Run the signed package
Open the universal DMG and run Install FAT BOY.pkg. It installs AU, VST3, the standalone application and this guide. Apple Silicon and Intel use the same package.
EnginesClassic / Modern
ProcessingMono / Stereo
Quality1x to 8x
FormatsAU / VST3 / App
00 / Installation
Install once.
Close audio hosts before installing. FAT BOY ships with a conventional installer and complete uninstall path on both supported platforms.
Run the x64 setup
Launch the Windows installer as an administrator. It places VST3 in the shared system folder and the standalone application under Everworks.
Rescan once
Reopen the DAW and refresh its plugin cache if FAT BOY does not appear immediately. Logic uses AU; most other supported hosts can use VST3.
01 / Start here
Three moves.
FAT BOY is level-dependent. Feed it deliberately, compare at matched loudness, and decide whether you need the exact Classic color or the expanded Modern engine.
Choose the engine
Use Classic for the familiar reference response. Use Modern when you need transient, spectrum, low-end and character control.
Set Drive and Amount
Raise Input/Drive until the transfer reacts, then use Effect/Amount to blend the nonlinear result with the source.
Match the output
Use Output or Modern Auto Gain before judging. Louder nearly always sounds better for a moment; matched level tells the truth.
02 / Architecture
Two engines.
The modes are separate signal paths. Classic is preserved for repeatable color and parity. Modern is an Everworks design with stronger control and overload-safe transfer behavior.
Classic
The authorized reference behavior: original transfer, overload foldback, Split path, clipping option and minimum/maximum-phase oversampling.
- Use for familiar mastering density and color.
- Maximum-phase modes carry substantial latency.
- The In control bypasses the nonlinear stage inside the engine.
Modern
A monotonic saturator with independent transient contour, harmonic focus, low-band restoration, odd/even character and stereo-aware control.
- Use when Classic is too fixed or too aggressive.
- Choose Live, Standard or Master quality.
- Amount must be above 0% for the advanced shaping controls to act.
03 / Classic
Exact color.
Classic keeps the shorter interface and the reference control set. Start at 1x or 2x Min Phase, then move to a higher quality only when the source benefits from it.
Input
Drives the transfer before processing. More Input means more density and more overload interaction.
Effect
Blends the shaped signal with the aligned dry signal. At 0% the nonlinear contribution is absent.
Curve
Changes the transfer contour. Positive values feel denser and more forward; negative values are softer and more open.
Output
Post-process attenuation for level matching and headroom. It does not alter how hard the input hits the engine.
Clip / Split / In
Clip enables the reference output clip. Split selects the internal split path. In enables or bypasses Classic shaping.
OS / Phase
Select 1x, 2x, 4x or 8x. Min Phase is the practical real-time path; Max Phase prioritizes phase symmetry and adds latency.
04 / Modern
Shape the weight.
Modern expands the interface. Its four primary controls establish the nonlinear sound; the lower row decides how that sound moves, where it lives and how safely it leaves the plugin.
Drive
Sets the level into the saturator. Use it as the main density control before Amount and Shape.
Amount
Controls the wet nonlinear path. Punch, Focus, Bass Preserve and Character require Amount above 0%.
Shape
Moves the base monotonic transfer from softer to firmer curvature without entering Classic foldback.
Punch
Protects transients from excessive saturation and adds a transient contour of up to approximately 5.6 dB.
Focus
A wide harmonic tilt around 1.8 kHz. Turn left for body and lower harmonics; turn right for presence and upper harmonics.
Bass Preserve
Restores the unprocessed low band below approximately 190 Hz, keeping kick and bass fundamentals stable under drive.
Character
Morphs from odd symmetry toward a bounded asymmetric, even-rich transfer. DC is removed continuously.
Stereo Link
Links transient and Auto Gain decisions between channels. Use 100% to keep stereo movement stable; reduce for dual-mono behavior.
