantization values: that’s not really a reasonable thing to try, even when blended with random noise. And it pays something of a price: while Spatialize is quiet in its noise generation even without resorting to noise shaping, its behavior down around the noise floor isn’t perfectly well-behaved.
But that’s a trade-off, because by sacrificing this good behavior, Spatialize gets to be very sure that when samples hit perfectly on quantization boundaries, they’ll be accurately represented. And the bit-flippiness of the exactly-between behavior gives rise to a really strong highpassy effect that heightens treble energy. The result is a dither with a holographic, intense sonic reality to it: and it IS reality, because it comes out of this determination to honor the true values of the samples wherever possible. Spatialize is always prepared to abandon ‘appropriate’ noise floor behavior if it can nail down the sonic envelope with more ruthless accuracy.
So, if you’re into the hyper-real, high-definition sound of extreme clarity and accuracy, Spatialize might be your preferred Airwindows boutique dither. And, since it does it all with no noise shaping, there’s still an ease and naturalness to the resulting sound.
And since this is Redux, you can now have it with a switch between 24 and 16 bit operation, and the DeRez control both to monitor its noise floor behavior, and to use it for bit-crushing. It’ll be weird because of the extreme compressed quality it gets at the noise floor, but hey, another option!
Oh, one more thing…
As I said in the video, everything on my website from ten years of making AU plugins is now downloadable. When you download the ‘demo’ and open the disk image, it’ll be the full versions. (there are exceptions that I simply didn’t have on hand, mostly from around 2015 when times were hard.) If you download a .dmg (Audio Units only, Airwindows VSTs didn’t exist then) and the plugins inside don’t say ‘demo’ in the name, those are the real ones. :)
I got most of ’em. And it’s Patreon that got me this far, to where I could do this because I’ve re-released pretty nearly everything as AU/VST open source anyhow. So, now I get to give back, even more than before. Talk to ya on the Monday Q&A!