Maxxlorr Tracker v4.74

1. Welcome

Maxxlorr Tracker v4.74 (MLT) is a complete FastTracker II-style music tracker, extended with a visual performance engine (Visual Lab), per-track and master DSP racks, a full FT2 instrument editor (envelopes, sub-samples, NNA) and spectral/phase tagging tools (TagStudio). Everything lives in a single HTML file: no installation, no server, no network dependency.

This manual walks through the whole application: it starts from the general interface, dives into each editor, then provides complete reference tables (pattern commands, DSP devices, visual effects, keyboard shortcuts).

2. Quick start

1. Open the HTML file in your browser.
2. Click ▶ Play (or left Ctrl): the demo module starts. Adjust the tempo with the BPM and Speed fields in the transport bar.
3. Enable edit mode with Space (Edit Mode ON), place the cursor in a note column and play with the AZERTY/QWERTY keyboard: the bottom row (Z S X D C…) gives the lower notes, the top row (Q 2 W 3 E…) the upper ones, at the current octave (Oct).
4. Import your own sounds via the IMPORT menu (sample, XM, IT, MOD, S3M, MID, MLT), or generate a complete General MIDI bank from the MIDI menu.
5. Save your work with EXPORT → .MLT (complete native format), or export to .XM/.IT/.MOD/.S3M/.MID for other trackers.

3. General interface

The screen is organized in five zones:

• Top bar (topbar) — transport (Play, Stop, Play From), BPM/Speed/ Octave, pattern selector, IMPORT/EXPORT menus, NEW MODULE, latency and visualizer FPS indicators.
• Left panel "SONG & MEDIA" — the 128-instrument list, sub-samples and the pattern sequencer. Collapsible via its tab.
• Central view — four tabs: Pattern, Instrument, Sample and Mix.
• Right panel — collapsible; switches between Pattern Edit (selection tools, editing options) and Visual Lab using the double-arrow button ◄ ► aligned at the right of the panel title.
• Meter row (bottom) — global Peak/RMS bar with AGC correction gauge, spectrum, phase meter and per-track waveform views (track views).

The status line at the bottom reports the result of every operation (imports, exports, errors, contextual hints). Hover the controls: almost all of them carry a detailed tooltip.

Figure — the MLT v4.74 interface (real screenshot, downscaled)

Figure — meter row: Peak/RMS + AGC gauge, spectrum, phase meter, track view (waveform, spectrum and phase images are bitmaps)

Peak / RMS + AGC

AGC attenuating ◄

Spectrum

Phase meter

Track view CH 01

4. Transport and playback

During playback the pattern view follows the playing row. The sequencer, however, does not auto-center: you can scroll it freely and queue a deferred playback position by clicking it; re-centering only happens when you click the timer.

5. Pattern sequencer

The sequencer (left panel) defines the pattern playback order: each row is a position referencing a pattern number.

Operations

• Add / Del / Copy / Duplicate — insert, delete, copy or duplicate the selected position.
• Click a position — selects it for playback/editing without forcing the list to scroll (the view stays where you put it).
• Drag & drop — reorders positions.
• Position label — next to each number, an editable text field (20 characters) names the position ("intro", "chorus"…). Labels are saved in the .MLT file.
• Range markers / repstart — define song-level playback loops.

Current-pattern buttons

+ Pattern creates a new pattern, Clone duplicates the current one, Clear erases it, +Row / −Row insert or delete a row at the cursor position.

6. Pattern editor

Each track is a column of cells. A note cell contains:

• Note + octave (e.g. C-4) — typed on the music keyboard;
• Instrument (2 hex digits);
• Volume column (2 hex digits, commands 10–FF, see the reference);
• Effect columns — up to 3 per track, each showing TPVV: 1 command letter + 2 parameter digits (classic commands) or 4 digits for live DSP control (see §8.4).

Editing and navigation

• Space toggles Edit Mode (ON = played notes are written; OFF = audition only).
• CapsLock inserts a Note Off (==); Backspace erases the cell and pulls rows up; Delete clears the cell.
• Arrows / Tab / Enter: navigation; the view scrolls automatically to keep the cursor visible.
• Row numbers are displayed in decimal.

