Menu Sidebar


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; Like a highpass on the side channel, except it’s a lowpass.


There are some nice things about Patreon-era Airwindows. Not the money: that sucks, though I think I just about have basic survival taken care of as long as I don’t eat much and nothing happens to my car :)

No, the cool thing is this: I can put out tools that have NOTHING to do with a plugin marketplace. If even one person finds the plugin useful, I can put it out. SideDull is kind of like that. I was asked, ‘since Sidepass is great, can we have a lowpass version?’. And I went ‘huhh? why would anyone want to narrow just top end, or center mids and up while not touching lows?’

The answer is of course ‘why not?’ and ‘if you are sure you won’t be doing that, don’t install this plugin’ :)

I don’t need to explain what SideDull does: it’s the same as Sidepass but in reverse, narrowing/mono-ing highs and down. I WOULD like to explain something about its role in a DAW user’s toolkit, though. I’m seeing this increasing churn in the plugin industry, a frenzy of new stuff and new requirements and DRM systems and dongles and such. It’s like a fulltime job to keep up with your recording system. My own pet fear is updating something only to find that I’ve hosed myself and everything’s now broken.

That’s why SideDull, and every other plugin, is built on a time-capsule 10.6.8 system and the VST’s built on a time-capsule isolated-from-the-internet virtual Windows 7. I’m using the simplest possible interfaces (some vendors, like Blue Cat, have taken pains to implement the generic interface super well, and can even skin it attractively) and not touching stuff that causes forced obsolescence, which I think is really bad news for us all.

So, the free AU/VST plugins (and the Kagi AUs before them) can be like your favorite screwdriver: you get to have the best and simplest audio tools that do NOT break. That also means that if you can only afford legacy computers (or just like being frugal and spending your money on Rickenbackers, as I long to do) you aren’t out in the cold… ever. I’m dedicating the rest of my life to putting tools in the hands of kids and dinosaurs alike, and following it up with my open source initiative. And the longer I do live, the more of it I get to do: but if I keel over tomorrow, all the plugs will still work and I will have had a good day and slept with a clear conscience :)

(and if I do croak, somebody mirror it all! pronto! it’s not all on GitHub yet!)

THERE ARE CHANGES to my Patreon. The tape emulations are closer! I’ve scaled all the goals down to make them more reachable. (remember, I’d like it to be through many people rather than just a few, the goal must remain reached for me to continue doing those rewards!) The new ‘start going through the list one a month’ point is now $600, opensourcing is $800, releasing two a month is $1000 etc. This is added to what I’m already doing, not replacing it: I’ll keep doing the plugins I am doing, you just start to get the ‘greatest hits’ too.

Also, if you missed it: when the release schedule stresses me out, sometimes I turn to game programming. I’ve just put out the mostly-final form of one such game thing, the Minecraft server plugin Snowball Madness. There’s a video and everything, and I have a server up and running this peculiarly anarchic Minecraft variant: it’s at (minecraft 1.11), because sometimes you just need to go somewhere and blow things up with infinite TNT. This is something I keep around, so anyone who’d like to join me and my friends in our occasional building-parties is welcome to learn the ropes (or the snowballs) join, and find some nice secluded spot to homestead. I view it as a longterm anarchy server with a twist (or six), and of course if you’d like to support these researches… which I have to do, to keep from burning out on plugins alone… you can simply support my regular Patreon or direct minecraft-oriented Airwindows fans to do that. Nothing more is needed, this is just another thing I do and have always done :)

Snowball Madness

TL:DW; More Airwindows game research, with source code!

SnowballMadness.jar | GitHub repository

To stay fresh with plugins, I code other things, and it’s become part of my open source initiative. In fact I’m starting off the plugin open source thing by setting up my GitHub page with hobby game projects (first Counterpart, and now Snowball Madness). So you can read the Java code of this plugin, and use it as a framework for your own ideas. A lot of the initial work was done by my brother Dan, who also advocates open source code. Read More


TL:DW; Compressor for accentuating beats and pulses.


What is ‘ballistics’ when it comes to audio gear? It’s the way the gear handles dynamics coming in. It’s the swing of a VU meter that can tell you what your music feels like.

