CheckMyMix started as a Mac app: load a mix, switch between nine listening profiles — phone, earbuds, laptop, Bluetooth speaker, car, TV — and hear how it translates without bouncing it nine times. Two things were missing. It did not run on Windows, and you had to leave your project to use it.
Version 1.0 for Windows fixes both. It is a free download at quantumaccordbg.com/checkmymix: one installer, about 5 MB, with two things inside.
Update, 5 October: version 1.0.1, and why some PCs refuse the installer
Fixed in 1.0.1. If the app was asked to open a song before the PC's audio device had started — or on a PC with no sound device at all — it said "Could not open" about a perfectly good WAV or MP3. It now opens the file and starts playing when the device is ready.
Checked the way a customer would. For this version the installer was run on a real Windows machine: the plugin landed in C:\Program Files\Common Files\VST3, a plugin host loaded it from there, the app opened a song passed to it and played it, and the uninstaller removed everything. That is one machine, not every PC.
If Windows will not let you run it. The installer is still not code-signed. On most PCs you get a blue "Windows protected your PC" box: click More info, then Run anyway. On a PC with Smart App Control switched on there is no Run anyway button at all — Windows refuses every unsigned program, and this version cannot be installed there. A signed version is the fix, and it is not out yet. The download page lists each message and what to do.
Plugin only. The download page now also offers the VST3 on its own as a zip, for people who do not want the app.
What the installer puts on your PC
The app. The same idea as on the Mac. Open a WAV or MP3 (the Open Mix button, drag it onto the window, or Open With in Explorer), press Space to play, and switch profiles while it plays. Match loudness, Bypass, the mono check, the live spectrum and the A/B loop ([ and ]) are all there.
A VST3 plugin. This is the part producers asked for. The installer places it in C:\Program Files\Common Files\VST3, which is where FL Studio, Ableton Live, Cubase, Reaper and Studio One look.
Using it in FL Studio
- Run the installer and leave both boxes ticked.
- In FL Studio, open Options → Manage plugins and click Find installed plugins.
- Open the Mixer, select the Master track, and add CheckMyMix in the last slot.
- Press play, and click through the profiles.
Inside a DAW there is no transport in the plugin — your project is the player. You get the nine profiles, Match loudness, Bypass, the mono check and the spectrum.
Take it off before you export. CheckMyMix is for checking a mix, not part of the sound. Bypass it or remove it before you render, or your master will sound like a phone speaker.
The plugin adds 256 samples of delay (about 5 ms at 48 kHz) and reports it to the DAW, so the host compensates. It is the same on every profile, Bypass included, so the timing never shifts when you switch.
Two things to know before you install
Windows will warn you. The installer is not code-signed yet, so the first time you run it Windows shows a blue "Windows protected your PC" box. Choose More info, then Run anyway. A signing certificate removes that warning; we have not bought one yet, and would rather say so than have you wonder.
It needs 64-bit Windows 10 or later, and a DAW that loads VST3. There is no old-style VST2 .dll: Steinberg no longer licenses that format to new developers. FL Studio 20 and later load VST3.
Does it sound the same as the Mac app?
Very nearly, and here is exactly how nearly.
The Mac app is built from Apple's own audio units — its EQ, its distortion, its dynamics processor. Those do not exist on Windows or inside a plugin, so the Windows version could not reuse them. It is a port: the same nine profiles with the same numbers, running through our own code.
A port can drift, so we did not trust it by ear. We measured the Mac app's real audio path — frequency response at 31 frequencies per profile, the compressor's curve and timing, the distortion's harmonics, how the two channels share one detector, pink-noise level — and then took the same measurements on the port. An automated test fails if any of about 1,275 numbers leaves its tolerance. Today the two agree within 0.35 dB on frequency response, within 0.1 dB on the compression curve, and within about a third of a decibel per profile on pink noise.
Measuring turned up things no documentation mentions. The app's compressor listens to the mono sum of left and right, so out-of-phase material slips past it; it looks 256 samples ahead; its distortion is a cubic curve into a soft clipper. The port reproduces all three, because the point is to match what you would hear on the Mac, quirks included.
One known difference: the Mac app's audio path rolls off sharply at the very top (20 kHz), even with no profile selected. The port does not copy that.
What has not been tested
This is a first release, and it is honest to say what stands behind it. The Windows build passes the measurement tests above on a Windows machine, and a standard plugin validator loads the VST3, opens its window, runs audio through it and saves and restores its settings without a failure. It has not yet been used across a range of real PCs, audio interfaces and DAWs. If it misbehaves on yours, write to support@quantumaccordbg.com with your Windows version, your DAW and what you saw.
As with the Mac app, the profiles are modelled, not measured from specific devices. They represent how each class of device behaves — small speakers lose bass, closely spaced speakers lose stereo, cheap amplifiers limit. Use them as a fast first check, then confirm on a real phone and a real car before release.
And the plugin on the Mac?
Built: an Audio Unit for Logic Pro and GarageBand, and a VST3 for FL Studio and other hosts, in one installer. It is waiting on Apple's notarisation, and we will not offer a Mac installer that macOS warns about. It will appear on the CheckMyMix page when that is done. The Mac app itself is unchanged and still there.