Selections (Pattern Edit panel)

• Sel Line / Sel Track — select the whole row or track; the highlight stays visible during and after playback.
• A. All / B. Pattern / C. Selection — set the scope of editing operations (copy, paste, transpose…); C. Selection is the default.
• Track names — the "CH 01"… headers are editable (up to 12 alphanumeric characters); names are stored in the .MLT file.

DSP automation recording

In Edit Mode ON, any slider or knob movement on a track DSP is converted into a 4-digit TPVV command at the cursor position (T = DSP number, P = parameter number, VV = hex value), whether playback is running or stopped. This is the fastest way to write automation.

The collapsible FX rack at the bottom of the pattern view offers a second way to record commands: its Pattern FX helper lists every command with its syntax (0xx | 00-FF | Arpeggio…) — picking an entry writes that command at the cursor position when Edit Mode is ON. It is the handiest way to discover the syntax while composing.

7. Melodic Assistant

The Melodic Assistant lives at the top of the right panel (Pattern Edit). It composes musical material for you — a single part or coordinated chords, bass, lead and drums on four adjacent tracks — straight into the pattern or the current selection.

Proposal settings

Phrase & groove

Instruments & drum map

Assign an instrument to each role (Chords, Bass, Lead, Drums) and to each drum piece (Kick, Snare, Closed hat, Open hat) so the generated parts land on the right sounds immediately.

Actions

Generate builds a proposal, Audition previews it, Variation derives a variant from the same seed lineage, Apply writes it into the module, Undo reverts, Stop silences the preview. The detected/used harmony is displayed as a chord chain (e.g. C - Am - F - G).

8. Pattern command reference

Commands are typed into the effect columns of the pattern editor. The built-in helper (help icon in the editor) lists every command with its syntax; the tables below reproduce that reference exhaustively for v4.74.

8.1 Classic commands

8.2 Exx extensions

8.3 IT extensions (N, O, U, Y, Z)

These commands extend Impulse Tracker compatibility:

Zxx executes an IT MIDI macro: Z00–Z7F passes the parameter to the macro selected by OFx, Z80–ZFF runs a fixed macro. The default macros drive the instrument filter cutoff/resonance; channel-voice MIDI messages are forwarded to the active MIDI output (SysEx is never requested).

8.4 MLT commands (Mxx) and 4-digit DSP control

4-digit DSP control — TPVV

When the first character of an effect column is a hex digit (0–F), the cell is not a classic command but a DSP setting: T = DSP index in the track rack, P = parameter index, VV = hex value. Example: 0140 sets parameter $1 of DSP $0 to $40. A classic 3-digit cell never shows a leading 0, so it cannot clash with this mode.

8.5 Visual Lab: MDx / MEx / MFx

8.6 Volume column

The volume column also directly accepts a volume value 10–50 (16–80). It is independent of the effect columns and applies to the cell's note.

9. Instruments

MLT manages 128 instruments, each holding up to 16 sub-samples mapped across the keyboard — enough to build drumkits and multi-sampled instruments. The instrument list lives in the left panel; Edit instrument and Edit sample open the corresponding views.

Sub-samples

The "Instrument sub-samples" list shows the 16 slots; the active slot is highlighted and loaded slots are marked in green. Each sub-sample has its own name, loop, volume, finetune and relative note.

Envelopes

Four point-editable graphic envelopes: volume, panning, filter and pitch. Each has working checkboxes: enable (On), loop and sustain — all take effect immediately during playback. Commands MA3–MA6 and MA7–MAE toggle these envelopes from the pattern (§8.4).

Instrument parameters

Keyboard map and AdLib OPL

The piano map assigns sub-samples to keys. When the GENMIDI/OPL bank is active (§14), an AdLib OPL2 instrument editor appears (FM operators, algorithms, feedback).

10. Sample editor

The Sample view edits the active sub-sample: a large waveform display (stereo samples are displayed and edited in stereo, with no forced mono conversion), an info line (format, length, loop), then the button groups below, grouped by theme.

Figure — sample editor (waveform display is a bitmap)

Sample name Loop ForwardStart End X-Fade Volume x

Play sample((O))CutCopyPasteTrimApplyNormalizeReverseSmoothSpectral TagPhase TagSPLITTER

+ Marker- Marker02 @ 44100Play markerStop markerC2PDetect transientsSensitivity

Sample playback

Play sample, ((O)) (converts the mono sub-sample to stereo), Play marker / Stop marker.

