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Airwindows is one guy: me! I am an audio hacker and computer programmer from way back. I seek only to continue my life up here in Vermont, inventing things and putting them onto the internet, sometimes for free and sometimes for pay. My hope is that people richer than me (i.e. most people) don't rob me. My other hope is for another cup of Aeropress. One out of two ain't bad!


TL;DW: A weird digital ambience!


For all that we try to make plugins have natural, acoustic or electric, retro vibe qualities, sometimes there’s a thing which breaks the rules by creating a distinctive voice that has nothing to do with naturalness. I’ve got an old Alesis reverb like that: very primitive, but deep as anything. There have always been odd little boxes with a style all their own, like the Delta Labs Effectron, which is low-fi but uses delta-sigma modulation like an SACD (but much more crudely!)

In that spirit, here’s StarChild. The inspiration came from the old Ursa Major Space Station. That said, StarChild sounds nothing like a Space Station, but it does sound like it’s out of this world. Like Space Station, it produces series of echo taps which aren’t perfectly regular. Space Station has little rhythms that it does, while StarChild works on prime number sequences: that produces a sputtery sort of delay line in which it won’t reinforce any one frequency.

What you get is a curious delay/ambience effect, in stereo (it’ll widen stuff that’s only in the middle). It can work kind of like a natural ambience that’s a room in a horrible shape, or you can crank out the duration and get weird stretched textures with a variety of granularity. It’s an odd little plugin: didn’t sell that well in its earlier incarnation, yet this revised newer form is hotly anticipated: a bunch of people really started wanting it when Kagi (my payment processor) went out of business and suddenly it couldn’t be sold.

Now that doesn’t matter, because I’m using my Patreon to live on (granted, it’s sort of crisis mode but it will grow in time) and the plugins are being given away for free. I hope you enjoy it. If the Patreon reaches $800 a month, I will begin open sourcing the plugins one by one, and StarChild could be one of those plugins. (Please, stay within an order of magnitude or so of the $1-$2 that the Patreon is designed to ask: I have no wish to depend on individuals giving… or withholding… vast sums just by themselves)

I hope you like StarChild. I know quite a few people who eagerly awaited this one.


TL;DW: Distinctive analog coloration.


Though I’ve put out BussColors to mimic existing audio hardware, it was always my intention to create analog-ifying plugins that weren’t about cloning existing gear: that produced their own distinctive sound. The first Desk plugins (Desk, TransDesk, TubeDesk) were made in this way, using audio DSP which isn’t typical.

As this line of experimentation evolved, it led me to what we’ve got here. Desk4 is the latest refinement of the Desk line, now for Mac and PC VST (as well as AU)… and free.

The drive control is a boost as you might expect. Turn it up for more slam and dirt. It’s very soft, textured, rich-in-nutrients dirt, but it’s basically ‘distortion’.

Treble Choke is more unusual: don’t overcrank this control or you’ll generate artifacts such as uncontrolled DC. It’s not a normal algorithm and not a traditional EQ or even a saturation: as you can tell from the weird behavior when you crank it. Use it subtly and you’ll have a brightness conditioner not found outside quality analog gear. Since it’s a plugin, you can also push the extremes of the behavior, just don’t get too carried away. It’s designed to let you break it with extreme settings, so it’ll be flexible across different kinds of audio.

The power sag and frequency controls are the heart of some behaviors in the earlier TubeDesk and TransDesk: you can make your imaginary analog hardware overload its power supply. Cranking the frequency slider moves the area of interest down, for tube power supply sag behaviors. Tiny settings work over a tiny range of samples, causing the effect to hit higher frequencies. If you hear an obvious effect, you’re probably applying too much… unless you intentionally want to crap out the audio, in which case this is a uniquely aggressive way of doing that. It’ll add grunge in an entirely different way from simple distortion, so you can do both.