Or, since this is Airwindows and we don’t do no steenkin’ meters, ballistics is the way dynamics hit this compressor to produce outrageous groove.

This is also a good reason to keep me around working on stuff… this plugin wouldn’t exist if not for an earlier free VST plug from me, called SurgeTide. That one controls dynamics by altering the rate of change of the rate of change OF the rate of change of the audio. What, you may ask, would happen if you did that? I’ll tell you: firstly, there is no smoother compressor. It’s utterly, totally fluid and artifact-less, organic to the Nth degree. But, it doesn’t sound like it’s doing anything until suddenly it kicks in and starts making the dynamics swing up wildly to boost every beat. Incredibly hard to control. You really can get a sense of ‘huge surges of the musical tide’ emphasizing the deepest rhythms, but it’s a bear to set up!

And since I’m still out there working on stuff thanks to my Patreon, now there’s a whole new version, so different it counts as a separate compressor: Surge.

Here’s the thing. Compressors are as unique as, say, guitar overdrives. You can search for the magic one, but there can be all different sorts of ‘right one’, with hugely different characters to ’em. I made Pyewacket as a free VST. It delivers a super-articulate attack transient and leans out the sound rather than simply turning it down, and gives a ‘British Classic Rock’ vibe without any silly adding of faux-analog mud: that one clamps down on the body of sounds while leaving tons of intensity and headroom to the tone. Its ‘ballistics’ are very simple and it’s more about delivering a certain kind of attack, and making stuff more even and consistent.

Surge isn’t anything like that. It’s SurgeTide, but easier to control: just bring it up until it starts compressing enough, and don’t go too far to where it inverts the dynamics. You can hear it easily, unlike SurgeTide. But it still retains most of the uncanny fluid organic quality SurgeTide has, and most importantly, it has the ballistics. That means that if you put a pumping, rhythmic mix through it… it will accentuate the beats in a very aggressive way that’s not like anything you’ve heard before. The attacks pop way out, including the deepest bass pulses: this is yet another way to handle compressed bassy mixes and transform them into something punchier. And unlike SurgeTide, it’s very controllable.

You might want to push it hard enough that the dynamics jump way out. You might want to use it as ‘glue’ and hit it only very gently, and take advantage of that extreme fluid openness (a result of the way its control is so abstracted: again, it alters the rate of change of the rate of change OF the rate of change). The one thing it won’t do at all is limiter-like behavior, it’s way too funky for that! So anywhere you need to use a compressor that is just ultimately funky, bouncy, squishy… try Surge. It might be right up your alley.

THERE ARE CHANGES to my Patreon. The tape emulations are closer! I’ve scaled all the goals down to make them more reachable. (remember, I’d like it to be through many people rather than just a few, the goal must remain reached for me to continue doing those rewards!)

The new ‘start going through the list one a month’ is now $600, opensourcing is $800, releasing two a month is $1000 etc. This is added to what I’m already doing, not replacing it: I’ll keep doing the plugins I am doing, you just start to get the ‘greatest hits’ too. Looking forward to entering that phase! (and once those ARE out, I’m free to develop new versions like I’ve done in following SurgeTide with the way more useful Surge).

DC Voltage

TL:DW; Literally control voltages for digital workstations, because why not?


This is exactly what it says on the tin. Do NOT just put this in a mix and crank it up to see what it’ll do. If your whole system is DC-coupled you will blow your woofers, just like that, after a big ‘whump’. I will not take responsibility for damage caused by misusing unusual tools.

What SHOULD you do? Here are some ideas.

There is no DC offset filter nearly as good as applying an opposite offset. Use metering, perhaps option/alt-dragging on the slider if your DAW permits it, to cancel out a DC offset without any sonic penalty at all. This is called a ‘DC servo’, but digitally. If you can get it perfect and then bounce files so you can work with a center corrected section (so you don’t have to get a pop from turning it on or off) this would be the highest quality way to get rid of a FIXED DC offset without altering any of the bass at all. It’ll retain right down to 0.001 hz or whatever, and only kill what is totally unvarying DC.

