PierM

You could grab a cheap Headphone amp (20 bucks for the Behringer HA400), and plug the RC500 line output to it, and headphones to the headphones out. This is just pushing the line level to headphone level. Won't sound pristine, but it should work just fine. You'll also need a Y cable with two TS jacks for the RC500 output going into a TRS jack for the Headphone amp. (Guitar----->HX Stomp----->RC500----->HeadphoneAMP----->Headphones)

I use PCs since the day they released lol. Please dont teach me how to use them...XD Never used their IRs. I use them as FRFR, and know every single aspect of them. The blanket is there, but as I said, as soon you are used to it, it will be fine. In fact I still use them. Also, blanket, the way I meant, means there is lack of clarity, Im not talking about highs or brightness. So there is not tips and tricks you can do to solve a clarity issue. Anyway, they are fine. Opinions. ;)

Powercabs are fine, but whatever setup you are using, they suffer the "blanket over the speaker" sound. Again, as soon your ears are used to that sound, you are probably gonna be fine with them...but if you jump from other systems, like studio monitors, or Catalyst, or other and better solutions, you really hear that boomy and muffled output, especially if they are placed on the floor. Even my old FH1500 sounds better than the two PC+, but the thing is heavy as a truck, so I can only use it at home.

Yes I had this same problem on both helix rack control and helix floor. Never had this issue using the tap button on the rack front, neither when using remote footswitches and/or midi commands. Also my HX Stomp doesn't suffer the issue, but it feels it's using different FS. When I investigated the issue on my boards, I've found that sometimes the footswitch was getting two taps in a single FS press/release cycle. So sometimes tapping 60 was resulting in ~120, or even more. Sometimes was like getting a tap when pressing, then another tap when releasing. Sometimes was just an instant double tap, resulting in a full throttle BMP... Sometimes even quitting the tuner, was double tapping. That was probably a malfunction on the little switch that sits under the mechanical footswitch (Helix does use a tactile switch being pressed by a FS mechanical assembly, which is the one you kick). Not saying you have the same problem that I encountered, but yeah, I had this. Didn't found any definitive solution, as it depends on a multitude of factors, such angle of pressure, applied force, speed etc... Probably, in my case at least, the solution would have been to replace the tactile switch, but for me didn't worth it the effort.

Not a valid statistic, but I've (had) 3 Helix (floor, rack and Stomp), along almost 8 years, and only get once on the stomp. I'm a OCD guy, so I had a full backup to restore. Was indeed random, and not a user error. They are computers, and as computers they go fubar every now and then...

The test I did between zoia and stomp was via two WIDI master, and really worked. I even tried with no subdivisions (1/1), and tremolo was pulsing in sync with blue flashing. Also tried setting a delay in the zoia clocked togheter with the Stomp tremolo, and they were locked properly. Of course this wont help you much as your setup is different, but imho that is how it should behave. As for the jitter, I remember getting problems with some hardware that I tried to use as clock source (via midi cable this time), and that Helix didnt manage to follow...but in that case I remember the blue flashing was clearly off and erratic (sometimes even flashing red in between blue, which means disconnections from the clock).

I just tried on a HX Stomp, tiding clock from a Zoia to the Stomp (tried with tremolo speed set to 1/4 and 1/8) and seems working as expected. I can input a tempo in the Zoia (via tap or CV) and Stomp is following. Depending on the clock source, I've experienced some serious jitter with MIDI clock that Helix in general doesn't really like, maybe that's the problem.

You never stop learning. :P

What is a STP preset?

Just go back to the store and pick another one. This is not something you can fix yourself, without voiding the warranty and stressing yourself for no reason. :)

Description gave me an headache. These things, without a sound sample of the problem and a very specific documentation on power sources, routing, devices involved and settings, are just opening a door for an infinite list of assumptions, guessing or different interpretations of that "tremolo" effect. Never had/heard something similar tho.

Point is, if you DIY, you will void the warranty for any future/further possible assistance. I would still let do the job to a Line6 licensed center, like Thomann, and keep the warranty alive as much as you can. ;)

Well, it depends on the frequency spectrum you are generating with any of those sims (**), and the dB at the mix output that it's hitting the speakers. There is nothing, native side (as any other VST), that it's changing when you change speakers. (**) that's A LOT of variables between the two different VST code and presets

When you change the sound pressure, without compensate the volume delta, your ears will perceive the tone differently. Biggr the delta, the wider the difference. It's the Fletcher Munson curve. At low listening volumes – mid range frequencies sound more prominent, while the low and high frequency ranges seem to fall into the background. At high listening volumes – the lows and highs sound more prominent, while the mid range seems comparatively softer. Yet in reality, the overall tonal balance of the sound remains the same, no matter what the listening volume.

The Airturn Duo 200 has BT midi (if it can be programmed), so you could grab a CME WIDI Master for the Helix, and go wireless with the pedal you are used to. Anyway, plenty of options if you go Midi instead exp. (and you don't have to wait for something that probably will never be implemented)

Ah ok. Yes, Helix has a full bidirectional MIDI and Midi Clock, over USB.

Could you elaborate a bit more? Hard to understand what you are asking for...

None of the PCs has slots to plug the casters. I guess you could easily mount something like these instead of the rubber feets, but then you'd probably lose the built in tilt feature;

I believe it's a mix of both, pot value much higher than required, and the way the HX Stomp is sensing control voltage from that TRS, instead the expected TS. That EXP on the back is actually two TS ports (one feeding back to sleeve, and the other to the ring), not a single TRS pedal port. Not even sure how's possible you get it working without the 0/100/0 issue, but yeah, isnt really a ideal setup. Anyway, your pedal has nothing wrong. Is L6 that went completely out of standards with exp pedals. You could easily mod it with a different pot and wiring TS, but this would make it not compatible with other pedals.

Weird question, as it's clearly visible in the official shots... but yeah, it has a small volute. Something like a mid 70 Gibson.

I do often use a HXStomp with a Zoia in the FXLoop, and that in the Fxloop of a helix rack. Im very sensible to latency, but I cant feel anything wrong with that setup, despite numbers on paper. Sometimes it's just overthinking. :)

Unfortunately there is not a dedicated erase command for the Looper. If you loop has been stopped, as soon as you press rec again, previous one is gone and new is being recorded. It's a bummer, but it is what it is. Never tried that myself as I don't use that looper, but maybe you can program a sequence of CCs to simulate a Stop/Rec/Play/Stop. Not sure if this make sense tho, since - as said above - as soon as you press record after a loop stop, it's starting with a new loop anyway. As for the output volume of the loop, you could simply assign the Exp pedal to control the Playback parameter of the looper block. There is not a reserved CC for that, so you have to assign it within the block. I guess you could then save that looper block with the exp assignment as fav.

The stomp wont accept a TRS exp pedal without doing weird things. The TRS it's expecting two separate circuits, that you can set in the globals as exp pedals or footswitches. The dedicated Mission SP1-L6H has a TRS cable because the pedal has a toe footswitch, so its two circuits. Just wondering how are you actually connecting that TRS from the pedal, to the TRS on the Stomp...could be you are hitting 100% way before the end of the pot travel.

Nope.

I do use a USB fixed cable than runs underneath my pedalboard, which has an angled USB B plug to prevent kicking damages. The other side of the cable (USB A) does pop from the other side of the board, ready to be used when needed (when not in use it's just velcroed on the side). Means you plug it once and forget.