These things are made possible by my Patreon. If I get it to more than $800 a month, I’ll begin open-sourcing these plugins, and that’ll open up the world of plugins in a whole new way. I’ll also make available my templates so that people can more easily begin coding their own stuff (which doesn’t mean it will BE easy, but it’s a way to help new coders and people like me who have more DSP ideas than systems coding expertise). Currently, I’m putting out one a month from my Greatest Hits list, an extra from the more obscure and unsung end of that list, plus additional plugins out of my library of successful AU plugins.

Also, if the Patreon gets some more patrons (not money so much as just new patrons), I can appear in the top 50 of’s Gamer charts! I’m currently at 51 on that list, and it’s possible being more visible would help me and Airwindows, so I’m excited to see what’ll happen there! I will be by far the lowest income creator on that top 50, because I give people more while asking less. But it’ll be great fun to know I’m in the top 50 of something Patreon-related :)


TL;DW: Just a special treble-erode noise.


Sometimes it’s good to have just a little specialty plugin that does a useful thing. Hard to do that in the commercial plugin biz, where everything has to be the biggest hype to date: but hey! Thanks to Patreon I’m free of all that, and can follow my vision.

It helps that I put out a lot of plugins: it’d be weird to do this as my only plugin for the month. But, while I work on Desk4 and StarChild from the greatest-hits list, I thought I’d sprinkle a little TapeDust for you.

This is slightly different from the tape noise in Iron Oxide, though it’s the same general principle. It is a slew noise plugin. What that means is, the noise ONLY hits high frequencies or anywhere the signal’s moving rapidly (there’s a teeny bit of other noise added at high settings, but it’s mostly that).

Note the ‘or anywhere the signal’s moving rapidly’. This isn’t a crossover. If you put in a sine wave that’s low and loud, you’ll get very obvious noise only as it crosses through zero, and that’ll sound odd. In general, cranking this up is weird. It’ll depend hugely on what kind of signal you’ve got… but that’s the beauty of it if you can master where to use this plugin.

Basses? Probably no way. Full mix? Getouttahere, no chance outside very low settings. Guitar? Hmmm. Drums, loops? A pattern emerges.

TapeDust can convert ugly sharp treble attacks on pointy percussive atonal sounds to pretty much any degree of dense, noisy, natural-sounding crunch. It’s a type of noise, so it also gives analog-style variance to repeated samples that might sound over-digital. And the less tonal, or the less ‘pure clear note’ the signal is, the more TapeDust you can get away with. Since it’s a slew noise, it hits the treble of your signal HARD, but since it’s a noise, it’s not filtering or softening the sound as much as it’s just eroding it, weathering it, making it more natural. Anywhere you’ve got bright highs on a nonpure sound, you can grind them off with TapeDust.

Of course, if you’re cool with using super-low settings, you can do that anywhere: it’s just important to register that this very specialized and dedicated tool is super picky about what it likes to work on. It’s a beautiful example of taking your production skills deeper: use something that can sound horrible and wrong, and find places where it’s in its element. You can do outlandish textural things, taking something like a clean electro mix with deep clean bass, and sticking heavy TapeDust on just one element in the mix to contrast with the un-grungy elements. I hope you like TapeDust. It’s the kind of plugin I love to make.


TL;DW: A minimalist analog tape emulation.


Here’s something more… refined.

FromTape was originally conceived as a ‘bump-less’ ToTape. It appeared with the original ToTape, and then with ToTape3, as a stripped-down version without the head bump, intended as very much the same thing but less bass. In some ways that’s still true.

But, as ToTape grew to version 5, it developed many unusual traits. There was always that untameable head bump code, and its desire to throw DC everywhere (ToTape’s head bump literally doesn’t want to settle on 0, it wants to be either a positive or negative offset voltage by preference). There was the flutter. There was the built-in highpass, coded in a curious way to get a resonant quality around the corner frequency without any actual resonance applied. ToTape grew into a rich and strange effect, with many curious qualities and many fervent fans. And it’s out.

And then there was FromTape.