If you have a converter that’s DC coupled, and analog modular synthesizers, you can use this to create and modulate control voltages. Use it as a voltage source and then mix stuff together using DAW routing much like you use patchcords on your synthesizers, and be careful not to route control voltages to your monitors! I know there are people who’ve done odd things to get DC voltages inside their DAWs. Now it’s a lot simpler :)

This plugin may not be any use to you, and don’t play with it if you don’t know what it is. If it is useful to you, you already know exactly what you’ll do with it, so go right ahead, now you’ve got DAW control voltages out of a simple plugin.

THERE ARE CHANGES to my Patreon. The tape emulations are closer! I’ve scaled all the goals down to make them more reachable. (remember, I’d like it to be through many people rather than just a few, the goal must remain reached for me to continue doing those rewards!)

The new ‘start going through the list one a month’ is now $600, opensourcing is $800, releasing two a month is $1000 etc. This is added to what I’m already doing, not replacing it: I’ll keep doing the plugins I am doing, you just start to get the ‘greatest hits’ too. Looking forward to entering that phase! I feel that more people will recognize the worth of my Patreon if those plugins begin coming out. They are pretty amazing (and once they ARE out, I’m free to develop new versions, opening up my researches even wider).


TL:DW; Mastering highpass to set by ear only!


This is specially by request from Gregg of Hermetech Mastering: it’s my try at a specific plugin he wanted. He wasn’t able to find a fantastic-sounding highpass with JUST a frequency control and slope, no bling, no other stuff, as small as possible.

This is of course right up my alley :)

All the more when he responded warmly to my idea of having both the cutoff and slope have NO LABELING to guide you: just 0-1 sliders. You have to listen. That’s the whole point, and I delighted in taking it that one stage further.

Two stages further, because I worked out how to make the slope control continuous. It uses up to six poles (staggered, an idea that Gregg and I independently came up with: it’s present in my ToVinyl2 and ToVinyl3) but as each pole is added it gets its own little dry/wet internally, so you can have two and a half or four and a third poles. Smooth continuous adjustment of how many poles (and how steep the slope), much like my bit-crusher has continuous sample rate crush and bit depth crush.

Three stages since it uses Airwindows interleaved IIR filtering for the very first stage to start off at a slope even shallower than one pole of IIR: sort of ‘half a pole of filtering’ to start off.

The controls are set up to give useful results around the middle of their travel. I’m not sure exactly how many poles that is, or what frequency: use your ears, says me and Gregg (for whom I made this). I do know that depending on how you set it, the transparent cutting of extreme low frequencies WILL give rise to higher peaks, so either gain stage it or use limiting or clipping. This plugin is not a loudenator. It’s a tone shaper, for retaining every possible bit of tonality while reshaping the extreme lows to trim the lowest frequencies: it’s sound balancing, not ‘make louder-ing’.

This work is made possible through my Patreon, without which I wouldn’t be able to do stuff like this. The more it expands, the larger projects I can tackle. Do bear in mind that I’d rather have 20 people easily paying $1 a month, than one person trying to pay $25 and then having to bail right away: do what is comfortable for you.

Hope you like Hermepass! :)

Ed Is Dim

TL:DW; Mid/side conversion utility plugins.


It’s always nice to expand one’s horizons! You don’t have to run the latest Logic to be able to use any plugin in mid/side mode… though you might need to do a little fiddling with settings.

EdIsDim comes in two plugs: first use MidSide to convert your stereo track into mid/side (on left and right channels). Then apply your processing (there’s a control with which you can balance the mid/side balance, which also means you can gain stage the M/S content into your plugin), then, go into EdIsDim (read it backwards) to convert back to stereo. The same control is present, and can reverse the gain staging you applied. Read More


TL:DW; An Airwindows video game, with source code!

CounterpartWin32 | CounterpartWin64
CounterpartMac32 | CounterpartMac64
CounterpartLinux32 | CounterpartLinux64

When I’m not coding plugins, sometimes I make video games! This one was my first Unity game, done over the last couple years. Read More


TL:DW; Wobbly and weird!


