Airwindows

UnBox

TL;DW: Unbox is a distortion where only the harmonics that don’t alias are allowed to distort.

While I’m putting out my library of plugins according to plan, sometimes I need to take a detour into new stuff. UnBox is one example.

The idea’s as follows: if you distort stuff digitally, it aliases. This can be seen as harmonics seemingly bouncing off the highest frequency, and going back down again. The idea is that if you have digital saturation or distortion without massive oversampling, you’ll always have aliasing and everything is ruined forever.

That’s not quite true. It depends on the frequency, and the form of distortion… and many of my plugins have gentle enough distortion curves that they throw a limited number of harmonics. If you are only generating harmonics within the range of digital audio’s frequencies, you’re fine and there will be no problem until you feed the system a frequency that’s too high. You’re not automatically feeding superhigh frequencies all the time if you’re working with natural recordings: not all sounds contain that kind of high frequency content.

If you DO have that sort of high frequency content, what then? It occurred to me I could take the difference between dry and distorted, store it in an averaging filter, and average it. This would suppress high frequency content in only the distortion artifacts. (I then learned that I needed to average the signal being fed to the distortion part, which is Spiral again: it got a little complicated)

And I could even highpass the distortion part… and all this is applying only to the distortion part. It’s all handled as a single subtract from the raw signal coming in.

What that means is this: UnBox is a distortion that cuts down the level of the signal, but ONLY the mids. Depending on how it’s set, it will let through more and more of the ‘dry’ highs, unaffected. It’ll also let through a hint of bass for definition. Underneath this layer of clarity, the distorted part can be made pretty distorted, but it’ll stay free of aliasing even up into the high frequencies, because those frequencies aren’t actually getting applied to the distortion, and the distortion output’s also being smoothed after the fact. So you’ve got a texture-thickener, an energy-adder, that retains a very analog quality because all of the overtones stay clear of aliasing WITHOUT oversampling. The raw sound is still a direct pass-through and that’s where the clarity comes from.

Wish me luck: I’m having frantic people leave me messages saying that Steinberg will kill my ability to release VST plugins. If they did, I’d have to go back to AU only I guess, but please torrent and distribute the NewUpdates.zip with my plugin library in case they send the black helicopters. More seriously, I’ve sent in their VST2 licensing form (I think I may have already? They’re just sowing chaos at this point) and I’m building all my stuff on time-capsule computers (or virtual machines) that do not change, so I can continue to do things like support PPC Macs. I am the last person to be bullied away from legacy support and they’ll just have to deal with that fact: if all goes well I’ll have my little VST2 agreement and will be fine.

Also, I do not sell the VST plugins: I’m supported by Patreon which is basically selling ME as a working developer. I do realize that if I’m forced not to include VST support that would be a big challenge, but I’m not going to get forced away from VST support after all the years people were begging for it. I chart my course and Steinberg can just deal with that, and I would be very surprised if I was ordered not to include VST in my open-source efforts. Also, I’m not a large enough business to harass, and I’ve never sold even one VST plugin: my incorporating VST went along with my going Patreon, and there are no DRM features on the plugins so even I can’t shut them off remotely. Everything’s going to be fine, if I can have anything to say about it. Enjoy today’s new plugin, which includes both Windows and Linux VST versions alongside the 64/32/PPC binary Audio Units for Mac.

Date September 9, 2018
Author Chris
Comments 5 Comments

Ditherbox

TL;DW: Ditherbox is a switchable selection of dithers in 16 and 24 bit, plus monitoring tools.

Ditherbox

This one’s fairly simple to explain. It’s (nearly) every Airwindows dither plugin in one box, with a control to select between them.

Well, there’s a bit more: Ditherbox comes with 16 bit versions built in (the individual plugins are based on 24 bit, with the exception of NotJustAnotherCD). So rather than messing around with BitShiftGain (which will still give you any weird bit depth you could wish for) you can output to CD-quality 16 bit directly from Ditherbox. That was kind of waiting for Ditherbox to come out, didn’t want to steal all of its thunder.

Oh, did I say thunder? Ditherbox also comes with monitoring tools: calibrated SlewOnly and SubsOnly playback, where it’s supposed to give you roughly the same levels and dynamics from full bandwidth, SlewOnly and SubsOnly. Might not be exactly the same, but if one of them is wildly different from the full bandwidth you might have a look at the mix.

