Peter, perhaps I'm not understanding what you're trying to do but it sounds like you want to use 3 or more VSTi synths on various tracks in BIAB at the same time. Is this right?

As far as I know, BIAB can only handle one VSTi at a time. Back in 2017, a former user, by the name of Paul Warren, created a bit of software that would allow BIAB to use more than one VSTi at the same time. It could even allow the use of a combination of VSTI's and multiple hard synths all at the same time on a track by track basis. Unfortunately, it was 32 bit only and Paul does not have the required software to convert this to 64 bit.

I had very good success in using his MidiRedirector but like I said it was 32 bit only and now I'm using the 64 bit version of BIAB these days.

If you would like to give his 32 bit application a try, you can download it for free here:

https://bandinabox.fandom.com/wiki/VSTi_MidiRedirector_v_1.xx

Jeff

Win11, Intel i7 7700K 4.2Ghz, 32Gb RAM, 2x1Tb HD, 500Gb NVMe, BIAB/RB 2025, MOTU 828MK3 audio, MOTU Midi Express, Yamaha Montage 7, DX7II, TX802, Motif XS Rack, Roland Fantom XR Rack, Oberheim Matrix 1000, VoiceLive3 Extreme, Kontakt 6, SampleTank 4.3