TrueHear Studio Suite

Binaural Symmetry & Assistive Mastering for Logic Pro

TrueHear Studio Suite & MasterDensity

A lifetime of music took its toll on your ears. Keep making your best records anyway.

The complete Logic Pro mixing and mastering solution built for musicians with real-world hearing loss.

TrueHear Studio Suite & MasterDensity is a suite of Apple-simple Logic Pro Audio Unit plugins and a unified macOS standalone application that translates hearing blind spots, frequency congestion, and inter-bus masking into clear visual diagnostics and one-click Logic Pro fixes.

5 Dedicated Logic Pro AU Plugins (.component) Unified macOS Standalone App 10-Band ISO Audiogram & Tinnitus Sync 6–16 kHz Octave-Down HF Microscope Multi-Bus Clash & Logic Channel EQ Preset Generator Reference Track Target & A/B Matching

📖 Read the Official User Manual & Mixing Guide →

Interactive Suite Simulator Click Scenarios Below

The Studio Problem

Why Standard Analyzers Fail Engineers With Hearing Loss

Almost every working producer, mixer, or musician eventually experiences high-frequency roll-off, a 3–6 kHz noise notch, loudness recruitment, tinnitus masking, or Left/Right ear asymmetry. Standard FFT spectrum analyzers only show raw decibels—they don't protect you from the six real-world studio mixing traps:

1. The Over-Compensation Trap 3–6 kHz Notch / HF Loss

When your ears have a 20 dB dip at 4 kHz or a roll-off above 8 kHz, your instinct is to boost vocal presence, snare snap, or cymbal air until it sounds balanced to you—making the mix brittle, sibilant, or icepick-harsh on flat studio monitors.

✓ Solved By: TrueHear EarProfile & Guard shades your blind-spot zones on the spectrum, flags harsh over-boosts inside your dip, and lets you Preview Fix or export a corrective Logic Channel EQ cut in 1 click.

2. Cochlear Masking & Bus Mud Broadened ERB Filters

Sensorineural hearing loss widens cochlear auditory filters (up to 2.5×–3.5× ERB broadening) and flattens upward masking slopes. Overlapping instruments in the 200–500 Hz mud zone and 1.5–4 kHz vocal zone blur into a mushy wall even when individual tracks are loud.

✓ Solved By: 12-Bus Multi-Bus Inspector & ERB De-Smearing detect exact Bark-band collisions across Vox, Drums, Bass, L/R Guitars, BGV, Keys, and custom buses—generating complimentary Logic EQ & Multipressor presets.

3. Phantom Center Drift L/R Ear Asymmetry

Years of standing next to a hi-hat, crash cymbal, or stage wedge often leave one ear 6–15 dB down relative to the other in the upper midrange. Center-panned lead vocals and snares feel pulled sideways, tempting you to pan or EQ the master bus lopsidedly.

✓ Solved By: Binaural Symmetry Compass measures true acoustic L/R balance objectively across Low, Mid, Presence, and Air bands, paired with SafeMonitor's per-ear asymmetry calibration and headphone crossfeed.

4. Loudness Recruitment & Vanishing Tails Compressed Dynamic Range

An FFT graph shows peak energy, not how damaged outer hair cells compress loudness. Quiet details (−55 to −35 dBFS vocal reverb tails, delay throws, ghost notes) drop completely below your threshold—tempting you to drown the mix in +6 dB of extra reverb—while loud snare hits jump painfully to full loudness.

✓ Solved By: SafeMonitor's NAL-NL2 / CAM2 WDRC Lens and Microscope's Reverb Tail Magnifier gently lift low-level tails into your audible window while tapering smoothly to 0.0 dB on loud transients.

5. Tinnitus Masking & Hidden Sibilance 6–16 kHz Blind Zone

Seeing a spectrum line dance at 7.5 kHz or 12 kHz doesn't tell you whether that energy is silky vocal air, a piercing whistle, or a clipped hi-hat click—especially when a constant 4–8 kHz tinnitus ring masks vocal sibilance right inside that frequency pocket.

✓ Solved By: HF Microscope pitch-shifts 6–16 kHz down 1 or 2 octaves (÷2 / ÷4) into your healthy 1.5–4 kHz midrange (plus Delta Transient Solo & Sub-Bass +1 Oct), paired with Tinnitus Notched-Noise Relief.

6. Late-Session Fatigue & Bounce Accidents 4 kHz TTS & Print Risk

Standard analyzers treat Minute 10 and Hour 4 identically, ignoring the progressive 3–6 kHz Temporary Threshold Shift (TTS) that makes your ears duller late at night ("the 11 PM mix disaster"). Worse, standard monitor EQs ruin your master if you forget to bypass them before bouncing.

✓ Solved By: Session Fatigue (TTS) Dose Tracker monitors cumulative K-weighted exposure (Ear Freshness %) and auto-tightens Guard thresholds late in the session, while BounceGuard™ auto-zeroes monitor EQ during offline bounce.