This FromTape draws on what I’d learned from the Purest plugins. It’s like no previous FromTape: elements have been rearranged, deleted, rethought until it became just this: the ‘unusual’ highpass (which accumulates tiny alterations in a buffer and then applies them in a single add for purity reasons) and THEN the Softer control, accentuated, but ONLY the Softer code and not the ‘Airwindows saturation’ that’s a major part of ToTape and allows for the ‘tape drive’ and saturation effects. The highpass is called ‘Weight’ and wired backwards so as you increase it, more bass comes out.

So, this new FromTape does the very transparent treble softening, but has no real ‘distortion level’ because it has no distortion outside of Softer. It has the highpass (over a far broader range, and adjustable) but not the head bump the highpass was designed to handle. Instead of going after the other effects, the highpass goes first, and then the Softer works on the output of that.

It’s capable of clipping to a set level only if Soften is cranked totally, and then it’s not a good sound (still available, though, in case you want it). Anything else will let peaks through largely undiminished. The highpass cuts bass, but in such a way that clean unclipped bass pre-FromTape might well turn into over 0dB output after FromTape: it cuts the bass in such a way that it might end up 3dB louder. Go figure, use the output level control to buffer it. Rather than loudenating stuff by ‘slamming it with tape saturation’ it’s more likely to reshape the tonality of the sound so it sounds quieter for whatever peak level you’re reaching.

It sounds amazing. It’s also way more CPU-efficient than ToTape, and eats much less in terms of delay buffers and things. You could use it everywhere, certainly on channels where ToTape would be too heavy, but even on channels plus the 2-buss. You could use it in mastering if you wanted to soften digital edge while retaining total clarity, or if you wanted to take an overlimited mix and make the bass rounder and more open, giving a little crest factor back.

I got lucky. FromTape sounds amazing, it really came together in a surprising way. You might like the added thickness and fullness of ToTape, or the bells and whistles, but if you want to call FromTape superior, you won’t be seeing an argument from me. Surprise! This might be your new best tape plugin, especially if you like subtlety and have ears like a bat.

Wouldn’t exist without Patreon. I think it’s possible that I’ll reach the $700 goal this month, and if I do, you get not only Desk next month, you also get my pick of the ‘end of the list’ (stuff that sold less than what the Patreon’s currently at), and I think I will pick StarChild first, just FYI. So, let’s go $700, and I do have something lined up for next week, as well :)


TL;DW: Soften headset mic recordings that have been super hard clipped on capture.


I hope this is handy for somebody: I made it for myself. The idea is, if you’re a youtuber or something and have the ability to post-process your mic feed, you might have it set up so normal levels give a normal sound, but then if some monster jumps out and KILLS you in your video game, you might scream very loudly into your mic and blow the recording into ridiculously loud clipping.

This does several things. Firstly, it clips and softens those moments further and tries to suppress some of the highs you got from the super-hard clipping. Secondly, it’s got a highpass which can subdue thumps and pops, and can also be used in conjunction with something like a pitch shifter to give cartoony voices (I’ve tried this with DiracFxAU, now known as zynaptiq: only used their demo AU, didn’t use their library in anything code-wise and won’t be doing so as they are unaffordable). I found highpassing before the pitch processing was very helpful for toon voices of that type.

This isn’t the seriousest of plugins, but I’ve seen people ask me for it, so now it’s free and Mac/PC VST too. I think it’s best confined to its intended use, processing single voice tracks that have wildly distorted moments. If you try to use it on the 2-buss I will be very cross with you ;)

I’ve been doing all this work supported by Patreon, which is to say supported by those of you who are able to toss me a buck a month or so. Patreon itself doesn’t do a thing to find people who’ll help me: they’re simply another sort of payment processor. So if you can do $12 a year or find more people who think that’s a good investment to have a Chris From Airwindows continually thinking up new free stuff to give you, I greatly appreciate it. This appreciation is usually shown in the form of plugins, but when I have other stuff to also offer, I’ll let you know what’s brewing in the secret airwindows vats of awesomeness ;) and yes, something is brewing beyond plugins and you’ll be hearing about it before another year is out. And I don’t even mean the Axoloti, but I’m very excited about that hardware platform too :)


TL;DW: The highest quality Airwindows analog tape emulation.


