What’s new
Changelog
What changed in each product, once it has actually shipped. Newest first.
SUS4 Plugins
One entry per released version of the plugin suite (macOS, Windows and Linux). Updating installs the latest version.
Version 1.4.0Current
Delays
- ExtremeDelay: real shimmer, real SUS chaos, real stereo. Pitch Shimmer now climbs in true octaves, SUS Chaos Depth really scatters the repeats, Reverse really plays backwards, and Ghost is a real pre-echo that arrives before the note. New Ping-Pong stereo mode and wet Width control. The SUS pre-echo lead is now 0–1 s. Smash no longer overwrites your Mix, Feedback and Reverse settings. The hidden auto-leveller is gone, so the Mix knob does what it says. 33 factory presets, none of which clips.
- RecursiveDelay: clean pitch spirals and real stereo spread. The SUS spiral is now a proper pitch shifter: each repeat is in tune and free of the old stutter. Spread pans the four delay lines across the stereo field, and Ping-Pong really alternates sides. Smash saturates each repeat without harsh aliasing. The SUS Pre-Lead echoes land where the display shows them. The hidden level-match is gone. 31 factory presets, none of which clips on normal material.
- Both delays have a real Bypass that keeps your session in time, tempo-synced echoes that land on the grid, and a display that draws the echoes the plugin actually plays.
Dynamics
- SmartGate: the spectral detector is real. The detector panel now shows the actual spectrum of the key signal and the band the gate listens to. The band has steeper filters and a new SC LowPass, so kick bleed no longer opens a snare gate. New SC Listen. Attack, Release and Hold now match their settings. The two channels are linked, so the stereo image holds. Drive no longer comb-filters at partial Mix and is much cleaner. Lookahead is accurate at every sample rate. SMASH adjusts the gate without overwriting your Threshold or Drive. 29 factory presets.
- Expander: oversampling, M/S and lookahead. New Range (0–80 dB), Lookahead (0–10 ms) and Stereo (Linked / Unlinked / Mid-Side) controls. Drive and the SUS wavefolder no longer alias, and low notes no longer distort. The key filter is steeper, so bleed stays shut out. Release times now match their settings. The Threshold, Attack, Knee and Hold controls now work in SUS mode. RUNAWAY no longer rewrites Threshold and Ratio, and the SUS presets stay below 0 dBFS. In the Audio Unit, where there is no sidechain input, the status bar now says so. 29 factory presets.
- Bond 609: a new engine with the character of the classic 33609. After a sustained passage the recovery slows, so the mix breathes on hits and settles on held sections. New Limiter section with its own ceiling, and new Link / Dual / M·S stereo modes. The Analog colour is more authentic: the grit grows with the gain reduction and the output iron thickens only the lows. SUS is now an upward expander that follows your Ratio, and its boost is held back so it does not lift peaks over the ceiling. The decorative header buttons are replaced by the real stereo mode switch, and the meters show real levels. 33 factory presets.
- Crimson: even-harmonic colour, as promised. The transformer now adds mostly second harmonic at every Drive setting, and the colour follows the level. Aliasing at high drive is gone. Below the threshold with Drive at 0 the signal passes untouched. SUS is a new "bloom" that thickens held notes instead of adding hidden level. Auto Gain now works in SUS. The whole panel scales with the window. 28 factory presets (was 20). Crimson also uses about a third of the CPU it did before.
- ChannelStrip: sidechain, M/S and four compressor types. The compressor now offers VCA, FET, Opto and Vari-Mu, with new Knee, Makeup and Mix. The compressor and the gate can be keyed from the sidechain input (VST3), with a key filter and SC Listen. The strip runs Linked, Dual Mono, Mid/Side, Mid-only or Side-only, with a 0–200 % Width. The gate gains Range, Attack, Hold and Release. The de-esser gains a Threshold. There are now Tube, Tape and Transistor saturation curves, which add harmonics without jumping in level and without aliasing. Auto role no longer overwrites your settings. It suggests a role instead. New resizable editor with an EQ curve drawn from the real filters. 33 factory presets.
Reverb
- GatedReverb: tight gates and a bloom that swells into the hit. The gate now opens and closes on time: a 100 ms release really is about 100 ms. Both sides of the reverb gate together, so a hit on one side no longer mutes the other. The SUS bloom now rises into the hit instead of peaking on it. New Pre-Delay, Stereo Width (M/S, 0–200 %), Drive and Low Cut controls. The skin's bypass key, which did nothing, is gone: use your host's bypass. Resizable editor. 28 factory presets.
