Air-G Tape
User Manual
Version 1.0
Based on the work of Chris Johnson — Airwindows.
Source code published under open license.
Table of Contents
1 — What is Air-G Tape?2
2 — User Interface3
Reels4
Tape Head — Head Bump / Head Freq4
Flutter / Flt Speed5
EQ — Low / Mid / High5
Tonal Controls6
Gain Staging7
VU Meter7
3 — Special Modes8
4 — Usage Tips & Presets8
5 — Credits & Acknowledgements9
What is Air-G Tape?
Air-G Tape is an analog tape emulation based on the ToTape9 engine by Airwindows. Its purpose is to transform audio the way real tape does: adding density, natural compression, high-end smoothness, and a cohesion that makes tracks, buses, or mixes sound larger and less digital.
The processing includes harmonic saturation, low-end reinforcement (head bump), subtle wow/flutter speed variations, and a three-band equalizer applied post-tape. Two stereo image modes —Crosstalk and Stereo Width— allow adjusting the stereo field independently from the rest of the processing.
The result can be used in an almost invisible way —to add glue and air to a bus— or more pronounced to color drums, bass, guitars, or the full master. The depth of the controls allows you to find the exact point between transparency and character.
Mechanical Controls
1 Reels
The reels are the visual representation of the tape spools. They animate when the tape engine is active, spinning in sync with the processing.
Interaction: clicking on either reel stops the animation and pauses the visual movement of the reels. A second click resumes them. This function does not affect audio processing —it is a visual preference.
Collapsing the panel: a click on the logo (on the head, between the reels) hides the top strip with the reels to save screen space; a second click shows it again. The logo lights up on hover to show it is clickable, and the transition is animated. (This is purely visual: it does not affect the audio.)
Reels — detail
2 Tape Indicator — LED
The small LED located between the reels lights up when the tape engine is active. It remains off when the plugin is in bypass or inactive.
3–5 Tape Head — Head Bump / Head Freq
Head Bump (control ④)
Head Bump models the "punch" of the head on the tape: the way the magnetic head gives the low end more impact and body, rather than leaving it flat or transparent.
- More Head Bump: greater perceived low-end energy, more "glue". The tape feels more cohesive; bass and kick drum are glued into the mix.
- Less Head Bump: the audio becomes flatter, with more controlled low end.
- Interaction with drive: pushing this area enters non-linear behavior faster.
Head Freq (control ⑤)
Determines where in the low end the bump is felt; shifts the impact point toward sub-bass or toward the low-mids.
- Low Head Freq: the bump sits lower (sub-bass / foundation).
- High Head Freq: the bump moves upward (more presence in the low-mids).
Workflow: first set Head Bump to define the amount; then use Head Freq to place that energy exactly where you want it.

Head section
6–7 Flutter / Flt Speed
Flutter (control ⑥)
Flutter introduces the wow/flutter modulation of the transport: small speed variations that make the tape processing less than 100% stable over time. This happens because in a real machine the motor and mechanical system cause the tape to advance slightly irregularly, generating micro-variations of pitch and timing. The flutter combines a slow wow with a faster flutter plus a gentle drift, mirroring how a real tape machine fluctuates at several rates at once.
- It brings life and movement to the audio, removing it from digital rigidity.
- The more Flutter, the more pronounced the variation. Taken to the extreme, it creates creative degradation: the exaggerated instability deliberately sought to add character or effect.
- Works best once you have Input/Clip Level set to the desired point.
Flt Speed — Flutter Speed (control ⑦)
Adjusts the pace of the wow/flutter: controls how quickly the modulation moves the transport. Low values = slow, expressive wow; high values = fast, vibrant flutter.
Flutter section
Special Modes
Crosstalk Mode (orange LED)
Analog cohesion, tape character, better mono compatibility. See control ⑫ section for full description.
Stereo Width Mode (green LED)
Advanced stereo widening with low-end control in mono. See control ⑫ section for full description.
ST/CT button: toggles between Crosstalk and Stereo Width with each click.
