Wondering what’s the best/easiest way to connect the Model:Samples with a PA for stereo sound. Ideally, I’d want to use a Y-converter so it could just go into one DI box input?
Difficult to be sure without knowing whether the inputs on your DI box are mono or stereo, but yes - that should be simple enough.
Do you want to use the Y-cable to mix two outputs into one? Y-cables are only for splitting signals, not for mixing. The reason is that even with a dual mono signal (same signal on both sides), slight voltage fluctuations can cause problems. If you have larger differences between left and right (like with stereo signals) you really shouldn´t risk that.
What inputs does the PA have? Mono DI, stereo DI? For mono, you can just connect one output from Model:Samples and pan all tracks to that side (if you use the left output, pan all tracks to the left).