Pitch and creative
- Harmonizer: up to eight natural-sounding voices. A new engine keeps the singer's formants, so harmonies sound like a second singer rather than a chipmunk. Each of the eight voices has its own interval, level, pan, formant, detune and delay. Intervals follow a key and scale, or can be fixed semitones. New Formant Keep and Formant Shift controls. The dry voice is now delayed to line up with the harmonies. The latency is a fixed 23.5 ms, reported to your host. The auto-gain that fought your level controls is gone. 31 factory presets (was 21). It uses less CPU than 1.3.1 did.
- Humming Composer: follows your voice more accurately. The pitch readout is now within about 1 cent. Note changes are picked up in about 20 ms, and wrong or in-between notes no longer appear. Auto key now gets tunes that rest on the 3rd or 5th right. Four sounds (Pad, Keys, Strings, Organ) with a new Tone control, cleaner oscillators and a real metronome. New Sync follows your host's tempo and bar grid. MIDI goes out on three channels (chords, bass, melody), lined up with the audio. The output stays under −1 dBFS. 24 factory presets. Uses a fraction of the CPU it did before.
- Fragmenter: tempo sync, a real Mix and honest bit depth. A new Tempo Sync slicer with Division (1/64 to 1/2, triplets and dotted), beat repeat, slice gate and grid scatter. Mix at 0 is now truly dry. The crusher no longer runs about 66 ms late, and "8-bit" really sounds like 8 bits. Rate behaves the same at every host sample rate. The new Anti-Alias Filter gives a clean sample-rate reduction when you want one. SUS now crushes quiet passages as well as loud ones, instead of silencing them. The two channels are processed separately. Real Bypass, new metering, and 44 factory presets (10 new).
GuitarAmp
- Real cabinets and your own IRs. The cabinets are now convolved with nine modelled cabinet impulse responses, and they really sound different from each other. Load your own WAV impulse responses. They are saved with your session.
- A modelled tone stack (the classic passive Bass / Mid / Treble circuit) plus a separate Presence control, a two-stage oversampled preamp with far less aliasing at high gain and in SUS, and a new noise gate. 26 factory presets, rebuilt for the new engine.
- The new engine uses about the same CPU as the old one: no factory preset costs more than 1.3 times as much, and most cost about the same or less.
Across the updated plugins
- Resizable editors with a UI size picker, the shared preset browser (with your own presets) and A/B compare.
- Honest controls and meters. Every control changes the sound, every readout shows the value the plugin really uses, and the meters and curves are drawn from the audio engine, not from animation.
- Output loudness (LUFS) and true peak in every updated plugin.
- Accurate latency. Every updated plugin reports its true latency to your host. Several have more latency than before, for example Crimson and Bond 609 (63 samples) and Harmonizer (23.5 ms). Your DAW's delay compensation keeps everything aligned.
Sessions and presets
- Sessions saved with earlier versions open. Every existing control keeps its place, so saved sessions and automation load. New controls load at settings that leave your sound alone where possible (for example, the Bond 609 limiter off and stereo mode Link, and the SmartGate SC LowPass and SC Listen off). Limiter sessions saved with 1.2.3 still open exactly as saved.
- Rebuilt plugins sound different. Where the old behaviour was a fault (late gates, fake shimmer, hidden level changes, controls that did nothing), an old session now plays the corrected sound. Harmonizer maps the old 3rd / 5th / 7th voice setting to the same voices. Crimson SUS sessions play quieter, because the hidden SUS boost is gone. Each plugin's manual lists what changed.
- Factory banks were rewritten for SmartGate, Expander and GatedReverb, so host program-change numbers for those plugins have moved. Fragmenter and Harmonizer keep their existing preset numbers and add new presets after them.
Version 1.3.1
The free trial now starts on our website
- The 7-day free trial is started at 4chords.studio/plugins. A card is needed, and it is not charged for 7 days. Cancel before the trial ends and you pay nothing. Your licence key arrives by email straight away and unlocks every plugin in the suite.
- Without a licence key, the plugins pass audio through untouched. From the first time you load one, an unlicensed plugin passes audio through bit for bit, delayed only by its reported latency, so your session stays aligned and sounds as if the plugin were bypassed. There is no noise, no muting, nothing added.
- The licence panel in every plugin has a Start your 7-day free trial button (it opens the website in your browser), the field to paste your licence key or activation link, and a Buy button. The banner at the bottom of each plugin has the same trial button and Enter licence key.