Editing

Cut / Copy / Paste / Trim, Undo, Apply (applies the "Volume x" gain), Normalize, Reverse, Smooth, Phase Invert. Zoom selection / Zoom all frame the view.

Loops

Loop start/end in frames, none / forward / ping-pong type, with on-the-fly loop crossfade to avoid clicks and pops. Commands M00–M9F drive loop geometry during playback (§8.4).

Markers (up to 256)

+ Marker / − Marker, selection list, frame-accurate position, Detect transients (with Sensitivity) to auto-mark transients, and C2P which copies the selected marker as an Sxx command into the effect column (Edit ON): during playback, S00–SFF re-triggers the sample from the matching marker — slice-style rhythmic chopping.

Advanced tools

Mono synth

The Monophonic sample synthesizer panel reshapes the sample with a remix oscillator (mix, selection render) to resynthesize sounds from fragments.

11. DSP racks and meta devices

Every track owns a DSP rack (up to 16 devices), and the Master Track owns its own rack. Devices can be added, removed, enabled/disabled and moved at any time, even with Edit Mode OFF. On/off state is also pattern-controllable: MB0–MBF (track rack) and MC0–MCF (master rack); parameters are driven by 4-digit TPVV commands, and master parameters by Jxx.

Available devices

Master rack presets: Default, Clean Headroom, Gentle Clarity.

Inertia (common parameter)

Every device — except the Meta Visualizer and the Router — ends with a common Inertia parameter (0–100 %, default 72 %). It sets the transition speed of pattern automation: low values make parameter changes glide smoothly over time, high values make them snap almost instantly. Inertia applies to TPVV automation and to GUI moves alike, so a single device can serve both gentle sweeps and abrupt switches.

Meta devices

12. Mix view and DSP Transfer

The Mix view (4th tab, after Sample) presents the console: one strip per track with fader, meter, DSP activity LEDs and an editable track name, plus the master strip. It is the right place to balance the mix without stopping playback.

DSP Transfer

From the Mix view, a device's ◄ ► arrows move it to the adjacent track while rewriting the whole module's automation:

• MB? commands and 4-digit TPVV commands are re-indexed to the target track;
• migration only happens if free effect columns exist (3 maximum per track);
• the transfer is transactional: it runs asynchronously (64-row slices, no UI freeze) and is only committed if complete — otherwise nothing changes;
• the Router device is excluded (its wiring would be meaningless on another track).

13. Visual Lab

The Visual Lab turns MLT into a music-driven visual performance instrument. Open it with the ◄ ► button at the right of the right panel's title: the panel switches between Pattern Edit and Visual Lab. The visualization frame adapts to the panel width and can composite several scenes.

The 8 slots

Eight typed slots (0–7) compose the scene. Each slot provides:

• a checkbox (left) enabling it — all are off by default;
• a dropdown of 16 effects numbered 0–F;
• a randomize button (right) picking a random effect;
• four mini-knobs of parameters (randomizable via MF8–MFB).

A global randomize button below the lists randomizes all 8 slots in one pass. A Meta Visualizer (§11) can drive the whole rig; the sync is immediate and bidirectional — the latest event (pattern, device or click) wins, with no source priority.

Pattern control

The MDx, MEx and MFx commands (§8.5) toggle slots, move the focus, select effects and randomize — locked to the pattern row. When a Visual Lab command originates from a track, that track's audio modulates the slot's effects (targeted audio-reactivity).

Effect catalog (16 per slot)

Webcam, game and recording

• BACKGROUND effect 9 (WEBCAM VIEW) uses the webcam — non-mirrored image, browser permission requested.
• The 2D LAYER OMEGA RACE is a playable game embedded in the visualizer.
• Video export (§15) records the Visual Lab performance in MP4 or WebM, synchronized with the audio render.
• On first launch, shader compilation can take a few seconds: a progress bar is displayed while the Visual Lab loads.

14. MIDI

Inputs / outputs

MLT uses the Web MIDI API: select your input and output devices in the MIDI section (Audio/Perf and menus). MIDI input plays instruments, records notes in Edit Mode and feeds MIDI Learn.