Presets
Button 16 opens the factory presets menu. Air-G Tape includes 48 presets organized in categories:
Mix & Master
- Airwindows — ToTape9 base configuration; neutral starting point.
- Just Tape Glue — minimal coloration, maximum glue. For buses.
- Subtle Bus Glue — nearly invisible glue, no coloration. For master.
- Clean and Open — subtle character with wide stereo image.
- Sweet Spot — balance between character and transparency.
- Modern — controlled saturation with flat response.
- Chrome — chrome tape type: more brightness, less body.
- Vintage — vintage tape with soft compression and low-end body.
- Warm — emphasis on warmth and density.
- Old Cassette — strong coloration in analog cassette style.
- Broken Tape — exaggerated flutter and intentional degradation.
- Lo-Fi Push — high drive, flutter, dark tone. Lo-fi character.
By Instrument
- Drums — Vintage Punch, Modern Glue, Modern Tight, Room Feel, Hard Hit
- Electric Guitar — Thick Tube, Wide Chorus, Crunch Vintage, Lead Bite, Clean Shimmer, Tape Chorus
- Acoustic Guitar — Natural Room, Gentle Spread, Warm Intimate, Open Stage, Vintage Folk
- Bass — Tight Note, Sub Glue, Vintage Round, Aggressive Drive, Warm Upright
- Keys — Soft Pad Tape, Cinematic Spread, Bright Sustain, Rhodes Warm, Vintage EP
- Pads — Wide Wash, Dream Glue, Vintage Nebula, Ethereal Drift, Dark Ambient
- Vocals — Clean Air, Bus Warm, Presence (vocal bus) · Lo-Fi Tape, Phantom (FX)
Presets that use Crosstalk or Stereo Width activate the mode automatically when selected. Current settings are saved with the DAW session (auto-recall).
Usage Tips
Recommended Workflow
- Set Input Gain to achieve the desired level on the VU Meter.
- Use Clip Level to add more or less saturation.
- Experiment with Tape Bias and Tape Shape to find the ideal character.
- Activate Crosstalk for more vintage cohesion.
- Activate Stereo Width for a wider stereo image.
- Adjust Volume to match the perceived level for A/B comparison.
Typical Use Cases
- Subtle use (glue): low Input Gain, Clip Level at 50%, moderate Head Bump. Ideal for buses and master.
- Aggressive coloring: high Input Gain, low Clip Level, Tape Bias toward 0. Ideal for drums and synthesizers.
- Vintage character: Flutter active, high Dobly, Crosstalk activated.
- Low-end control: Head Bump at 60-70%, Head Freq according to the material type.
Visual Indicators — Quick Reference
- LED between reels: tape engine active.
- Click on the reels: pauses/resumes the animation (no effect on audio).
- Click the logo: collapses / expands the reels panel (saves screen space).
- Red LED above Volume: real clip at the output.
- VU red zone: elevated harmonic character — does not imply clipping.
Credits & Acknowledgements
The sonic core of this project is inspired by the work of Chris Johnson of Airwindows, with components drawn from his public code. The saturation and tape emulation engine of Air-G Tape is based on ToTape9, which I consider one of the best tape emulators available. I went a step further trying to make it just a little better.
A user interface was added that, in addition to incorporating useful features (3-band EQ based on SmoothEQ3, Crosstalk, advanced Stereo Width, VU meter), aims to make the experience more pleasant and visual. The result is a sonic behavior very close to the code it is based on, but with extra tools to shape and work the audio with more intuitive visual elements.
All of this with the commitment to maintaining the simple, lightweight, and free philosophy that runs through all of Chris's work.
Airwindows Components Used
- ToTape9 — tape emulation core (saturation, head bump, flutter, wow).
- SmoothEQ3 — low CPU usage 3-band equalizer.
Special Thanks
To Juani and Tomi for their ever-present collaboration. Thank you!
* This project draws its sonic foundation and ideas from Airwindows. Thanks to Chris Johnson of Airwindows for his work and for making his code public.
MIT License — Airwindows
Copyright (c) 2018 Chris Johnson
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
VERSION 1.0