Deliverables • v2.2.0 Universal macOS .pkg & .dmg Installer

5 Dedicated Logic Pro AU Plugins + Unified Standalone App

All 5 Logic Pro AUv2 plugins and the unified macOS Standalone App install in one click via the macOS Studio Multi-Mac .pkg & .dmg Installer (v2.2.0), share a real-time C++ core library (TrueHearDSP), and synchronize your personal hearing profile instantaneously via ~/Library/Application Support/TrueHearSuite/ear_profile.json and macOS Distributed Notifications.

1. MasterDensity aufx MsDn StTl

Master bus frequency congestion, crest factor, and spectral persistence visualizer.

12 psychoacoustic studio mixing zones (Sub to Air)
Peak-to-RMS Crest Factor & 3.0s Waterfall Heatmap
Mid/Side density split & Low-End Side Mud detector
Click-and-drag Bandpass Solo sweeping
5 Genre Target Curves + Custom Reference Track Target

2. TrueHear EarProfile & Guard aufx ThEp StTl

Interactive Left/Right audiogram calibrator, 10-second AirPods/Mimi importer, and harshness guard.

10-Second AirPods Pro 2 & Mimi Import: Export PDF/JSON on iPhone → AirDrop to Mac → 1-click 📲 Auto-Import (scans ~/Downloads), Drag & Drop, or Cmd + V Paste
10-band ISO audiogram editor + built-in reference tone check
Parametric high-frequency roll-off, 4 kHz notch & Tinnitus marker
Over-Compensation Guard for Bite (2.5–5k), Sibilance (6–8.5k) & Air
Plain-English coaching alerts weighted by your blind spots

3. TrueHear HF Microscope aufx ThMc StTl

High-frequency octave-down pitch translator and L/R phantom center compass.

Isolates 6–16 kHz and shifts it 1 octave down into 3–8 kHz
Sub-11 ms dual-head Hann grain pitch shifter
Lets you clearly hear cymbal fizz, breaths & sibilance
4-Band L/R Symmetry Compass + 1-click L/R Ear Swap check

4. TrueHear SafeMonitor aufx ThSm StTl

Audiological half-gain monitor compensation EQ with automatic offline bounce protection.

Tailored Left & Right ear corrective presence peak & high shelf
Capped at +10.5 dB with soft-clipping ear protection
BounceGuard™: Automatically bypasses during Logic Pro offline bounces so your personal EQ never prints to disk

5. TrueHear Multi-Bus Inspector aufx ThIn StTl

12-bus customizable band clash detector with automatic Logic Pro Aux name pickup & 1-click Auto-Deploy.

Auto Bus Name Pickup: Reads Logic Pro Aux names via kAudioUnitProperty_ContextName / updateTrackProperties (Vox, Drums, Bass, Left/Right Guitar, BGV, Keys + custom band buses like Pedal Steel, Horns, 808 Sub)
1-Second Batch Insert & ⚡ Deploy to All Busses: Shift-click all 12 Auxes in Logic’s Mixer and insert once—zero slot collisions, plus 1-click 12-bus Channel Strip & Preset Kit export
Lock-free POSIX shared-memory audio streaming across all 12 buses (16-bus ready) with zero sidechain routing
Generates & exports native Logic Pro (.pst / .aupreset) & Universal Audio (UAD .fxp) presets

6. TrueHear Suite Standalone App macOS .app + .pkg/.dmg

Unified desktop control center housing all tools, reference track loader, and hardware I/O.

Apple-style segmented navigation across all 5 tools
Load WAV, AIFF, FLAC, MP3, or M4A reference tracks
Loudness-matched Reference A/B auditioning
Ships with the 1-click macOS Studio Multi-Mac .pkg & .dmg Installer (v2.2.0)

Apple-Levels of Simple

How to Get Your AirPods Pro 2 or Mimi Hearing Test Into TrueHear in 10 Seconds

No cables, no iCloud folders, and no 2 GB HealthKit XML archives. If you’ve taken a hearing test on your iPhone with AirPods Pro 2 or the Mimi Hearing Test app, getting your exact Left/Right ear curve into Logic Pro takes three effortless steps:

Step 1: Export on iPhone (2 Taps) iPhone / iPad

Grab the single-page audiogram report right from your phone:

For AirPods Pro 2: Open Apple Health on iPhone → Browse → Hearing → Hearing Test Results → tap Export PDF (or Share).
For Mimi Hearing Test: Open the Mimi app on iPhone → open your test results → tap Share / Export Report (or sync to Apple Health).

Step 2: AirDrop to Your Studio Mac Zero Cables

Beam it straight to your mixing desk:

Tap Share → AirDrop and choose your Studio Mac.
The file lands right in your Mac’s ~/Downloads folder automatically—zero cables, zero iCloud digging, and zero multi-gigabyte XML exports.
Or simply tap Copy on your iPhone to put the report on your Apple Universal Clipboard!

