In our company studio we are currently using two vMix instances, one (STUDIO1) as the primary production instance (for the primary voice language) and a second one (STUDIO2) for producing the translator voice-over variant. We bridge the output between STUDIO1 and STUDIO2 with a simple NDI connection and this works just fine.

Although the primary vMix instance STUDIO1, where we do all the mixing, is a fast PC, we now came to its limit due to 170 inputs, a rather elaborated greenscreen and virtual PTZ base setup with 4 4K-cams and 7 virtual angles per camera, many embedded VST audio plugins on 8 mics, etc. Especially, because in order to get good looking Full-HD virtual/zoomed close-ups from the 4K camera inputs, I would have to drive vMix on STUDIO1 in 4K mode. This is impossible from the load, because the machine is already at the limit in HD mode. So, I would like to offload especially the camera and audio ingest to a third vMix instance (STUDIO0) and keep just the scene mixing on STUDIO1, etc. The STUDIO0 optimally runs in 4K mode and delivers the virtual HD camera results to STUDIO1.

But, what would be the best way to bridge the two vMix instances STUDIO0 and STUDIO1?

For the offloading the audio ingest, I can simply move all VST plugins from vMix at STUDIO1 to a VST host like Cantabile on STUDIO0 and use a bridging solution like BlueCat's Connector to send the filtered audio streams of the 8 mics from STUDIO0 into vMix on STUDIO1. This is easy.

But what is the best solution for the offloading our HD-sized 4x7=28 virtual PTZ based camera inputs from the 4K-resolution vMix on STUDIO0 to the HD-resolution vMix on STUDIO1? 28 NDI streams and then do the selection on STUDIO1? Or just 2 NDI streams, one for the stream in Program on STUDIO1 and one for the Preview in STUDIO1 and then do the selection on STUDIO0? The first approach seems to be too network heavy but allows flexible mixing, the second approach is network-friendly but complicates the mixing (because we usually have scene inputs with embedded camera inputs, etc).

Can anybody give a recommendation for a scenario like our one?

I've now crafted a VB.Net vMix script to realize such a mentioned "tunnel N inputs over just 2 NDI inputs". You can find the script under https://github.com/rse/v...b/master/input-bridge.vb and the documentation under https://github.com/rse/v.../master/input-bridge.md.

Yes, I know about Dante, of course. Its pro is that it allows flexible routing, although in my particular vMix bridging scenario I do not need this routing feature. Hence, I thought it could be better to bridge the 8 mics in a hard-coded fashion just with BlueCat's Connector VST plugin. Beside routing, do you see another benefit of using Dante Via instead of BlueCat's Connector? Especially, for offloading the VST plugins I plan to use Cantabile (or Live Professor) as the VST host. It has to attach via ASIO to the mics. Dante Via is also an ASIO device, right? But as I cannot use two ASIO devices (and also no additional WDM devices) at the same time in a VST host like Cantabile (or Live Professor), how would you send the results out of Cantabile via Dante Via? Because that the reason for my idea with BlueCat's Connector: it's a VST plugin itself, so it does not interfere with the ASIO device the mics are on (Focusrite Scarlett 18i20 in my case).

i think ASIO4ALL can aggregate multiple devices as one ASIO driver however if the bluecat option is already working not sure you would see any benefit..