ToTape5 is the best Airwindows analog tape emulation. It builds upon the previous four versions (which have been some of my best sellers) and incorporates everything learned from the Purest series of plugins, to produce a tape emulation that does what analog does. (Analog tape does really good things for mixes, and it’s very difficult to get it right without sinking into a morass of overprocessing and digital blandness)

It’s better than Iron Oxide, always was. Iron Oxide is for ‘slamming tape for effect’, for putting on individual tracks, not realism. ToTape is for realism and quality: for ‘mixing to tape’, in the box. I don’t think there is anything else that can stand as much scrutiny as ToTape will: it’s developed on mastering-grade gear and when used in its most optimized state, it’s not a toy. It should be more transparent and musical than most plugins (never mind ‘tape emulation’ plugins, which are generally not even as transparent and musical as a good digital EQ plugin).

It has six controls: four if you don’t count Output and Dry/Wet, which are pretty obvious.

Louder defaults to 0.25 because the tape emulation soaks up some level. You can set it to 0 for added purity (it removes a gain trim stage if you do) and if you do that, you can plainly hear that the emulated tape ‘soaks up’ some of the audio, noticeably dropping the level while not seeming to alter the tone at all. There are no gain adjustments making that happen, it’s entirely tape saturation which is very transparent. (There is no compression, either.)

Softer is the treble softening. Defaults to 0, which is still on but very hi-fi and subtle. You can turn it up to get a more ‘old’ tape machine tone, and like the other controls if you need to finetune the effect by ear, your adjustments will probably be around 0.1 to 0.2 if you mean to retain the full fidelity of the mix.

Fatter is the head bump. Defaults to 0, which is still on, but subtle. It can be cranked up to silly/stupid levels if you like. Again, if you want to emphasize the extra roundness and fullness of tape, you might be tweaking this to 0.1 or 0.2. If you don’t have fantastic subwoofers or monitoring that can handle deep bass, leave this at 0! Boosting it will introduce deep lows very cleanly and you might not hear them unless your monitoring is up to scratch. You will also have to turn down Output if you boost this a lot.

Flutter is the tape flutter. Defaults to 0 which is OFF, see comment on ‘dry/wet’. The most amazingly awesome tape recorders did NOT have loads of flutter, but if you want a little ‘spaciness’ or ‘atmosphere’ you can put in small amounts of this, like 0.1 or so. Go by feel, if you can hear it fluttering it’s kind of too much. If you’re using this, please don’t use Dry/Wet to combine the result with dry: you’ll create a flangey effect and it’ll be more obvious than it should be. By design, Flutter is made so you can increase it until it’s too much, so please remember that realistic levels are more like 0.1: too subtle to immediately hear. Go by feel, or pretend you have a really terrific tape machine and leave it off entirely, set Flutter to 0. (For instance, anyone who’s mastering and intentionally adds flutter ought to think hard about whether that’s really helping.)

It’s yours, now, because the Patreon I started last year has been working. If it hadn’t, I wouldn’t have got to this stage. There’s more to come, and the more people who get involved with the Patreon, the more I can do. ToTape5 is free AU and Mac/PC VST because of the people who’ve got involved and given as little as $1 a month ($12 a year, obviously), and because of the people who gave a lot more (we wouldn’t be at this stage without both kinds).

Let ToTape5 be one of many thank-yous I sincerely offer, for staying with me on this journey. As you can see in the video, there’s a lot more in store for us all! Also, a side note because it seems necessary: public opinion is awesome, and talking about Airwindows usually helps me (which in turn helps you, because I do more). But if you have to crow in post after post about how something I did that’s free TOTALLY wipes the floor with some other company’s product that’s very expensive… even or especially if it’s true… PLEASE take it to my own threads and stick to just mentioning that I also have a product that can be auditioned, if you have to mention it in other people’s threads at all.

