I googled this scenario and found a solution sort of in this forum. I have Sonar Artist and this is what I did. I installed loopMIDI virtual midi cable, setting up three ports; enabling these midi ports in Preferences > Midi Devices > Input and Output in Sonar. The midi track is set to midi channel 5 and output to loopMIIDI port 1. The two simple instrument tracks hosting the synths are set to input loopMIDI port 1 at midi channel 5. When I start play I hear nothing. Only when I turn on input echo on both instrument tracks there is sound but with latency due to how the Buffer Size in Driver Settings is set. When I choose to output the midi track to either instrument track, playback is normal. I'm trying to layer the sounds from the two synths using one midi track. What am I doing wrong? 

I don't know anything about loopMIDI virtual MIDI cable, but when I want a MIDI track to go to multipe synths, I just copy the MIDI track to another, and route each to it's own synth.

Slugbaby
I don't know anything about loopMIDI virtual MIDI cable, but when I want a MIDI track to go to multipe synths, I just copy the MIDI track to another, and route each to it's own synth.

^^^^^ This is the easy way, You can group solo and mute buttons for the tracks.
 
Rocky

DeBro
Only when I turn on input echo on both instrument tracks there is sound but with latency due to how the Buffer Size in Driver Settings is set.

I think you answered your own question right there. The issue is audio output latency due to the buffer size, and you need to lower the buffer. You'll want to get the reported output latency under 10-12ms for decent feel. With the Scarlett using ASIO driver mode, I would think 256 samples or less should get you there.

Thanks guys. I'll just clone the midi track, route each to it's own synth, and bounce to a single stereo audio track name Layered Synths. I don't mix with instruments up and running so as to free up CPU resources.

Perfect application for an aux track ...

BobF
Perfect application for an aux track ...

Unfortunately, Sonar Artist does not have aux tracks. Just curious though, BobF, how would you apply aux tracks in this scenario?