Airwindows

Dattorro

TL;DW: Dattorro is the resonant lowpass filter out of Donut.

Dattorro.zip (496k) standalone(AU, VST2)
Dattorro in Airwindows Consolidated (a separate project) under ‘Filter’ (CLAP, AU, VST3, LV2)

Here’s the filter out of Donut! This started as an experiment to see if I could code an SVF. That’s a State Variable filter, and now that the other plugin makers have stopped laughing I’ll tell you what it is :)

Turns out a State Variable filter is about the simplest way you can do biquad-filter-like things (read: controllable and flexible) and plugin devs really like this one. That includes heavyweight genius devs like Andy from Cytomic who made The Glue and The Drop (Andy is a ‘model every component’ guy doing stuff I choose not to do, a rigorous circuit modeler). Dattorro is not that: Dattorro is me taking the concept of the state variable filter and doing Airwindowsy things with it.

For instance, the frequency control’s designed to go right up to the high frequency limit of the filter no matter what sample rate it’s running under. It does this not by restricting the max frequency, but by altering the logarithm taper of the control so midrange frequencies will always be roughly in the middle of the control’s travel. That means you never see exactly what frequency you’re using, but neither do you see it on a 303 or x0xb0x and those are great, and this is very much a synth style filter.

There’s code for every kind of SVF inside Dattorro’s source code, commented out, but the lowpass you get (and the resonant behavior, it has a great reso flavor) is not stock SVF, but airwindowsized. That’s because I’m using a sin() function in there (for code simplicity. PurestSaturation would work just as well for this, or TapeHack) but not in the way you’d think. The obvious thing to do is put it on as a post clipper for simply adding distortion.

But you know I’m always interested in anti-saturation, and so the softclip is going on the bandpass output… which is then SUBTRACTED from the lowpass (well, 0.5 of bandpass into sin() and then subtracted, I was working out what sounded best) and that’s the filter. It’s nearly as simple as the stock SVF but it sounds way, way slicker and that’s what’s in Donut and now here it is as a standalone filter for you.

The sound is like the filtered-out part gets deeper and more vivid and interesting. Applying inverted saturation is like expansion: it’s part of Dubly, and is like inverse Density, and is the buss section of every Console plugin in one way or another. It makes stuff sound farther away. Applying it to a synth filter in this way gives sonic depth and also a curious side-effect: the rolloff actually got shallower, even when it’s resonant.

This might be a clue towards something that could make a better Baxandall-style filter. I’ll keep experimenting. Enjoy Dattorro :)

Airwindows Consolidated Download
Most recent VCV Rack Module
download 64 Bit Windows VSTs.zip
download Signed M1/Intel Mac AUs.dmg
download Signed M1/Intel Mac VSTs.dmg
download LinuxVSTs.zip
download LinuxARMVSTs.zip for the Pi
download Retro 32 Bit Windows VSTs.zip
download Retro PPC/32/64 Mac AUs.zip
download Retro PPC/32/64 Mac VSTs.zip
Mediafire Backup of all downloads
All this is free and open source under the MIT license, brought to you by my Patreon.

Date March 29, 2026
Author Chris
Comments 1 Comment

ToTape9

TL;DW: ToTape9 is Airwindows tape emulation and brightness compression.

ToTape9.zip (810k) standalone(AU, VST2)
ToTape9 in Airwindows Consolidated (a separate project) under ‘Tape’ (CLAP, AU, VST3, LV2)

ToTape is one of the most successful plugins I’ve ever had. Step by step, it’s come along and incorporated more and more things, but always in an original way. It picked up flutter, bias, Dubly, and then adapted all these things to the needs of the musician. So if you don’t know how to calibrate Dubly units for heavy music, you have a Tilt that will give you more of a leaning towards brightness, or darkness… but it’s implemented via the Dubly controls so it acts like adjustments on a tape machine. Shape works likewise, going for either more old-school sonority or more big-studio chill. Flutter behaves itself unless you don’t want it to, and the input and output controls make it very simple to manage ToTape9’s gain staging, for gentle use or aggressive slam.

But then the heart of ToTape is completely replaced by what I learned making TapeHack2, itself a giant leap over the original TapeHack, which was itself a huge discovery. When I tried this in the guts of ToTape I was just completely shocked by how huge it sounded. The scale of the sound put the previous version to shame. You do not have to slam this to have it sound amazing, but if slamming’s your thing I think this will bring delight and joy.