- 1.3.0's built-in 7-day trial, which ran without a card, is gone. Plugins that were activated keep working exactly as before.
Licence agreement
The end user licence agreement is now version 2.1: section 5.2 describes the website trial (card needed, not charged for 7 days) instead of the built-in trial.
Version 1.3.0
Trial and activation (new)
- 7-day full trial, then audio passes through untouched until activated. During the trial every plugin works exactly as it does when licensed. After day 7 an unlicensed plugin passes audio through bit for bit, delayed only by its reported latency, so your session stays aligned and sounds as if the plugin were bypassed. A trial never ends in the middle of a session, and activating resumes processing straight away, without a reload.
- Paste-a-key activation inside every plugin. The activation panel and the Trial banner now have an Enter licence key field. Use it if the sus4:// magic link does not open on your machine.
- An offline machine never loses audio because of licensing. Only a refund or chargeback revokes a licence.
Existing customers: licence store migration (macOS)
- macOS 14 and earlier: your activation is copied across automatically the first time a SUS4 VST3 loads. You do not need to do anything.
- macOS 15 and later: open SUS4Suite.app once (or load any SUS4 Audio Unit) and the activation is copied across. If a SUS4 VST3 still shows as unlicensed on macOS 15, paste your licence key into the plugin's activation panel (Enter licence key), or click your activation link again. Use the same key you already have.
On macOS the VST3 plugins now keep their licence in ~/Library/Application Support/SUS4/, outside the AUv3 app-group container. Reading that container from a DAW made macOS 15 ask "would like to access data from other apps", and the plugin waited until someone answered.
Audio Units, Windows and Linux are unaffected.
Fixes you will notice
- macOS Audio Units now run at your session's sample rate. Every SUS4 AU ran its DSP at 44.1 kHz whatever the host rate, so at 48 kHz (Logic's default) or 96 kHz, times, filter frequencies and tempo sync were all off. AUs now take the rate the host negotiates.
- Gate: the Release control is now accurate (a 100 ms setting measured 1,082 ms), and Drive no longer aliases.
13 improved plugins
- ParametricEQ: shelf, cut, notch and tilt filter types; oversampling; presets; spectrum display.
- DynamicEQ: presets, sidechain, spectrum, M/S.
- Limiter: auto-release, target LUFS and true-peak ceiling, M/S, algorithm choice, preset browser.
- Compressor: anti-aliasing, lookahead, presets.
- Multiband: auto-gain that no longer hides threshold/ratio changes; oversampling.
- Spark3A: M/S, preset browser, metering.
- Strike76: resizable UI, M/S, LUFS, multi-meter view.
- Aurum670: fixed an AU launch failure; resizable UI; metering.
- Lume2A: in/out meters, program-dependent release, H2 warmth.
- ExtremeReverb: real pitch-shifted shimmer, stereo width; removed the misleading "CONVOLUTION" label.
- Enhancer: bypass now works; the 50 Hz sub stage no longer hurts bass material.
- DrumAlign: sidechain controls in the UI, presets, resizable UI.
- Gate: see Fixes above.
Across the suite: a shared preset browser with A/B compare, resizable and scalable UIs, shared in/out, gain-reduction and LUFS/true-peak metering.
Licence agreement
The EULA is rewritten (version 2.0, 27 September 2026) in plain English. It replaces the old text that described the software as an alpha release.
Version 1.2.3
Changes you will notice
- macOS Audio Units: hosts now see the real version. Every SUS4 Audio Unit reported "Component Version 1.0.0" to hosts, whatever release was installed. Logic Pro compares that number with its Audio Unit cache to decide whether a plugin changed, so an update never looked new to it. Each Audio Unit now reports the suite version (1.2.3 reports 1.2.3), so Logic and auval see an update as a new version. Audio and saved sessions are unchanged.
Version 1.2.2
Changes you will notice
- Multiband: the panel is correct the moment it opens. Before the host sent its first values, the knob readouts disagreed with the graph and band cards drawn right next to them: THRESH read -60 dB against the graph's -20 dB, RATIO read 1.0:1 against 4.0:1, PARALLEL MIX read 0% although the plugin ships 100% wet, and two different sets of crossover frequencies were on screen at once. The panel now draws from one table of defaults, and double-click reset-to-default uses the same table. Display only: no audio or saved-session behaviour changes.
