michaelhun

Yep it works just fine. I have both the DSL100H and the DSL40C and the helix changes channels on both of them just fine using a standard instrument cable. Just make sure you select single tip when setting things up. In order for it to control reverb as well I think a different set up is needed, but I don't personally use the built in reverb.

Is your FX loop on? I know on my amp if I don't have the FX loop engaged then I wouldn't get any sound with the set up we both tried.

I only just recently got the Helix, and I don't have the amp you are referring to, but I tried this exact idea and had good success by simply running the Helix 1/4 mono out into FX return of my amp and guitar into Helix. That's it. You shouldn't need to plug anything into the front of the amp, at least I didn't need to. This allows you to use the preamps from the Helix, and the power amp of your amp to power your cabinet or whatever you're using. So in a sense the"amp" in this situation that you are plugging your guitar into is inside the helix. The "FX loop" in this situation consists of everything post preamp inside your Helix and your actual amp's power amp. The signal is then fed into your cabinet. This might not be technically correct but that's at least how I understand it, and it has worked for me so far. Do be aware that bypassing the preamp essentially makes all your master volume, channel volume and onboard eq settings on your Blackstar useless, so you will need to control volume from the Helix directly. I think. Take this for what it is, the experience of a helix newb. I'd argue that whatever set up you use, if it sounds good, then it is good. Hope this helps.