Auto Gain / Safe / Delta
Auto Gain matches long-term pre-drive power. Safe bounds peaks. Delta outputs the removed or added difference for diagnosis.
Drive
→
Shape + Character
→
Focus + Punch + Bass
→
Auto Gain + Safe + Output
05 / Workflows
Useful starting points.
These are starting ranges, not presets. Move Drive first, then match output. Use Delta briefly to understand the intervention and turn it off before final listening.
Mix bus density
Use Classic for a known color or Modern with modest Drive. Keep transients intact and compare at matched loudness.
Amount 20-45%Punch 15-35%Focus -10 to +15Auto Gain ON
Drums and percussion
Raise Punch until attacks recover, then move Focus right only if cymbal harmonics remain controlled.
Amount 35-70%Punch 40-80%Focus 0 to +30Safe ON
Bass and low-end buses
Use Bass Preserve to stop saturation from changing the weight of the fundamental while Character adds upper translation.
Bass 60-100%Character 15-45%Focus -30 to 0Link 100%
Parallel harmonic layer
Push Drive and Character harder, use Delta to inspect the added material, then return to normal output and blend with Amount.
Drive +6 to +12 dBAmount 15-40%Character 40-80%Master 8x
06 / Quality
Spend latency deliberately.
FAT BOY reports the selected latency to the host. Changing engine, oversampling, phase or quality updates host compensation automatically.
| Engine | Mode | 48 kHz latency | Recommended use |
|---|---|---|---|
| Classic | 1x | 0 samples | Tracking, auditioning, minimum CPU |
| Classic | 2x / 4x / 8x Min | 49 / 56 / 60 samples | Mixing and normal mastering |
| Classic | 2x / 4x / 8x Max | 3388 / 3431 / 3465 samples | Offline or latency-tolerant mastering |
| Modern | Live / 2x | Reported by host | Lowest-latency Modern monitoring |
| Modern | Standard / 4x | 61 samples | Default mix and mastering path |
| Modern | Master / 8x | Reported by host | Final render and exposed high-frequency material |
Phase mode is not a quality badge.
Classic Max Phase is useful when its phase behavior solves a specific problem. It is not automatically better, and its roughly 70 ms latency at 48 kHz makes it unsuitable for live monitoring.
07 / Evaluation
Listen without being fooled.
Nonlinear processors can gain level quickly. FAT BOY gives you Output, Auto Gain and Delta so that density, transient shape and spectrum can be judged separately from loudness.
Match level first
Toggle host bypass after matching integrated loudness. A small peak difference is acceptable; a large average-level difference is not.
Hear the intervention
Delta outputs the processed difference. Use it to find pumping, unwanted low-end movement or excessive high harmonics.
Control the edge
Safe applies oversampled soft peak control plus a final sample bound. It is protection, not a certified true-peak mastering limiter.
08 / Support
Fast answers.
Most apparent faults are caused by a zero wet amount, uncompensated gain, an unsuitable phase mode or a host that has not refreshed its plugin cache.
Punch, Focus, Bass Preserve or Character seem inactive
Confirm that Modern is selected and Amount is above 0%. The advanced controls shape the Modern wet path; with Amount at 0% there is no harmonic path to reshape.
The processed signal is much louder
Enable Modern Auto Gain or reduce Output. Then compare again after the long-term gain matcher has settled.
The plugin reports thousands of latency samples
Classic Max Phase is active. Choose Min Phase or Modern Live/Standard for low-latency work.
The plugin does not appear after installation
Close the DAW, rescan AU/VST3 plugins and reopen the host. On macOS, verify the plugin is in the system Audio Plug-Ins folder.
Stereo image moves under heavy processing
Set Stereo Link to 100%. Lower values deliberately allow each channel to make more independent transient and gain decisions.
Which format should I use?
Use AU in Logic Pro and other AU hosts. Use VST3 in REAPER, Cubase, Nuendo, Studio One, Ableton Live and compatible plugin servers.