Step 3: 1-Click Auto-Find or Drag & Drop Instant Sync

Inside TrueHear EarProfile (AU plugin or Standalone App), pick whichever feels easiest:

Click 📲 Auto-Import AirPods / Mimi—TrueHear automatically scans ~/Downloads for the file you just AirDropped and loads it in one click!
Drag & Drop the PDF/JSON/CSV/XML straight onto the Audiogram graph, or press Cmd + V (Paste).
Plots Left (Blue) & Right (Coral) 250 Hz–8 kHz thresholds, extrapolates 12 kHz & 16 kHz studio air, detects your 3–6 kHz notch, and syncs all 5 Logic Pro plugins!

Intelligent Workflow

12-Bus Customizable Band Clash Detection, Reference Matching & Logic Pro Presets

12 Customizable Band Buses + Auto-Deploy ContextName + 24-Bark Mesh

In Logic Pro’s Mixer (X), simply Shift-click all 12 Aux buses at once and insert TrueHearInspector on a single slot. Each instance automatically reads its Logic Pro Aux channel strip name via kAudioUnitProperty_ContextName / updateTrackProperties (Vox, Drums, Bass, Left Guitar, Right Guitar, BGV, Keys, or custom band buses like Pedal Steel, Horns, 808 Sub), assigns the matching acoustic role profile, and claims an open slot (01–12) in InterInstanceStemRegistry with zero collisions!

⚡ Deploy to All Busses Header Command: Broadcasts a mesh-wide Auto-Discover & Sync Host Names refresh across all open instances and writes a complete 12-Bus Logic Pro Channel Strip & Preset Kit (01-VOX through 12-PRC) to ~/Music/Audio Music Apps/Plug-In Settings/TrueHearInspector/AutoDeploy-12Bus/ and ~/Music/Audio Music Apps/Channel Strip Settings/Bus/TrueHear 12-Bus Suite/
Calculates 12×12 cross-spectral overlap weighted by your personal blind spots: Risk = Overlap × (1 + 3 × BlindSpotSeverity)
Prioritizes band role hierarchy (Lead Vox > Backing Vox / Snare > Bass > L/R Guitars > Keys > Custom Slots) so it carves the masking instrument instead of boosting into your hearing loss

Native Logic Pro + UAD Plugin Preset Suite .pst / .aupreset + UAD .fxp

Every mix fix recommendation, drum contour, and reference track delta writes native presets directly to disk for Logic Pro’s built-in plugins and your installed Universal Audio (UAD) plugins!

Native Logic Pro (.pst & .aupreset): Writes bit-accurate binary .pst (GAME TSPP) and XML .aupreset files directly to ~/Music/Audio Music Apps/Plug-In Settings/ for Channel EQ (chqe), Linear Phase EQ (lpeq), Compressor (dyna), DeEsser 2 (des2), and Multipressor (mpr4)
Native Universal Audio Binary Presets (.fxp — CcnK / FPCh): LogicPresetWriter::writeUadFxpPreset writes real UAD binary chunk presets directly to /Library/Application Support/Universal Audio/Presets/ for UAD SSL G Bus Compressor (YBAU), UAD API 2500 (UBAU), UAD Empirical Labs Distressor (4CAU), UAD UA 1176LN / Rev A (40AU/V9AU), UAD Pultec EQP-1A (NAAU), UAD Neve 1073 (ZAAU), and UAD SSL E Channel Strip (WBAU)!
Includes an in-plugin 1-click Preview Fix audition toggle and loudness-matched Reference Track delta EQ curves

🥁 Drums First Always (Stage 0): 12-Mic Drum Sub-Mix → Swappable Drum Bus Glue Compressor → Full Band Mix Dual-Scope 12-Slot Mode

Every great record starts with the drums. Before touching guitars, keys, or vocals, switch TrueHear Inspector to 🥁 Drum Kit Mode (Drums First), Shift-click all 12 drum mic tracks inside your Logic Pro Drum Summing Stack, and insert TrueHear Inspector once:

