RootlessViPER4Android

Output limiter (with selectable peak / soft-saturation modes), auto-loudness compander, bass boost, dual-band psychoacoustic bass exciter, stereo widener, crossfeed, virtual room reverb, arbitrary-response graphic EQ (AutoEQ import), and a scriptable Liveprog (EEL2) engine.

💜 Quality-of-life

Plain-language "ℹ️ what is this?" explainers on every section

Smart UI: irrelevant sliders hide automatically

Crash-safe DSP dispatch with built-in diagnostics

Works per-app, session-based — no audio HAL patching

🆕 Added & changed vs. upstream RootlessJamesDSP

Added in this fork:

🐍 16 native ViPER4Android effect sections (see table above) — including brand-new engine code for Dynamic System, ViPER Bass, Clarity, FET Compressor, Cure+, Field/Differential/Headphone Surround, Reverberation, Spectrum Extension, AGC & Speaker Optimization

🔊 Dual-band psychoacoustic bass exciter — two independently tunable harmonic bands (the second band hides until you enable it)

🛡 Selectable output limiter modes: classic peak limiter, smooth soft-saturation (tanh) mode, or fully off

🎧 446 official ViPER-DDC correction files bundled and auto-installed on first launch

ℹ️ Collapsible plain-language explainers on every effect section

🧰 Built-in crash diagnostics: native + JVM crash reports auto-copied to clipboard on next launch

Changed & fixed:

🔥 Tube simulator actually works now — upstream divided the drive value by 100 before it reached the engine (max ≈ 0.12 dB, inaudible); fixed and range extended to 24 dB

🐛 Fixed a crash when seekbars use a % unit label

🪄 Smart UI: Dynamic System custom sliders only appear in Custom mode; irrelevant controls stay hidden

🗂 All ViPER-equivalent sections renamed to their authentic V4A titles and reordered into the classic V4A layout under a dedicated header

➖ Removed the redundant Parametric EQ card (Arbitrary-response/graphic EQ covers it)

📛 App renamed to RootlessViPER4Android (installs alongside the original RootlessJamesDSP)

🆔 From v3.35.0 the package is this project's own — com.alienware377.viper4android.rootless, and com.alienware377.viper4android.rootful for the rooted build. Earlier releases still carried upstream's me.timschneeberger.rootlessjamesdsp, which this fork stopped being a long time ago. The rooted build is now called RootfulViPER4Android rather than confusingly shipping "Rootless" in its own name

🗺 Roadmap

✅ Shipped

Reorderable DSP chain — put the effects in any order you like

Interactive parametric equalizer — drag bands on the curve, rotary fine-tuning, live apply

Full echo / delay unit — ping-pong, filtered feedback, bit crushing, modulation, on its own knob panel

Chained Liveprog scripts — multi-select scripts, one card per script, chained in order

Custom effect groups — create, rename and delete groups, move cards between them, hide what you don't use

More reverb room types — Plate, Concert hall and Room alongside the classic ViPER model (#1)

ViPER classic limiter — a faithful re-creation of V4A's own limiter, lookahead and all

ViPER4Android-only mode — the original effect set, naming, processing order and limiter, with everything else switched off

ViPER4Android classic theme — the classic look, available with or without the mode

Library management for Convolver & DDC — search, sorting, hiding, groups, and downloading more profiles from public repositories

Idle battery fix — processing stands down when playback is silent, not just when apps release the audio session

Multiband distortion — pick frequency ranges to drive, with eight distortion characters, chorus, and a global mix, built on the interactive EQ editor with cutoff-type handles

Full maximiser — four limiting algorithms, with character, transient emphasis, true-peak detection, stereo linking and oversampling

Search, sorting & hiding on the presets screen — the same pull-down search, custom order, hiding and groups the convolver and DDC libraries have

Linear / minimum phase toggle — on both equaliser cards, since the two are merged into one filter before the engine sees them

Dynamic EQ — bands that only act while their own slice of the spectrum crosses a threshold, so taming a boom that happens on four notes no longer costs body on everything else; ships tuned for low boom, harshness and sibilance

Multiband stereo imaging — width chosen per frequency range rather than all at once, with a mono-below control, so the low end can be folded to the centre while the top opens up; mono recordings come through untouched

Impact (attack & sustain) — shapes how a note starts and how long it takes to die rather than how loud it is, per frequency range, so a held tone is left completely untouched while a drum hit can be sharpened or softened

Low end — a steep subsonic filter to stop inaudible rumble eating headroom, one knob for body, and a wide dip where recordings turn thick (mono-below lives in the imaging card and punch in Impact, so neither is duplicated)

Soft clipper — three curves for the maximiser's Character control, from one that bends immediately and adds density to one that stays linear until the very top and only clips peaks; a shape inside the maximiser rather than a second thing doing the limiter's job

Mid/side modes — the dynamic EQ can be pointed at the centre of the image or at its edges, so a de-esser can catch a vocal without dulling the reverb around it; the untouched half comes through bit-for-bit

Exciter — four ranges, each with its own amount, and five characters: three symmetrical ones that add odd harmonics and two lopsided ones that add even harmonics, which is the difference between a transistor sound and a valve one. The older two-band Bass exciter card is left in place so existing setups keep working

Vintage tape — wow and flutter as a genuinely modulated delay rather than a phase trick, gentle tape saturation, a bias control that runs the right way round (down is brighter and grittier, up is duller), and the head bump that makes tape masters sound weightier

Rooted mode — a Magisk module carrying this fork's own engine as a system-wide audio effect, so rooted devices run these effects rather than the stock JamesDSP set. Ships as RootfulViPER4Android, a separate app that installs alongside the rootless one. Legacy effect HAL, so Android 14 and below

🔜 Planned

Global "Poweramp-style" mode — process the whole output mix with Android's built-in effect API instead of audio capture: no capture permission, no persistent notification, and apps that block capture (Spotify) would work. Trade-off: only EQ/bass/limiter-class effects can run there — the ViPER effects need the capture engine. Deprecated by Google and device-dependent (works on many Samsungs, often not Pixels), so it'll ship clearly labelled as experimental.

Spectral shaper — dynamic taming of harshness and resonances, especially handy on bright IEMs

Match EQ — match playback to a target curve, pairing naturally with the AutoEq and DDC profiles already supported

Binaural upmix — build a surround bed from stereo, then fold it back to headphones through HRTF/BRIR convolution so sources can sit behind and above you. Headphones only; two speakers can't do this without crosstalk cancellation

AIDL effect HAL — a second module for Android 15 and newer, where the effect framework moved from the legacy plugin interface to a binder service. Not a port of the existing one: the engine has to be exposed behind a new interface and driven from fast message queues rather than a process callback

Rooted mode on Android 15+ — the effect framework moved to a binder service there, so the Magisk module above does not apply; that work is the AIDL item above

GitHub search for new profile sources — built but parked while its edge cases are ironed out; adding your own repository link already works

Built-in media player (after everything above) — a library browser in the spirit of jetAudio, with independent tempo and pitch control as well as combined speed, and a now-playing screen modelled on vintage turntables: platter wow and flutter, motor speed drift, surface noise and other period defects as deliberate, adjustable colour. Visual and behavioural reference: the iPad app Vinyl (demo)

Remember effect on/off states across a ViPER4Android-only mode round trip — your settings already survive, but effects switched off by the mode stay off when you leave it