As useful as utility plugins are, sometimes you just have to do something wobbly and weird. Here’s Melt!

To explain what it’s doing will be a little tricky. You can just download it and play with it, but if you want to know what’s under the hood, here goes.

Suppose you have a delay buffer. You can read ‘echoes’ out of the delay buffer. If you like, you can move them around, which changes their pitch.

What if you started reading at one point, and stopped at another? You’d get a delayed ‘moving average’, a series of samples combined. It would be duller, rolled-off.

If you took that section and moved IT, then you’d have a rolled-off, darker delay tap that changed pitch.

Now, what if you took all the start points and all the end points, and made them all wobble and sway around independently, so that the shifting delay taps also changed in tone color and volume even while they pitch-shifted around?

Well, that’s Melt. It’s pretty freaky, when cranked way up. You can run a long extended delay, causing it to resemble a strange retro ambience effect, or you can tighten it right up so that you have more of a chorusy thing. It probably should always have a bunch of pitch shift depth, otherwise it’s a mite boring. You can include dry, or just crank up the wobbly weirdness: should be nice on pads and things, or anything that has to be more dark and diffuse and unpredictable.

Speaking of unpredictable, I’d be working faster but my house got run over by a car, and my Mom recently went into the hospital with a medical emergency (back out and no worse for wear, which is more than can be said for my porch). I am going to try to keep up the pace, but it’s not been a great month for Chris from Airwindows, and I am hoping things get a little more manageable. The driver’s insurance company is going to pay for the porch but I may have to sic my house-insurance company on them, and I do have to handle all the hiring of contractors and all that, personally.

Airwindows is supported by my Patreon, which is not nearly enough to deal with any of these things going on. But I am still plugging away, and hope to soon put out the video game (now with Airwindows sound!) that I was working on much of last year, along with its code, including audio code and many other useful resources. I’m hoping that, just as I make tools for mixers, I can also be of service making tools (and experiments) for game-makers, and this might help support the Patreon.

Guitar Full Wave Rectification

I was just rebuilding an SG copy I own (Samick guitar, real bridge/tailpiece/pickups except the pickup baseplates were so worn out I had to put the Gibson pickups on Ibanez baseplates) when I discovered something. The Dan Armstrong ‘Green Ringer’ (or even a reissue, like the one I have) is far more significant to Frank Zappa’s solo tone than I’d imagined, with instances built into his famous SG and also a Strat (I think I hear this effect on ‘Watermelon In Easter Hay’), and here’s the deal…

It’s way more adaptable to any single-note-lead playing guitarist than you’d think. Or even some double-stops and chords. And it will not automatically make you sound like Frank… but it will mutate YOUR sound into a sort of hypercharged, octave-boosted version of your sound, with many similar effects. And, at least with my Samick SG and reissue Green Ringer, I can build it into the SG without routing or removing controls, and I have done. (see full post for the pictures) Read More


TL:DW; Design your own tone-shaped TPDF.


I explained how DoublePaul was made: taking a TPDF highpass dither, and including additional nearby samples to cause the tone of the noise to be more high-pitched.

Wouldn’t be fair if I didn’t give you a chance to play with it yourself :)

To use BuildATPDF the way I used it, set the middle sliders to -1 and +1. Then adjust the other sliders until you’ve tailored the sound of the noise in a way you like. With the other sliders at 0, you have PaulDither. If the surrounding sliders ‘oscillate’ (going minus, plus, minus, plus) you have more of what DoublePaul is. Tailor the highpass in ways gentle or obvious, or even darken the highpass while leaving its dither functionality intact! It’s the combination of a -1 and +1 tap that gives you highpassed TPDF. (This won’t work with +1 and +1, because it’s the same random noise passing through the plugin: it needs to play a positive node against a negative node)

Or, you can set up the -1 and +1 taps, and then just play with the sliders to see what it sounds like!

Airwindows is supported by my Patreon, and I’ve produced 44 plugins as free VST including this one. Amazingly, not all of them are dithers :)

Newer Posts
Older Posts


handsewn bespoke digital audio

Kinds Of Things