🥁 Deploy to Drums + Flexible Fuzzy Drum Track Name Matcher (matchDrumTrackNameToSlot): Clicking 🥁 Deploy to Drums reads every drum track’s name from Logic Pro (kAudioUnitProperty_ContextName / updateTrackProperties) using a flexible fuzzy/tokenized parser that understands any studio naming style—whether you name tracks "Inner Kick" / "Kick In" / "Kik 1" / "Beta 91", "Outer Kick" / "Kick Out" / "Sub Kick", "Snare Top" / "Snr Top" / "SD 57", "Snare Bottom" / "Snr Bot" / "Snare Wires", "Tom 1" / "Rack 1" / "Hi Tom", "Tom 2" / "Mid Tom", "High Hat" / "Hi-Hat" / "HH", "Stereo Overheads" / "OH L/R", "Floor Tom" / "FT", "Sound City" / "Virtual Room" / "Drum Room", "Crush" / "Smash", or "Drum Bus". Even if two tracks are just named "Kick" and "Kick 2" (or "Snare" and "Snare 2"), collision-aware fallback automatically assigns the first to 01 Inner Kick (03 Snare Top) and the second to 02 Outer Kick (04 Snare Bottom)!
8 Default Core Dry Drum Channels + Virtual Room Aux Inside Drum Sub-Mix (DrumKitSubMix): Defaults to the exact 8 core dry drum channels—01 Inner Kick (KIN) • 02 Outer Kick (KOT) • 03 Snare Top (SNT) • 04 Snare Bottom (SNB) • 05 Tom 1 (TM1) • 06 Tom 2 (TM2) • 07 High Hat (HHT) • 08 Stereo Overheads (OVH)—plus Drum Sub-Mix expansion slots 09–12: 09 Tom 3 / Floor Tom (FLT) • 10 Parallel Crush (CRS) • 11 Virtual Room Aux (VRM — e.g., UAD Sound City Studios) • 12 Master Drum Bus (DRM)! Because the 8 dry drum channels (`01–08`) are phase-locked and EQ’d first, they send a clean, punchy signal into 11 Virtual Room Aux (UAD Sound City Studios) before summing into 12 Master Drum Bus glue!
1-Click 🔄 Recalculate Room Mics Button (recalculateVirtualRoomBus() — Right in the Drum Toolbar): Whenever you drag the virtual room microphones inside UAD Sound City Studios (changing distance from the kit, swapping virtual mic models like C12 ↔ RCA 44 ↔ U47, or adjusting chamber curtains) during drum mixing, clicking 🔄 Recalculate Room Mics flushes only the Virtual Room bus’s spectral/phase buffers—keeping your 8 dry drum mic fixes (`01–08`) 100% locked—and immediately re-measures: (1) Virtual Room ↔ 08 Stereo Overheads / 03 Snare Top Arrival Lag (Δt ms) & Comb-Filtering Risk (warning you if moving the Sound City mics closer created phase cancellation with dry overheads); and (2) Dynamic Abbey Road / Sound City Drum Room EQ Re-Solve—adapts the 180–210 Hz Sub-Boom HPF (protecting dry kick punch), dynamic 260–340 Hz low-mid room-mud carve, 2.2 kHz vocal-pocket carve, and 7.5 kHz Silk LPF (so 08 Stereo Overheads own the cymbal air) to your new virtual mic placement before feeding into 12 Master Drum Bus glue!
Coupled 2-Mic Drum Pair Solvers (01 Inner Kick ↔ 02 Outer Kick & 03 Snare Top ↔ 04 Snare Bottom): Clicking 01 KIN ↔ 02 KOT or 03 SNT ↔ 04 SNB in the matrix (or stepping through Stage 0.1 & Stage 0.2) solves specifically for those two mics as a coupled acoustic pair: (1) Inner Kick ↔ Outer Kick Solver—checks 45–160 Hz phase correlation (r) and acoustic arrival offset (Δt ms) between the inside beater mic and outside resonant head mic, and builds a complementary 2-mic split (Outer Kick owns 52 Hz sub + -3.5 dB @ 85 Hz pocket + 3.5 kHz LPF; Inner Kick gets 55 Hz HPF + +2.5 dB @ 80 Hz punch + 3.8 kHz click); (2) Snare Top ↔ Snare Bottom Solver—catches the #1 studio drum mistake: an un-flipped 04 Snare Bottom mic (r < -0.20 at 195 Hz, where top and bottom diaphragms face opposite directions and cancel out 6 dB of snare body!), gives a 1-click Ø Flip Polarity button, and high-passes Snare Bottom at 180 Hz so Snare Top owns the 195 Hz meat while Snare Bottom owns the 5.2 kHz wire sizzle.