MIDI Learn

Right-click a control (slider, knob, transport button, instrument or DSP parameter) to open the MIDI Learn dialog:

• Modes: absolute CC, 14-bit CC, relative (two's complement, sign-magnitude, binary offset), pads in trigger / toggle / momentary;
• Options: soft takeover (no value jumps), invert, linear or logarithmic curve, sensitivity;
• Targets: transport, instrument parameters (volume, pan, finetune, fadeout, vibrato, filter envelope cutoff/resonance), per-track DSP parameters;
• mappings are stored in the project and saved inside the .MLT file.

General MIDI sound banks

Importing .mid

When a MIDI file is imported, each program is mapped to the right General MIDI instrument; if channel 10 is used, a drumkit (from the GeneralUser-GS kits) is installed and assigned to channel 10.

Exporting .mid

Each instrument is placed on its MIDI CH channel (§9) — set an instrument to channel 10 to export it as percussion.

15. File import and export

IMPORT

EXPORT

16. TagStudio: Spectral Tag and Phase Tag

Two marking tools, opened from the sample editor (Spectral Tag and Phase Tag buttons). Each one stops playback and opens a dedicated window overlaid on the interface.

Spectral Tag

Embeds an image into the sample's spectrum (spectral steganography): the message appears in a spectrogram without a clearly audible change. The processing runs in a Web Worker with an adjustable operation budget (60 / 120 / 240 M): the interface never freezes.

Phase Tag

Mixes into the sample an XY shape visible on the phase meter: text, image, 15-second video or 3D object (locally bundled Three.js — no network access). A discreet visual signature, ideal for tagging your exports.

17. Audio / Perf

The Audio/Perf panel gathers every audio engine setting. All its elements remain visible at every display scale.

Buffer size

Each size is displayed with its time and memory equivalents (2 channels × 4 bytes):

The smaller the buffer, the lower the latency — and the higher the risk of crackling on a busy machine.

Mixer / Mastering

Latency / Period

The latency line shows the real delay between an action and its audio output (keep it as low as possible without crackling). Period is the audio scheduler's update interval: Auto or 5–50 ms — the smaller it is, the more responsive note input, MIDI and the GUI feel (at the cost of CPU).

AGC and levels

The AGC (automatic gain control) only attenuates: it protects against clipping without ever amplifying beyond the set level. Its correction gauge, below the Peak/RMS bar, starts at the master volume slider position and moves left while attenuating, then returns to the start point as the gain is restored. The vertical meters and their clip LED follow the same logic as the main bar: the LED never lights up because of the AGC. Peak/RMS calibration matches the reference trackers (MilkyTracker, OpenMPT, FT2): a module that does not clip there does not clip here.

18. Keyboard shortcuts

Right-click opens contextual menus (MIDI Learn on controls). Tooltips document every button on hover.

19. Troubleshooting and FAQ

The sound crackles

Increase the buffer (§17), set Period to Auto, close greedy tabs, and check that the Visual Lab is not stacking too many 3D slots.

Everything sounds over-compressed compared to other trackers

Check Amplify and Limiter (§17): amplification pushes into the limiter. Output calibration follows the reference trackers; lower Mixer vol if needed.

The Visual Lab is slow to open the first time

That is shader compilation: a progress bar is shown. Subsequent openings are instant.

The webcam does not appear

The browser asks for permission the first time WEBCAM VIEW is used; check the site's permissions (address bar icon).

My Mxx / TPVV command vanished from my XM export

That is by design: MLT commands are not convertible (§15). Keep a .MLT version as your master file.

EF0 no longer does formant filtering

Correct: EF0/EF1 = IT phase surround. Use the Easy Formants DSP (§11), controllable live via TPVV commands.

A "join is not a function" error message

Fixed in v4.74 (SF2 imports, Play From); if you still hit it, note the exact action and reload the page — your module is safe as long as you have not overwritten it.

20. Credits and licenses

• Freedoom GENMIDI.op2 — OPL instrument bank, BSD-3 license.
• OPL3 core — derived from doomjs, MIT license.
• Three.js — MIT license, bundled locally (no CDN required).
• GeneralUser-GS — SF2 bank by S. Christian Collins, downloaded on demand for the MIDI Library and drumkits.
• Features inspired by MilkyTracker (mixer vol, amplify, limiter) and OpenMPT (latency/period, Amiga A500/A1200 filters).

Maxxlorr Tracker is a single self-contained file; please keep these notices when redistributing.