vali2

I’ve owned a Vali 2 with a Genelex Gold Lion for just over a year now. I just picked up the Magni 3. Normally I run my FIIO X3 II direct into my Vali then to my HIFIMAN HE-400i’s. What would be the easiest and best setup to A/B these two amps? Would it be kosher to use an 1/8 male end that goes...