Lastly, it has a new trick: Silhouette! The idea behind this one is simple: calibrated noise replaces your mix. If you can still hear beats and dynamic behavior, or best of all if your music is kind of recognizable, it’s a good sign! That means your mix is communicating information dynamically. If it’s just a wash, you might want to look at your overcompression or over-limiting, because especially now in the days of replay gain, it’s good to leave the ability to communicate with dynamics and not squish everything too much. It’ll also tell you things about how spikey your compression peaks are, and the dynamic texture of your drum impacts.

This plugin marks the open-sourcing of everything I’ve ever done dither-wise, including the Benford Realness-based Not Just Another Dither (named by the internet!). Seemed sensible, as they are all included in Ditherbox (well… actually the TPDF-based stuff like TapeDither, NodeDither, PaulDither, DoublePaul didn’t get included as they weren’t in the original Ditherbox. I’m kind of exhausted doing this one and VSTing it and opensourcing everything: there was a lot of fussy porting work and barely room to move the slider on the VST: forgive, plz?)

Anyhow, with MOST of the Airwindows dither work represented, hopefully this is fun to fool with. I do still recommend Not Just Another Dither on general principles, as in practical terms it’s the best one. You can still put TapeDither on outputs going to a mix, I’m just saying, it all culminated in NJAD.

This is all supported by Patreon. I am rekt, heading to bed now. Goodnight :)

Date September 2, 2018
Author Chris
Comments 16 Comments

Channel6

TL;DW: The latest Channel uses the Spiral algorithm.

Channel6

I use the plugin Channel to test out my latest code regarding things like how to prevent denormalized numbers, what’s the best noise shaping to return to the floating point buss, and so on. That’s because after a fairly brief debug period (at first, the model-choosing popup wasn’t actually changing anything and you always got SSL behavior) the plugin was established as a totally complete plugin: it always used the same ‘Density’ algorithm for the saturation, it always blended that with dry signal using a drive control that was really a dry/wet control (which gave it its openness at partial settings), and it always used the same slew clipping and simple IIR highpass code each time, which was so simple that it couldn’t be improved.

And it’s always been ‘one’ of my most popular and successful plugins, through all those variations. Once there was a big blind shootout on the most popular plugin forum (back when people did that) and someone put up my stuff against several contenders including the most hyped plugins out there. At the time I was selling plugins for $50 a pop, and I’d hoped someone would pick BussColors and do a comparison against my flagship tone-emulator, and have it clobber its rivals in blind testing.

Instead they picked the latest Channel, and used its settings of ‘API’ and ‘Neve’ and ‘SSL’ (in other words ‘slew clipping and a simple highpass and Density’, no real ’emulation’ just shaping set to calibrated amounts), and that free plugin was the one that clobbered the pricey rivals. And soon blind testing went out of fashion, because such shenanigans get embarrassing I guess :) And I didn’t get any sales out of it as Channel was free, but it was fun to watch.

So will this be…

Channel is back in version 6, and there’s one key change. The distortion algorithm which I thought was unbeatable has now been beaten by Spiral… so now Channel uses Spiral, not Density, for its distortion model! For once this should be a plainly audible change: Spiral’s less fat-sounding than the Density algorithm. (I fixed the bug with the dry/wet control in the video: now dry doesn’t clip)

What won’t change is this: you’d be surprised how little ‘processing’ can give you a great, analog-style sound. Literally all Channel does is apply a very simple IIR highpass, add a distortion that’s very clear and pure-sounding, and do a slew clipping set so high that it will almost never kick in. The highpass isn’t very steep, because it’s just one stage of interleaved IIR filter (a trick I use in a more complicated way in Capacitor). These are subtle, gentle differences… but they’re done with absolutely minimal processing, not tons of processing, and the data integrity is kept pristine through long double math and noise shaping to the floating point buss. In simpler terms: this doesn’t suck your tone like heavy digital processing does, this applies ‘hardware-like’ changes calibrated to measurements of real hardware, and this does it at impressively low CPU compared to other plugins of this type.

And it’s free, always has been. So if you feel the need to behave as if it was $50 for a perpetual license, lifetime support and the source code (I know, a whole $50 for all those things? Shocking) then please pretend you were buying one of my other plugins instead, and go to the Patreon and pledge the amount that equals $50 a year.