And then it’s topped off by not the latest ClipOnly… but the NEXT ClipOnly. The one where I ran with the concept, not completely unlike my old Chrome Oxide plugin but in a new perspective, of ‘dithering aliasing’. It turns out you can’t actually dither aliasing but there’s a large number of interesting effects you can produce by noising up clipping. So when I experimented, I ended up applying it in a way nobody else was doing, introducing noise just faintly as clipping begins to happen, ramping it up, and then as hard clipping takes over, shifting it to the ‘edge samples’ akin to what ClipOnly and ClipOnly2 have always done, meaning the noise goes back away again (and is never all that loud: sorry, no special FX here)

And combining this with the existing ClipOnly2 created a monster.

So that’s what’s on the end of ToTape9. Output at 0.5 means you’re just barely bumping this final clip stage. Boost it and you’re hitting the output clip harder, cut it back and it’s purely the ToTape section. I would imagine mostly leaving it at 0.5 is what most people will do, but it’s yours to experiment with. It produces a ‘beyond tape slam’ that is shockingly big and deep and loud, it applies its work only when clipping is actively happening, it’s all within a very tiny amplitude window so it stays clean on most everything, and it gracefully handles Gibbs effect overslew (intersample clipping) without ever applying upsampling or downsampling, so the sound is aggressive and raw the way I like my tape effects to be.

Try ToTape9. It’s the most intensely tapey plugin I’ve ever done, with new abilities like the ability to soak up highs like the real thing. It’s got all the little details you could ask of a no-compromises real tape model, but adapted to musical purposes so you can think ’tilt towards more brightness’ rather than ‘should I go with a 355 nanoWebers per meter calibration’. And it’s got the most killer output clip stage I’ve ever made, just to let you use it as a kind of loudness maximizer right out of the box.

I hope this brightens your day :)

Airwindows Consolidated Download
Most recent VCV Rack Module
download 64 Bit Windows VSTs.zip
download Signed M1/Intel Mac AUs.dmg
download Signed M1/Intel Mac VSTs.dmg
download LinuxVSTs.zip
download LinuxARMVSTs.zip for the Pi
download Retro 32 Bit Windows VSTs.zip
download Retro PPC/32/64 Mac AUs.zip
download Retro PPC/32/64 Mac VSTs.zip
Mediafire Backup of all downloads
All this is free and open source under the MIT license, brought to you by my Patreon.

Date March 22, 2026
Author Chris
Comments 7 Comments

Donut

TL;DW: Donut is in memory of Dilla.

Donut.zip (511k) standalone(AU, VST2)
Donut in Airwindows Consolidated (a separate project) under ‘Filter’ (CLAP, AU, VST3, LV2)

The main reason for this plugin is, one of my livestream people has wanted it for a long time. I’m hoping this brings him joy?

Thing is, I’ve made a plugin in the SPIRIT of what I hear in Dilla, not a clone of a particular effect he may or may not have used on various things. And so, I believe this can be set up to do numerous things you’ve heard Dilla do… but also, I took pains to help it do other stuff I heard, and it kinda went on from there.

This is basically an envelope follower. It’s like my newest compressor plugin (as in, not out by itself yet but the one that’s in ConsoleH and ConsoleX2), but instead of modulating volume, it modulates a lowpass filter. Except it’s not just ‘a lowpass filter’, it’s me trying out a very popular version of those filters known as a state variable filter, and doing some experiments with it which I don’t know how common they are, but I loved the sound I got when I did them. The filter will come out by itself too, it’s called Dattorro after the guy who wrote it into a textbook, and it’s going to do interesting things like help me make a formant filter, later.

But the way it works NOW is, you’ve got the compressor (a Bezier-filter compressor, so it doesn’t have attack speed artifacts) with an attack speed that basically has it act like the original BeziComp, and then a release speed that lets you slow it right down. If you want to hear where it’s at, you can turn the resonance up until it’s basically just a wavering note.

Then, there’s a filter cutoff, a resonance control, and two more sliders just below those which modulate them according to the envelope, and that’s it.

