NetVST on MacOS Big Sur with Wineskin 2.9+

This post is by guest contributor Tom A.

NetVSTHost was tested to work properly with the exact combination of Wineskin and WS11WineCX20.0.4 (or WS11WineCX64Bit20.0.4).

  1. Download the NetVSTHost version of your choice (64- or 32bit, or 32bit for WinXP from here:
    • Execute this command from a terminal: sudo xattr -drs NetVSTHost.exe
  2. Google and download the (EXE) Windows installer of Visual Studio C++ 2010 SP1 Redistributable, 32 or 64bit according to your NetVSTHost version.
  3. Install Wineskin Winery (homepage:
    • If you have Homebrew, just use: brew install --no-quarantine gcenx/wine/unofficial-wineskin
    • Otherwise: download it directly from here: (link is from the readme)
    • This way, you will have to disable quarantine on it before running: sudo xattr -drs Wineskin.Winery.txz
    • Copy to Applications directory
  4. Download version of Wineskin wrapper:
    • Again, run sudo xattr -drs
    • Extract with MacOS Archive Utility to convert to an executable app
    • Copy to Applications directory
  5. Run Wineskin Winery
    • Click + symbol
    • Install Wine engine version WS11WineCX20.0.4 or WS11WineCX64Bit20.0.4 according to your NetVSTHost version (32 or 64bit)
    • Ensure wrapper is Wineskin- -- Do NOT update wrapper version.
  6. Click "Create New Blank Wrapper", name it "NetVSTHost", and click "OK". Patience, it will take a few moments.
  7. An app named will be created in Home/Applications/Wineskin. You will be prompted to open this location on Finder. Do so.
  8. Double click (or alternatively, right click and click "Show package contents" and open
    1. Click "Advanced".
    2. Go to the "Tools" tab.
      1. Open "Config Utility".
        1. In the "Applications" tab, at the bottom, choose OS version according to your NetVSTHost version:
        • 64bit version - Windows 10
        • 32bit version - Windows 7
        • 32bit for XP - Windows XP (duh)
        1. Go to the "Libraries" tab.
        • Open the dropdown "New override for library" and add the following: d3d9, d3d9_43, dxva2, x3daudio1_7, xaudio2_9, xinput1_4, xinput9_1_0 (as you add them, they will appear in the list below).
        • Click "Ok"
        • Wait until the "loading" symbol disappears.
      2. Click "Install Software"
      • Click "Choose Setup Executable"
      • Point to the Visual Studio C++ 2010 SP1 Redistributable installer EXE file.
      • Follow the installation wizard.
      • If prompted with "Warning! No executable found", simply click OK and ignore.
      • Click "Cancel".
    3. Go to the "Configuration" tab
    • Click "Browse" and point to the EXE file of the NetVSTHost version you downloaded in step 1.
      1. If the program freezes, fear not. Go back to the Wineskin Advanced dialog, "Tools" tab.
    • Click "Kill Wineskin Processes", at the bottom of the "Utilities" list in the center.
    • Click "Registry Editor (regedit)" on the left.
    • Navigate to HKCU\SOFTWARE\NetVSTHost\NetVSTHost\Settings
    • Right-click on the right hand side panel, add a new DWORD value, name it "Engine". Ensure its value is 0 (0x00000000).
    • Close regedit.
    • Wait for the "loading" symbol to disappear.
    • Click "Test Run", or close the Wineskin dialog, and simply run the created in step 7.
    • Note: It's essential to run NetVSTHost once before opening Regedit, otherwise the NetVSTHost registry keys won't be there!"
  9. Troubleshooting: in the Wineskin Advanced dialog, click "Set Screen Options"
    • Choose "Retina Mode". That might fix input errors in some machines

macOS Catalina: maybe not the end of 32-bit

Some time back I said macOS Catalina was likely the end of the line for 32-bit Windows code on the Mac. I'm happy to say there is still hope. The clever and diligent people at CodeWeavers have just released version 19 of CrossOver Mac product (a commercial implementation of WINE for the macOS), which can actually run 32-bit code in 64-bit processes, on a 64-bit-only operating system.

I am flabbergasted. My flabber hasn't been this gasted since Apple managed to port macOS from the Motorola 68000 series to PowerPC processors, without having to rewrite most of the code, by creating a fast 68K emulator out of whole cloth.

I can't wait to try out CrossOver Mac 19.

See this CodeWeavers blog post to learn more.

