Adventures in DIY: A Virtual Machine for Virtual Instruments

Create a virtual machine for your virtual instruments
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At my job, everyone runs both Mac OS and Windows, and many of us run both at once on the same computer. The secret is Parallels (; $79), a Mac app that runs multiple operating systems in virtual machines. With a three-finger swipe on my Mac’s trackpad, I can teleport from Cupertino to Redmond, even pasting data between programs.

That got me thinking: What if I could run simultaneous music apps on each virtual machine? That would open the world of Windows VSTs to my Mac-based DAW.

Fig. 1. When you connect a USB device, Parallels asks which virtual machine should use it.

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The secret to that turned out to be my iConnectAudio2+ interface (; $199). The dual USB ports on iConnectivity interfaces let you connect two computers at once (or one computer and one iOS device), streaming audio and MIDI between them. So, I plugged a USB cable into one port on my Mac and told Parallels to connect it to Windows, then plugged a second cable into the other port and told Parallels to connect it to the Mac (see Figure 1). To the interface, the one computer now looked like two.

One of the advantages of Windows for musicians is the vast landscape of unique VST soft synths at sites such as I grabbed SQ8L, which emulates the Ensoniq SQ80, the successor to the classic ESQ-1 wavetable synth (; free). I then loaded that into VSTHost (; free). At first, there was a massive lag when playing the synth from my MIDI controller, but a visit to VSTHost’s Devices menu to set up iConnectivity’s ASIO driver fixed that. I selected Low Latency mode and reduced the buffer size until I heard crackling, then backed it off a notch.

Fig. 2. Playing a Windows VST from the Mac via an iConnectAudio2+ interface.

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Configuring iConnectivity’s elaborate routing software, iConfig, took more experimentation. I routed USB 1 inputs 1 and 2 (Windows) to channels 1 and 2 of the interface’s analog mixer, and USB 2 inputs 1 and 2 (Mac) to channels 3 and 4. Then I routed the mixer’s output to the headphone jack. On the MIDI screen, I played with combinations of USB and DIN I/O until I was able to play and hear everything from Ableton Live on the Mac side (Figure 2). See my video at for a walkthrough.

I did experience some latency on my elderly MacBook Air, but opening the wild world of Windows VSTs in a compact setup made it worth the tradeoff. What unexpected instruments are you connecting? Send details to; I’ll feature the best ideas in a future column.