I understand people get excited, and yeah I’ve devoted decades of my life to being able to do just that: make the best sounding stuff, openly and for free. I realize that’s good news. You just have to be cool about it, especially when I manage to hit one out of the park and it’s free and will end up being open source. We are doing something awesome, and knocking other people’s work is not part of what I want to do with my time. I’d rather celebrate the other folks out there whom I think are doing wonderful things :)


TL;DW: Optimized Airwindows echo with a twist!


Here’s a nice little addition to the Purest line of Airwindows plugins (minimal, stripped down, extremely deep and rich tone in simple and uncompromised ways).

PurestEcho gives you four echoes, sample-averaged to deliver extremely precise timing, each with its own tap. That means you can use it as a delay line and set up discrete echoes which then stop completely: no feedback, only a series of trailing echoes which then get out of the way and don’t mud up your mix. Or you can use it for just a single slapback (use the last, for the longest delay time). Or, you can set up odd effects like increasing volume slapbacks, or use of only certain taps.

Or, you can get a tone that’s part of the 90s: turn all the delay taps on full and then set the delay time really short. You’ll find there’s a tightly controlled pipe-like honk that emphasizes a musical tone… sort of a Dalek-like robot-like thing… and you can play this using the slider. Note: this slider is NOT smoothed, because it’s smashing the buffer anyway, but more importantly if you’re programming in a bassline using this effect you’d need it to abruptly switch frequencies. So think of it as something you’d play via control automation, not so much through live entry on the slider.

Between that and the ability to throw a big rich echo that fakes ‘feedback’ but then gets right out of the way, I think PurestEcho will find its way into peoples’ workflows. I hope you like it :)

My work’s paid for via Patreon, which is going nicely: if I reach the $700 mark, which could happen even this month, in upcoming months I’ll not only release the next ‘greatest hit’ (ToTape is up next!), but I’ll also pick one from the bottom of the list that’s less (in total sales) than what the Patreon is at. By definition that immediately makes plugins like StarChild, Golem, PurestWarm, and PocketVerbs possible, plus some favorites of my own like ElectroHat. (there’s another Patreon goal where I’m still releasing stuff from the bottom of the list, but it’s YOU guys picking it :) at that point, Aura and OneCornerClip will be within reach…)

I’ll get to work on the latest ToTape, and if all goes well I will have another little nifty plug next week while I work on ToTape. Thank you for being there for me! :)

BussColors 4

TL;DW: The Airwindows console emulations, now working up to 192K correctly.


I’m very pleased to bring you the latest version of BussColors :)

This plugin’s a pretty huge deal: it’s been around since before console emulations were a thing, and I’ve been steadily working on it year after year. There’s not been much to do: my original algorithms, once I moved past the earliest incarnation as the ‘Character’ plugins, were so solid that it left little to do. BussColors has sold $22,445 of plugins over the years, as Audio Units alone, in spite of the fact that it has always been a 44.1K plug (due to being based on a convolution model).

The story there is, a guy at NoiseVault always wanted someone to make a plugin which used his sets of hardware convolution kernels, which he’d done at all different levels. Sort of the Nebula thing (Giancarlo has been a great help when I was getting the VST thing going, check out Nebula)

I’m not that. I’m Chris from Airwindows… so I set out to make my own version of this sort of thing, with hardcoded algorithms generated on-the-fly, as raw and close to the metal as I could get it. And I got some pretty respectable CPU efficiency with all of the tone quality I wanted, limited to 44.1K.


Try it. BussColors4 is the newest version of BussColors, and it works at any sample rate and gets you the same sound. Better, in fact: I like what it does a lot better at 96K and 192K. It also doesn’t greatly expand processing and CPU hit at higher sample rates. I think this one’s a real highlight of the Airwindows arsenal. It would definitely be worth your $50, like its predecessors (well, I always did give existing BussColors users free updates for life, I mean for new buyers). Feel free to shoot it out against the most expensive and/or CPU-hungry options and I think it will clobber all comers.