Close-Mic ↔ 08 Stereo Overheads Phase & Comb-Filtering Detector: Continuously measures real-time cross-correlation (r ∈ [-1, +1]) and time-of-flight delay (Δt ms, e.g., Snare Top arrives 3.1 ms [149 samples] before Stereo Overheads) between every close drum mic (Inner/Outer Kick, Snare Top, Tom 1, Tom 2, High Hat) and 08 Stereo Overheads, flagging polarity inversions and comb-filtering cancellations that engineers with high-frequency hearing loss might miss!
Why “Drums First” Saves SNHL Engineers from Cymbal-Bleed & Cardboard Mud (deployDrumKitSubMixChain()): Close drum mics (Snare Top, Toms) contain -10 to -15 dB of hi-hat/cymbal bleed at 3.5–7 kHz. Boosting 4 kHz inside a hearing notch pulls up abrasive cymbal wash; instead, TrueHear deploys split-band DeEsser 2 (6.0–6.8 kHz) on Snare Top & Toms + a 3.5 kHz LPF on Outer Kick + -3.5 dB @ 3.8 kHz blind-spot cuts on Stereo Overheads, while carving 265–340 Hz cardboard shell buildup across all drums so upward cochlear masking doesn’t veil the vocal pocket.
End-of-Chain Master Drum Bus Glue Compressor + Direct UAD .fxp Binary Preset Export (LogicPresetWriter::writeUadFxpPreset): Places Logic’s stock Compressor (Vintage VCA: 4:1, 30 ms Attack, 100 ms Release, SC HPF: 90 Hz, 2.5–3.5 dB GR, Auto Gain: OFF) at the end of the Master Drum Bus (12 DRM) out of the box—and writes real, native Universal Audio binary .fxp (CcnK / FPCh) presets directly into /Library/Application Support/Universal Audio/Presets/ so they show up right inside your UAD plugin toolbar: (1) UAD SSL G Bus Compressor (fxID: YBAU, 11 params) — TrueHear Master Drum Bus Glue (4:1, 30 ms Attack, 100 ms Release, 90 Hz SC HPF); (2) UAD API 2500 (fxID: UBAU, 18 params) — TrueHear Drum Bus Thrust & Punch (3:1–4:1, 30 ms Attack, 0.1s Release, Thrust: Med, Tone: New); (3) UAD Empirical Labs Distressor (fxID: 4CAU, 11 params) — TrueHear Parallel Crush (Slot 10, 6:1, Atk: 4–5 [~30ms], Rel: 2 [~90ms], Detector: HP, Dist 2 even-order tube warmth rounding off harsh 4 kHz cymbal transients); (4) UAD UA 1176LN / Rev A (fxID: 40AU / V9AU, 7/6 params) — TrueHear Fast Snare/Room Catcher (4:1 or All-Buttons, Attack: 1 Slowest, Release: 7 Fastest 50ms, Mix: 35–50%); (5) UAD Pultec EQP-1A (fxID: NAAU, 10 params) — TrueHear Coupled Kick Low-End Trick (60 Hz simultaneous Boost + Atten pocket); and (6) UAD Neve 1073 (fxID: ZAAU, 16 params) & UAD SSL E Channel Strip (fxID: WBAU, 43 params) — Per-channel 01 Inner Kick, 02 Outer Kick, 03 Snare Top, 08 Stereo Overheads, and 11 Virtual Room (Sound City) console contour presets!
“Zero Loudness Deception” Crest-Factor Squash Guard (verifyDrumBusCompressorHealth): Automatically monitors your Drum Bus dynamics (healthy drum window: 10.0–16.5 dB crest factor) and warns you if a swapped UAD/Waves compressor drops Drum Bus Crest Factor below 8.5 dB, preventing fast-attack presets from squashing snare snap and pulling up cymbal wash—before transitioning in 1 click to 🎸 Full Band 12-Bus Mode!