If you put the filter in the middle, you can see that the modulator is at zero when in the center. So you can subtract the envelope, OR add it. Same with the resonance. My hope is that this can get you some neat effects, perhaps using Dilla-esque techniques like splitting the tracks and applying this real aggressively to only certain parts. In no way is it a ‘push butan for dilla FX’, my hope is that it’s flexible enough to do a wide range of things with. Remember, if you use a very slow attack and fast release it’s more of a BeziComp response, very wiggly.

Part of what I found was that Dilla, I think, liked to run stuff into his Moog to process. Donut can do some of that: sweep it low and give it the right amount of resonance and it ought to resynthesize bass real well. It should handle automation nicely: state variable filters are better at that than, for instance, biquads. This is not the steepest of filters, but I set it up to have tone while reshaping things.

I hope you like Donut! I have many things to put out but I can put out Dattorro too, if you like. That one comes with debugged versions of the original SVF code (which didn’t work perfectly right out of the box, but has more options than I use here)

Airwindows Consolidated Download
Most recent VCV Rack Module
download 64 Bit Windows VSTs.zip
download Signed M1/Intel Mac AUs.dmg
download Signed M1/Intel Mac VSTs.dmg
download LinuxVSTs.zip
download LinuxARMVSTs.zip for the Pi
download Retro 32 Bit Windows VSTs.zip
download Retro PPC/32/64 Mac AUs.zip
download Retro PPC/32/64 Mac VSTs.zip
Mediafire Backup of all downloads
All this is free and open source under the MIT license, brought to you by my Patreon.

Date March 15, 2026
Author Chris
Comments 4 Comments

Slew4

TL;DW: Slew4 is tape compression without the tape, for brightness control.

Slew4.zip (542k) standalone(AU, VST2)
Slew4 in Airwindows Consolidated (a separate project) under ‘Brightness’ (CLAP, AU, VST3, LV2)

You’ve heard of a cat without a grin and a grin without a cat, and you’ve heard of plenty of tape plugins without tape compression… but how about the compression without the tape?

Slew4 does just one thing, but it does it incredibly well. It finds digital edges and glare and high frequency tizz, and it wipes out JUST that, to whatever extent you like, using new filtering ideas I don’t think have been used before in this way. The Airwindows Slew plugins have long been a secret weapon for just this purpose, but this takes it completely beyond anything I had.

That’s why this is the technology in TapeHack2, and what got included in ConsoleH and ConsoleX2 as hasty updates soon after they came out, and why it’s a significant part of ToTape9 which I’m doing everything I can to finish up. Now it’s there for you to use and control, without any sort of saturation stage or any other sort of tape modeling, in its purest possible form.

One thing that means is, if your sound isn’t bright enough, there is no chance you’ll ever hear it do anything. With the right kind of vocal track this is a de-esser all by itself. For other vocal tracks, even ones with pronounced esses, you’ll find it does absolutely nothing. It ONLY cares about the very highest highs, and excises them so neatly you’d never know they were there.

Slew4 runs two samples of lookahead to do what it does, and makes its filter by stacking up averaging filters with even numbers of samples in them. These produce stopbands with big cancellation nodes in them, but when you stack them up, each new cancellation node targets a bump (between nodes) from the previous one… so it becomes a very steep roll-off with good filtering past the cutoff, and no pre-ripple meaning it has incredible time domain performance for something that steep. The strangeness of the stop-band response is probably why this wouldn’t have found use before, but it turns out to sound fantastic, especially when it’s just reining in the highest highs without touching anything else.

If you liked TapeHack2, you already like this! Enjoy playing with it as a dedicated brightness tamer :)

Airwindows Consolidated Download
Most recent VCV Rack Module
download 64 Bit Windows VSTs.zip
download Signed M1/Intel Mac AUs.dmg
download Signed M1/Intel Mac VSTs.dmg
download LinuxVSTs.zip
download LinuxARMVSTs.zip for the Pi
download Retro 32 Bit Windows VSTs.zip
download Retro PPC/32/64 Mac AUs.zip
download Retro PPC/32/64 Mac VSTs.zip
Mediafire Backup of all downloads
All this is free and open source under the MIT license, brought to you by my Patreon.

Date March 8, 2026
Author Chris
Comments 5 Comments

Chris

Dattorro

ToTape9

Donut

Slew4

human-made bespoke digital audio

Kinds Of Things

The Last Year

Patreon Promo Club