Basslines that write themselves. The part most people miss is that you can drag the MIDI straight out, or now play it into your own synth live.
Now two plug-ins, one licence: REHEAT the instrument, and REHEAT MIDI DRIVER, which plays your own instruments with REHEAT's line. This page is the manual for both. It is kept up to date here, so there is nothing to re-download when something changes. Last updated 8 August 2026.
REHEAT writes acid basslines you can drag straight out as MIDI, or play live through your own synth. Try the whole thing free in your browser first, no install and no account. One purchase covers every format, REHEAT and REHEAT MIDI DRIVER on a single key.
The 30 second version
This is the bit worth knowing
REHEAT is a writing tool as much as an instrument. When you have a line you like, drag the MIDI straight into your DAW and use whatever synth you want. You are not stuck with REHEAT's own sound.
Because you are exporting notes rather than audio, none of the silent-bounce trouble that affects the self-playing instruments applies here. The notes are just notes.
The step editor
Accent and slide are what make an acid line sound like acid rather than like a scale. A line with neither is just notes in order.
Making it write something different
AUTO-MUTATE keeps nudging the line as it plays, so it evolves instead of looping. Turn MUT RATE down if it is changing too fast to work with.
Prefer to play it live? Use REHEAT MIDI DRIVER instead of dragging. See the next tab.
What REHEAT MIDI DRIVER is
It is REHEAT's pattern engine with the synth taken out. It makes no sound of its own. Put it in front of any instrument you already own and it plays your sound with REHEAT's line, live, with no dragging and no bouncing. Your one REHEAT key unlocks it.
Where it goes: the MIDI slot, not the instrument slot
REHEAT MIDI DRIVER is a MIDI effect, so it sits ahead of an instrument, never in the instrument slot itself.
Press play. REHEAT writes the line, your instrument plays it.
FOLLOW MIDI: locking the line to your beat
A MIDI effect has no audio input, so it cannot listen to a drum bus the way REHEAT's sidechain FOLLOW does. Put a MIDI clip of your kick on the same track, ahead of the driver, and turn FOLLOW MIDI on. It locks the phase of its grid to those notes without ever restarting the pattern, and the notes pass through to your instrument so nothing is lost.
NUDGE, OCTAVE and DARKNESS
NUDGE shifts the whole pattern earlier or later by whole steps, up to eight either way, for when the line lands on the wrong foot against your groove. OCTAVE transposes it; DARKNESS changes which notes it writes, exactly as in REHEAT.
No drums come across. REHEAT's kit is synthesised audio, not MIDI notes, so the driver sends the bassline only.
A note keeps ringing
Make sure you are on the latest build, shown on the faceplate. If a note still hangs it is almost always the instrument after it: try a plain sound with a short release, and check nothing else in the MIDI chain, such as an arpeggiator with Latch on, is holding notes.
It will not load on my Mac at all
Fixed. The first build was mistakenly stamped with a minimum of macOS 26, so on anything older macOS refused to load it and it never appeared in Logic. The current build sets the minimum to macOS 11, so it runs on every Mac back to Big Sur.
Re-download from your Gumroad library. Your key is unchanged. In Logic it shows as v1.0.1 or later, which is how you know you have the corrected one.
Knobs slide around on a phone or tablet
Known, on the browser demo, and on the list. On a desktop browser with a mouse it behaves.
Is there an iOS version?
No, and no date promised.
Where is my licence key?
In your Gumroad receipt email, and on your Gumroad library page. There is a separate key for each instrument, so if you bought the Collection you have three of them.
It is silent and asking for a key
That is normal. Every instrument stays silent until it is unlocked. Paste the key on the first screen and press UNLOCK.
Do I have to activate every format separately?
No. One activation covers the AU, the VST3, the AAX and the Standalone on that machine.
If your DAW blocks the internet check, activate once in the Standalone app and the plug-in versions unlock along with it. All formats share the same activation.
Does it phone home? Do I need to stay online?
No, and no. It checks the licence once, when you first activate. After that the activation is written to a file on your own machine and it never contacts a server again. You can take the machine permanently offline and it keeps working.
On macOS the record lives at ~/Library/Tunary Instruments/REHEAT/license.json. The
installer never touches that file, so updating never costs you your activation.
My key was rejected
Send me the key you are using and the email address you bought with, and I will sort it at my end. james@tunary.io
The easy way
Download the installer from your Gumroad library and double-click it. It puts the Audio Unit, the VST3 and the AAX where every host looks for them, and you can untick any format on the Installation Type screen. macOS will ask for your password, which is normal for the shared Plug-Ins folder.
Installing by hand
The download has two plug-ins: REHEAT and REHEAT MIDI DRIVER. Copy both of each format. Use the folders at the top level of your disk, not the ones inside your home folder. In Finder press Shift Cmd G, paste the path, and drag the files in.
Tunary .component files → /Library/Audio/Plug-Ins/Components/.vst3 files → /Library/Audio/Plug-Ins/VST3//Library/Application Support/Avid/Audio/Plug-Ins/They load in different slots: REHEAT ORIGINAL on an instrument track's Instrument slot; REHEAT MIDI DRIVER in the MIDI FX slot at the top of the channel strip, above the instrument. The MIDI DRIVER has no Standalone, since a MIDI plug-in has nothing to play on its own.
The one that catches people. There is a similar folder inside your home folder that starts
with ~. Logic and Final Cut read both, but DaVinci Resolve and Premiere Pro only read
the top-level one, so a plug-in put in the home-folder version simply never appears in them.
Quit your host first
Fully quit your DAW or editor with Cmd Q before installing, then reopen it. Hosts only look for new plug-ins when they start.
What it runs on
macOS 11 Big Sur and later, Universal, so native on both Apple Silicon and Intel. Signed and Apple notarised, so macOS opens it with no security warning. Windows is VST3, 64-bit, Windows 10 and up. The AAX for Pro Tools is Mac only, and it comes in the Mac installer rather than the zip, because it has to go into a folder the zip cannot write to.
Windows says "Windows protected your PC"
The Windows builds are not code-signed, so SmartScreen warns on first run. Click More info then Run anyway. You do it once. A Windows signing certificate runs to several hundred dollars a year, which is a lot for a small label, so for now that warning is the honest trade.
Also, before you unzip: right-click the zip, choose Properties, tick Unblock, then extract. Windows tags anything downloaded and copies that tag onto every file inside.
Where does it show up in my DAW?
Under Tunary Instruments, not under the product name.
Not there at all in Logic? Logic Pro > Settings > Plug-in Manager, search for it. If it is unticked, tick it. If it failed validation, select it and click Reset & Rescan Selection. Usually it just means Logic was open while you installed.
Pro Tools
REHEAT ORIGINAL is an instrument, so it goes on an Instrument track, in the first insert slot. DRAG MIDI works exactly as it does everywhere else, and that is the point of the plug-in.
Two things Pro Tools does not get. FOLLOW is greyed out there: it listens on a sidechain, and declaring one stops Pro Tools listing the plug-in at all, so we took it out rather than ship something that cannot appear. And REHEAT MIDI DRIVER is not available, because Pro Tools has no slot for a MIDI plug-in the way Logic has its MIDI FX slot. Use DRAG MIDI instead.
Not there in Pro Tools? It only scans plug-ins when it launches, so quit it fully with Cmd Q and reopen. That is nearly always it.