🪄 Optional “Add-a-Bus” Mix Builder Wizard: Kick It Off With One Button (Or Mix Freely!) 100% Optional Button

Free-Mix Mode by Default, Guided Wizard on Demand: Out of the box, TrueHear Inspector runs in standard Free-Mix 12-Bus Matrix Mode—all 12 buses play normally and you can click any clash cell or bus in any order you want. Whenever you want a structured, step-by-step workflow, simply click the 🪄 Start Guided Mix Wizard button in the top bar (and exit back to Free-Mix mode at any time with ✕ Exit Wizard)!

When you kick off the Wizard, TrueHear automatically mutes the rest of the band (progressiveActiveBusMask) so you only hear Step 1: 🥁 Drums (`02 DRM`). Each time you click ✓ Lock & Add Next Bus →, TrueHear automatically unmutes the next bus group into the mix, highlights any new clashes against the buses already playing, lets you click 🔊 Preview Fix, and writes the Logic Pro .pst/.aupreset as you build the record layer by layer:

Step 1 — 🥁 Setup Drums First (8 Dry Drum Mics + 11 Virtual Room Aux [UAD Sound City] → 12 Master Drum Bus Soloed): Dials in per-mic dry drum EQ (`01–08`), 2-mic Kick/Snare phase, cymbal-bleed de-essing (DeEsser 2), your 11 Virtual Room Aux (UAD Sound City Studios) Abbey Road/Sound City room contour (with 1-click 🔄 Recalculate Room Mics whenever you move virtual mics in Sound City), and the end-of-chain Master Drum Bus Glue Compressor before any other instrument is unmuted!
Step 2 — 🎸 Add Bass Bus (02 Drums + 03 Bass | 20–160 Hz): Automatically unmutes 03 Bass into your glued 02 Drums and locks in the 45–120 Hz Kick/Bass pocket using dynamic spectral ducking (Multipressor) so sub energy never triggers upward cochlear masking.
Step 3 — ⚡ Add Left & Right Guitars (+ 04 GTL & 05 GTR | 160–500 Hz): Automatically unmutes stereo guitars on top of Drums + Bass and applies static surgical cuts (Channel EQ) to clear 220–400 Hz cabinet mud so broadened auditory filters (ERB smearing) don’t cloud the mix.
Step 4 — 🎹 Add Keys, Acoustic & Synths (+ 07 KEY, 08 ACG, 09 SYN | 200 Hz–2.5 kHz): Automatically unmutes keys, acoustic guitars, and synth pads into the rhythm bed and separates them from the electric guitars.
Step 5 — 🎤 Add Lead Vocal (+ 01 VOX — Right After Rhythm Beds! | 800 Hz–4.5 kHz): Automatically unmutes 01 Vox on top of the locked rhythm track and carves a dynamic 1.5–4 kHz Multipressor pocket in the Guitars & Keys so the singer owns the phantom center without boosting into your 4 kHz hearing notch.
Step 6 — 🎶 Add Backing Vocals, Horns, Strings & FX Last (+ 06 BGV & 10–12 | 500 Hz–16 kHz): Unmutes 06 BGV and auxiliary ear-candy after the Lead Vocal is sitting on the throne—tucking harmonies neatly behind 01 Vox and polishing 4.5–16 kHz sibilance/air with DeEsser 2! (Includes a 1-click toggle between “Pro Order (Lead Vox Step 5 → BGV/Sweeteners Step 6)” and “Vocals Last”!)
Psychoacoustic Safeguards Built Into Every Step: (1) Cascade Upward-Masking Relief (cascadeReliefDb)—applying low-end/mud cuts in Steps 2–3 automatically recalculates upward cochlear masking into the midrange (1.5–4 kHz) and reduces Step 5 vocal-pocket cuts so you never over-cut; (2) Stage-Aware Dynamic vs. Static Plugin Selection (Multipressor for Kick/Bass & Lead Vox pockets, Channel EQ for low-mid mud, DeEsser 2 for sibilance/air); and (3) “Swiss-Cheese Mix” Prevention Guard (Max 3 Cuts / -9.5 dB Budget Per Bus)—consolidates nearby cuts within <0.35 octaves and caps any bus at 3 EQ cuts max, automatically pivoting any 4th clash to a -1.5 to -2.5 dB broadband fader or stereo pan trim!

Execution Plan & Next-Gen R&D

10-Milestone Engineering & Psychoacoustic R&D Roadmap

Built with a dual-track multi-agent architecture and guided by clinical audiology + music production R&D. Every milestone passes automated headless DSP unit tests, adversarial stress tests, and Apple’s official /usr/bin/auval validator.