And since it’s a Patreon supported plugin, it is AU and Mac/PC VST, and it is free. Now, if you LIKE me bringing the industry tools like this to use, you might find it in your best interest to throw me a buck a month using the Patreon so I continue to make and upgrade these plugins. BussColors didn’t used to be ‘all sample rates’, until I worked out how to do it properly, and now it is. I think if you look at the stuff I’ve done, and the stuff I’m preparing to do, you’ll see the point of supporting the Patreon.

It’s a long video. Feel free to just download and start using the plugin, and I hope you like it. :)

Iron Oxide Classic

TL;DW: Old school tape emulation, extra pure and free of grunge.

Iron Oxide Classic

As promised, here is the 2017-ized version of the pure, sweet, original Iron Oxide. No more grit or tape flutter or noise!

It’s funny how this works. If you’re a commercial developer, and you release a plugin that’s real popular, one thing that happens is people begin asking for more. More features, more variations, this and that and the other. The flutter in Iron Oxide 5 came about that way: it migrated over from ToTape (which is also coming to free VST).

Every new thing added is something lost. But since I’m no longer doing strictly commercial development (it’s steadily all becoming free, backed by my Patreon which allows all this to happen) I can do things like confuse the ‘market’ and release both the feature-full Iron Oxide 5, and the stripped-down Iron Oxide Classic. This one is just like the original: input trim, ips control, and output trim. Better yet, it has the pure unsullied tone of the very first Iron Oxide, only brought up to date so it noise shapes to the 32 bit buss etc.

Even if you liked the grunge factor of the very adjustable Iron Oxide 5 (more controls may be added but bear in mind I have a commitment to release plugins like BussColors, not just keep revising Iron Oxide!) you might want to check this out. And if later versions of Iron Oxide wandered away from what works for you, for instance if you’re making electronic music and needed much cleaner handling of synthetic tones… this is your lucky day!

Hope you like Iron Oxide Classic. It is, truly, one of the Airwindows classics, now for free VST and brought up to date. :)


TL;DW: An unusual edge-maker.


This plugin is a weird little science experiment. I’ve got Iron Oxide Classic coming, but I still have to make a video for it and get it ready (and do the other offshoot TapeDust) and this one was ready to go, so here it is :)

Bite puts on a sort of midrange edge. At high sample rates it’ll be more of a trebly edge. It’s no specific frequency, so much as it’s just a harshening factor: you can also use it inversely, to take out midrange edge. It runs a couple samples of latency: on VST that works as a couple samples of delay. Again: an experiment, a science project.

I’ve got some changes (new things you can get) in my Patreon. There’s a new, easier goal to reach: if we get to $700 a month, I will begin releasing a plugin a month from the bottom part of the list: the ones that are on the tail end, scheduled for a loooonnnnggg time from now. That’s in addition to ‘in order of popularity’, which I’m still doing. The ones from the bottom are my pick: the only thing is, I will pick only ones whose lifetime sales are less than what my Patreon is at. As it gets higher, it opens up more possibilities, but I already have some I could do. For instance, StarChild, ElectroHat, or PurestWarm.

As before, if I get to $800 I will begin open sourcing one plugin from what I’ve already released (my pick).

If I get to $900, I will make it YOUR pick which ‘tail end of the list’ plugin we get. It’ll be some sort of vote of patrons or something. Same deal: pick one that has less lifetime sales than my Patreon is at. By $900 that includes Aura (a killer!) and Single Ended Triode, and OneCornerClip. There are a few real prizes in there.

And as before, if I get to $1000 on the Patreon, I’ll put out two free plugins from the top of the list, which will make reaching any particular plugin go twice as fast. And so on… I’m just adding new stuff between the other goals so that we can see more of the fancy plugins come out quicker. It seems to help teach people what I’m about :)

Next, Iron Oxide Classic, as soon as I make the video!

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