Then, in a year, if I’ve made another plugin you like, do it again :)

Date August 26, 2018
Author Chris
Comments 7 Comments

BitGlitter

TL;DW: Hardware-style bit and resolution crusher, like really old sampler.

BitGlitter

Just like last week, when I added a compressor to a big pile of free compressors, this week I’m adding a bitcrusher to a growing pile of free bitcrushers.

Just like last week, there’s a little more to it than that.

I’m updating-in-place DeRez, simply to change the labels on the controls (there’s also a tweak with denormalization code, but that’s because people asked for it to gate to silence at low bit depths and that isn’t actually how you gate a bitcrusher to low bit depths: I demonstrate in the video for BitGlitter). The controls needed to be Rate and Rez, not Freq and Reso, because it’s not a filter and Reso is supposed to stand for Resolution, not Resonance. DeRez is the simpler, purer bit and frequency crusher, and is still the best ‘analog setting’ bitcrusher (because it lets you use floating-point or fractional frequency and bit crushes). It’s a very pure example of those things and you can make it gate with a touch of DC offset from DC Voltage, and it’s even got a touch of grit softening when it frequency crushes to improve its tone.

BitGlitter, however, isn’t DeRez. BitGlitter’s something a lot more sophisticated: a kind of sampler emulator. At every stage it’s designed not for bitcrush alone, but to get the particular tonalities you can get out of primitive old samplers. An earlier attempt intentionally went after the old Akai sound, but currently BitGlitter has no specific model. It’s just there to dial in a kind of punchy grit that will make beats sit well against other elements: the video demonstates this.

Now, I know there are people who get mad when I make plugins like these. They say, ‘stop making the sound worse!’ and I understand what they mean, but sorry, I won’t stop because I know there are elements to certain ‘bad’ sounds that aren’t just ‘bad’ but usefully different. BitGlitter maximizes this as much as I can, and might be the go-to textural element for this sort of thing if generic bitcrushing etc. just never works for you. And then for some people I think it’ll immediately be their best friend, but I don’t need to explain to that crew what this is. For those who aren’t used to ‘crappy old sampler’ magic…

First, BitGlitter’s got gain trim going into a stage of Spiral analog-style saturation. You can overdrive the input effectively. Then, it does a hint of bitcrushing and splits into two separate frequency crushers, each set slightly different. This isn’t ‘accurate’ to any real retro sampler, but it helps broaden the sound. The output of these are blended and given an output gain and a dry/wet in case you need to sneak a little clarity back in there, and a slight averaging blur is added to the blend to further emulate analog circuitry.

The result is a coarser, more opaque sound which still lacks modern digital ‘edge’: you can plainly see on a metering plugin like Voxengo SPAN how the highs are softened. It’s not a digital bright-maker, it’s a texture-changer and impact-maker. Especially if you go for darker regions of the Bit Glitter control, you can use this to add ridiculous amounts of midrange punch in that ‘retro hip-hop’ kind of way. There’s a visceralness and aliveness to the grunge because it’s made by an algorithm to act like analog gear might: you won’t get the same result out of just a pile of typical DAW bitcrush and EQ. BitGlitter will do the extreme damage you might be looking for, but it’ll do it with a personality that contributes instead of detracts.

If you like me doing this sort of thing, and especially if you’re using one or more of my free plugins so much that you’d have bought one if they were being sold at $50 a plugin, you can support my Patreon. I can keep doing this stuff thanks to the Patreon. It’s been kind of rough over the last couple years but I think I’m up to the point where I’m sure I’ll continue to live and do this work: not that I can have health care or anything, but I’m pretty careful and plugins aren’t usually dangerous, so with a bit of luck I’ll be okay. Sometimes I can even go places and do things, if I try and cut down on things like food! Also, existing on a bit over $1000 a month keeps me in touch with the 2018 musician lifestyle :D and the great thing about Patreon is it’s more stable than operating as a commercial business was. For that I thank my patrons <3

Date August 20, 2018
Author Chris
Comments 9 Comments

Chris

UnBox

Ditherbox

Channel6

BitGlitter

handsewn bespoke digital audio

Kinds Of Things

The Last Year

Patreon Promo Club