Milestone & Release Tier	Scope & Key Deliverables	Verification Gate	Status
M1 (v1.0): Core DSP & Shared Ear Profile	`TrueHearDSP` static library, `SharedEarProfile` wait-free double-buffered IPC sync, `MicroscopeEngine`, `GuardEngine`, `BalanceEngine`, `SafeMonitorEngine` (`BounceGuard™`), and `DensityAnalysisEngine`.	CTest 100% Pass + Stress Tests + `auval`	DONE & VERIFIED
M2 (v1.0): Multi-Bus Inspector & Clash Engine	5-stem assignment, lock-free `InterInstanceStemRegistry` POSIX shared memory mesh, `StemAuditionMatrix`, 24-Bark `MultiBusClashEngine`, and plain-English `FixSuggestionEngine`.	6 Multi-Bus Test Suites + Concurrency Audit	DONE & VERIFIED
M3 (v1.0): Logic Channel EQ Presets & Reference Track	8-band Logic Pro Channel EQ mapping, binary `.pst` & XML `.aupreset` writers, `ReferenceTrackManager` (WAV/AIFF/FLAC/MP3/M4A loader), ITU-R BS.1770-4 K-weighted LUFS matching & reference-delta EQ suggestions.	Bit-Level Preset Verification + Reference DSP Tests	DONE & VERIFIED
M4 (v1.0): 5 AU Plugin Suite & Standalone UI	All 5 dedicated Logic Pro AU targets (`MsDn`, `ThEp`, `ThMc`, `ThSm`, `ThIn`), unified `TrueHearSuiteApp`, zero audio-thread heap allocations, and wait-free UI snapshots.	5/5 `auval -v` Pass + 0 Real-Time Allocations	DONE & VERIFIED
M5 (v1.0): Full E2E Gate & Adversarial Hardening	100% pass across 58 E2E tests, 1.5M-operation concurrency fuzzing, and self-healing IEEE 754 `NaN`/`Inf` filter protection across all processors.	58/58 E2E + 7/7 CTest + 5/5 `auval`	DONE & VERIFIED
M6 (Tier 1 — v1.1): Immediate Precision Polish	All-24-Bark max clash matrix lookup with dynamic skirt rejection, full `SafeMonitor` parameter & dynamic notch frequency wiring, live APVTS ↔ `SharedEarProfile` node-drag sync, dedicated >10.5 kHz Air tap, stereo `L/R` power summation, zero-allocation POD Guard alerts, and 1-click in-place Preview Fix audition.	8/8 CTest + 58/58 E2E + 5/5 `auval` + 0 Heap Allocs	DONE & VERIFIED
M7 (v1.5): Recruitment WDRC, Transient/Tail Microscope, Fatigue Tracker & Multi-Plugin Presets	1. SafeMonitor Dynamic Recruitment Lens (Multiband WDRC): NAL-NL2/CAM2 low-level assist (`-65` to `-35 dBFS`) tapering to `0 dB` at `-12 dBFS` so reverb tails & ghost notes are audible without loud snare/vocal pain. 2. Transient, Reverb Tail & Sub-Bass (+1 Oct) Microscope: Adds `Delta Transient Solo`, `Reverb Tail Magnifier`, and `Sub-Bass +1 Oct (20–80 Hz → 40–160 Hz)`. 3. Intra-Session Ear Fatigue (TTS) Dose Tracker: Tracks cumulative K-weighted session exposure, displays Ear Freshness %, and dynamically tightens `GuardEngine` late in the session. 4. Expanded Logic Pro Presets: Native presets for Logic Compressor, DeEsser 2, Linear Phase EQ, and Multipressor.	16/16 Challenger + 8/8 CTest + 58/58 E2E + 5/5 `auval`	DONE & VERIFIED
M8 (v2.0): Multi-Bus Core, Optional Guided Mix Wizard & AirPods/Mimi Calibration	1. 12-Bus Customizable Band Mesh + 🪄 Optional Progressive “Add-a-Bus” Mix Wizard: Expands `InterInstanceStemRegistry` and `MultiBusClashEngine` to 12 simultaneous stereo buses (`1. Vox` through `7. Keys` + customizable Slots 8–12 & 16-bus shared memory headroom), automatic Logic Pro Aux bus-name pickup (`updateTrackProperties` / `kAudioUnitProperty_ContextName`), 1-click ⚡ Deploy to All Busses, and the 100% optional 🪄 Start Guided Mix Wizard (`Setup Drums → +Add Bass → +Add Guitars → +Add Keys → +Add Lead Vox → +Add BGV/FX`). 2. Apple AirPods Pro 2 (HealthKit) & Mimi Hearing Test Importer + Broadened ERB De-Smearing: 1-click import for Apple AirPods Pro 2 / Apple Health and Mimi Hearing Test exports with `12 kHz & 16 kHz` studio slope extrapolation, plus broadened ERB de-smearing (`-12 → -5.5 dB/Bark`) and cross-stem dynamic spectral ducking.	5/5 Gate + 174/174 Challenger + 10/10 CTest + 5/5 `auval` + 58/58 E2E	DONE & VERIFIED
M9 (v2.1): “Drums First Always” Suite: 8 Dry Drum Mics, Coupled Kick/Snare Solvers, OH Phase Detector, Sound City “Recalculate Room Mics” & Native UAD `.fxp` Exporter	1. 🥁 “Drums First Always” 8-Channel Dry Drum Sub-Mix + Fuzzy Track Name Matcher (`🥁 Deploy to Drums`): Dedicated `DrumKitSubMix` mode defaulting to `01 Inner Kick (KIN)`, `02 Outer Kick (KOT)`, `03 Snare Top (SNT)`, `04 Snare Bottom (SNB)`, `05 Tom 1 (TM1)`, `06 Tom 2 (TM2)`, `07 High Hat (HHT)`, and `08 Stereo Overheads (OVH)` + expansion slots `09–12`. 2. Coupled 2-Mic Kick/Snare Solvers & Close-Mic ↔ Overheads Phase Detector: Dedicated 2-mic acoustic solvers for `Inner Kick ↔ Outer Kick` and `Snare Top ↔ Snare Bottom` (with 1-click `Ø Flip Polarity`), plus real-time cross-correlation (`r`) and arrival-lag (`Δt ms`) comb-filtering detection against `08 Stereo Overheads`. 3. Swappable Master Drum Bus Glue Compressor & UAD Sound City `🔄 Recalculate Room Mics`: End-of-chain Logic `Compressor` + 5-Compressor UAD/Waves Swap Table (`SSL G-Bus`, `API 2500`, `1176`, `Distressor`) with `≥8.5 dB` Crest-Factor Squash Guard, plus `11 Virtual Room Aux (UAD Sound City Studios)` with 1-click `🔄 Recalculate Room Mics` (`recalculateVirtualRoomBus()`) whenever virtual mics move. 4. Native Universal Audio (UAD) `.fxp` Binary Preset Exporter (`LogicPresetWriter::writeUadFxpPreset`): Writes bit-accurate UAD binary chunk presets (`CcnK` / `FPCh`) directly to `/Library/Application Support/Universal Audio/Presets/` for `UAD SSL G Bus Compressor` (`YBAU`), `UAD API 2500` (`UBAU`), `UAD Empirical Labs Distressor` (`4CAU`), `UAD UA 1176LN / Rev A` (`40AU`/`V9AU`), `UAD Pultec EQP-1A` (`NAAU`), `UAD Neve 1073` (`ZAAU`), and `UAD SSL E Channel Strip` (`WBAU`)!	5/5 Gate + 5/5 Empirical M9 (138 Drum Names) + 11/11 CTest + 5/5 `auval` + 58/58 E2E	DONE & VERIFIED
M10 (v2.2): Massive Zero-Slop QA, UI/UX & Clinical/Musical R&D Perfection Gate	Full-suite adversarial DSP stress testing, 16-bus full-ensemble shared-memory concurrency verification, Retina UI/UX pixel audit across all 5 AUv2 plugins and `TrueHearSuiteApp`, clinical audiology & veteran mix-engineering R&D sign-off, and 5/5 Apple `auval -v` certification.	5/5 Gate + 10M-Block ASan/TSan + 11/11 CTest + 5/5 `auval` + 58/58 E2E	DONE & VERIFIED