- Multiband: the advanced controls are easy to find. The band ratios, attacks, releases, crossovers and SUS controls used to be hidden behind clicking the "4" four times. There is now an Advanced button in the header, and Close puts the drawer away. The drawer sizes itself to the window, so at 1200x740 it no longer cuts off the band cards' accent bar, and at 960x590 it no longer covers the band cards (anything taller than the space scrolls). The status line no longer claims a fixed "44.1 kHz / 32-bit", which was wrong whenever the session ran at another rate.
- macOS: VST3 plugins show their version. Every macOS .vst3 bundle had a blank version in its Info.plist, so Finder's Get Info, and any host that reads the bundle rather than asking the plugin, showed no version. They now show the suite version.
- Linux: the download contains only what you install. The Linux tarball used to carry build-time test programs (SUS4_Tests and five *_metering_verify probes) next to the plugins, activator and install.sh. They are gone, and the build now fails if one ever gets packaged again.
Version 1.2.1
Changes you will notice
- Logic Pro and GarageBand (AUv3) automation. Dragging a knob now reaches the host as one gesture: a touch, the value changes, then a release. Before this release the AUv3 plugins sent a separate untyped edit for every mouse movement. Touch/latch automation and undo in AU hosts now work the way they already did in VST3 hosts.
- GuitarAmp: new Output Trim control (±12 dB, applied after the amp and cabinet). Four factory presets that clipped close to 0 dBFS (Singing Lead, Brit Stack, Modern Metal, Modern Hi-Gain Rhythm) now leave about 2 dB of headroom. Their drive and voicing are unchanged. Sessions saved with older versions open with the trim at unity.
- SmartGate: Inverse Gate works. The control was connected but had no effect on the sound. It now works with SUS Mode on or off. A session saved with SMART SMASH engaged also reopens with the effect in place.
- Gate: a session saved with GATE SMASH engaged now reopens with the effect in place.
- Enhancer: a session saved with ENHANCE SMASH engaged now reopens with the effect in place.
- GatedReverb: the SUS Anti-Gate Depth control now changes the sound when Pre-Verb is active, which is the default SUS setup. It was connected but had no effect.
- Support contact. The Settings/About panel and the licence screen in every plugin now show [email protected] and our response commitment. SUPPORT.txt ships inside the macOS app, and the Windows and Linux READMEs carry the same details.
Apps
The current App Store version of each SUS4 app and its release notes, most recently updated first.
SUS4 Practice
Version 1.1.2 ·
Stability and performance improvements.
- 1.1.1 · — Lifetime purchase option and reliability improvements.
On the App Store since
SUS4 Recorder
Version 1.1.2 ·
Reliability improvements.
On the App Store since
SUS4 Scale Lab: Guitar Scales
Version 1.1.2 ·
Lifetime purchase option and reliability improvements.
On the App Store since
SUS4 Sketchpad: Song Ideas
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
SUS4 Time Trainer: Rhythm
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Backing Tracks: Jam
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
SUS4 Capo Calc: Transpose
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 DAW Help: Shortcuts
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
SUS4 Drum Pad: Beat Maker
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
SUS4 Ear Daily: Ear Trainer
Version 1.1.1 ·
Lifetime purchase option and reliability improvements.
On the App Store since
SUS4 Loop Builder: Looper
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
SUS4 Mix Check: Mix Analyser
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Setlist: Gig Manager
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Sight Reader: Practice
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Transcribe: Audio to Tab
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Vocal Warmup: Singing
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 BPM
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Chord ID
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Metronome
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Pitch Pipe
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Score: Sheet Music Scan
Version 1.1.3 ·
Stability and performance improvements.
On the App Store since
SUS4 Tuner
Version 1.1.2 ·
Stability and performance improvements.
On the App Store since
Account and website
Changes to the free trial, billing, checkout and your account.
The plugin free trial starts at checkout
Start your 7-day free trial on the plugins page. A card is needed but not charged for 7 days; cancel before the trial ends and you pay nothing. Your licence key arrives by email straight away.
Cancelling keeps what you paid for
Cancelling a subscription now keeps your plugins working until the end of the period you've already paid for. Your account page shows the date it stops, and you can change your mind before then.
Redeem a SUS4 code
Bought the SUS4 plugins through a marketplace? Enter your code at 4chords.studio/plugins/redeem and your licence is emailed to you.
A true 7-day free trial
Every monthly and annual plan now gets the full 7 days before your card is charged — timed to the trial's own end, not a fixed day-6 guess.
Pick up an unfinished checkout
If you start checking out and don't finish, we can now send you a link back — we ask for your email before the Stripe redirect instead of only after.
Tell us why you left
Cancelling now optionally asks why, so the things that actually make people leave get fixed instead of guessed at.