Using multiple NetVSTHost instances

It IS possible to run multiple instances of NetVSTHost on different ports. The problem (my fault) is that the GUI doesn't display which IP/port a given instance is using, so when you have several open at once, it's hard to keep track of which is which.

The last IP/port you set gets saved to the Registry as a convenience, but if you open a second NetVSTHost, its attempt to open the same port will fail, so you can just go ahead and set a different port number.

If you go back to the first NetVSTHost instance and select Devices->Network, it will show the updated values from the Registry, but the program won't attempt to use them unless you click OK. If you click Cancel, it keeps using whatever it was using before.

I'm sorry this is so confusing. I had a look at the code today, to see if I could add the current IP/port to the NetVSTHost window title (to help you keep track of which instance is which), but I didn't succeed. That code is old, very complex, and wasn't written by me. (Which is why I have never published it.)

Until I have time to create a newer alternative NetVST host program (or figure out how to display IP/port in the existing one), you will need to find your own ways to keep track of the settings for multiple NetVSTHost instances. For example, I suggest you create them one at a time, assign them increasing port numbers, e.g. 27016, 27017, etc., and lay out the windows in a corresponding order, so port numbers increase from left to right or top to bottom.

UNIFY: Commercial product with NetVST built-in

For nearly a year, I've been working on my first commercial music software product, called Unify. This may be of some interest to readers of this blog, because the "Pro" version of the product will have NetVST technology built-in.

This post isn't meant to be an advertisement. It's more of an explanation for why I haven't updated the NetVST software recently. Hopefully, I'll be able to get back to that after Unify is released by October of this year.

I'd like to assure everyone that NetVST will still be available, and will remain free. For many of you, NetVSTHost and the NetSynth/NetFilter plug-ins are all you need, and you should continue using them indefinitely.

A few of you might be interested in Unify's additional capabilities for creating composite sounds, and I invite you to have a look at the press release and associated YouTube videos (many more of which are coming from my colleague John Lehmkuhl of

macOS Catalina: the end of 32-bit VST support?

This past week, I received a flurry of emails from software vendors, advising Mac users to hold off updating to macOS Catalina, because it won't support 32-bit binaries at all.

Most significantly, one of these emails came from CodeWeavers, makers of CrossOver, an excellent commercial implementation of WINE--the same technology which powers NetVSTHost for Mac. They included a link to their own blog post which explains why this issue is so thorny.

The heart of it is this:

Most Windows applications our users run with CrossOver are 32-bit and CrossOver uses a 32-bit Mac executable, system frameworks, and libraries to run them. This will break with Catalina.

So, even if I were to repackage NetVSTHost for Mac using the most recent 64-bit version of WineBottler, the resulting 64-bit binary would run under Catalina, but would only be able to run 64-bit Windows VSTs. In my view, this undermines the most important use-case for NetVSTHost for Mac, so I see little point in pursuing it.

NetVSTHost for Mac was never much more than a convenient little hack--a way to run the 32-bit, Windows-based NetVSTHost.exe program on a Mac, without having to set up a full virtual machine (using e.g. VMWare Fusion, Parallels Desktop, or the Mac version of VirtualBox), or better yet, use an actual Windows PC.

I would advise anyone who has come to rely on NetVSTHost for Mac, and who anticipates upgrading to macOS Catalina at any time, to look into the two-system approach for which the NetVST Project was originally conceived. Details can be found on the NetVST Project wiki.

NetVST is now part of AudioKit

AudioKit is an open-source framework to facilitate audio/music app development on Apple platforms, including Macintosh OSX, iPhone and iPad. I was recently invited to join the AudioKit core team, and I'm focusing my effort on expanding the "core" parts of the framework to other platforms, including Windows and Linux.

To this end, I've created a new code repository on GitHub called AudioKitNet, where I'm exploring how plugin vendors can modify their existing plugins to allow the DSP work to be done on servers.

NetFilter/NetSynth now have custom GUIs

Originally, the NetSynth/NetFilter plugins didn't provide a custom GUI, so you were stuck with whatever generic GUI your DAW provided. This turned out to be very clumsy for entering IP addresses and port numbers.

As of the December 24, 2017 update, both the AU (Mac) and VST (Windows) plugins provide a simple GUI to specify the IP address and port number for the remote server (NetVSTHost instance).

The Windows GUI looks like this, and you enter a single string e.g., then hit Update.

Windows GUI

The Mac GUI is almost the same, but has separate input boxes for the four IP address numbers and the port number; otherwise, it works the same.

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