v1.5: Loudness Recruitment WDRC NAL-NL2 / CAM2

Outer hair-cell loss narrows dynamic range: soft reverb tails at -40 dBFS vanish, yet loud snares at -8 dBFS hit normal/painful loudness. Linear EQ over-boosts loud peaks; our multiband WDRC lens lifts quiet detail while tapering to 0 dB at peak levels.

v1.5: Transient, Tail & Fatigue Lenses TFS & TTS Guard

Counteracts hidden hearing loss (cochlear synaptopathy) and “4 PM Mix Syndrome” with Delta Transient Solo, Reverb Tail Upward Magnifier, Sub-Bass +1 Oct, and a real-time K-weighted Session Ear Fatigue (TTS) Dose Tracker.

v2.0: AirPods Pro / Mimi Import & Wizard HealthKit & ISO 226

Import your existing Apple AirPods Pro 2 (Apple HealthKit HKAudiogramSample) or Mimi Hearing Test results in one click (with automatic 12–16 kHz studio extrapolation), or self-calibrate in 3 minutes with L/R pulsed warble tones and pink-noise synaptopathy checks.

Codebase Structure

Modular C++17 / JUCE 8 Architecture

truehear-studio-suite/
├── CMakeLists.txt
├── Source/
│   ├── Core/
│   │   ├── SharedEarProfile.h/.cpp          # 10-band ISO audiogram, notch, tinnitus & Darwin IPC sync
│   │   ├── MicroscopeEngine.h/.cpp          # 6-16 kHz -> 3-8 kHz dual-head Hann grain octave-down shifter
│   │   ├── GuardEngine.h/.cpp               # Blind-spot weighted harshness, sibilance & air trap detector
│   │   ├── BalanceEngine.h/.cpp             # 4-band L/R symmetry compass, phase correlation & ear-swap
│   │   ├── SafeMonitorEngine.h/.cpp         # Half-gain personal monitor EQ + BounceGuard(TM) offline bypass
│   │   ├── DensityAnalysisEngine.h/.cpp     # 12 mixing zones, crest factor, M/S FFT & waterfall heatmap
│   │   ├── MultiBusClashEngine.h/.cpp       # 24-Bark cross-bus psychoacoustic masking & clash detector
│   │   ├── InterInstanceStemRegistry.h/.cpp # Lock-free POSIX shared memory multi-bus audio ring buffer
│   │   ├── StemAuditionMatrix.h/.cpp        # Click-free individual, combo & clash-band stem auditioning
│   │   ├── FixSuggestionEngine.h/.cpp       # Instrument-aware mix fix recipes & reference delta calculator
│   │   ├── LogicPresetWriter.h/.cpp         # Binary .pst (GAME TSPP) & XML .aupreset Logic Channel EQ writer
│   │   └── ReferenceTrackManager.h/.cpp     # Multi-format reference track loader & loudness-matched A/B
│   ├── Plugins/
│   │   ├── MasterDensity/                   # aufx MsDn StTl
│   │   ├── EarProfileMap/                   # aufx ThEp StTl
│   │   ├── HFMicroscope/                    # aufx ThMc StTl
│   │   ├── SafeMonitorComp/                 # aufx ThSm StTl
│   │   └── MultiBusInspector/               # aufx ThIn StTl
│   ├── StandaloneApp/                       # Unified TrueHear Studio macOS application
│   └── Tests/                               # Headless DSP, Multi-Bus, Preset & Adversarial Stress Tests
└── Tests/E2E/                               # Automated End-to-End Requirement Verification Suite