Question about the Crossover split - known issue?

[ZiggyZipgun]

Has anyone else noticed that certain effects or amps will combine the inputs and apply the crossover at the end of the individual signal paths?

 

My guitar is wired in stereo so I can route the neck and bridge pickups to different channels, and there lots of great tones to be found by combining the top end of one pickup with the low end of the other (I'm currently splitting at 875hz). This works well until I turn on any blocks in the individual paths, and then it's clear that both inputs are combined before being split into high and low channels. Some legacy effects don't cause this issue, but it seems that all non-legacy effects do.

 

Is this a known issue?

[Schmalle]

Try the stereo fx.

 

From the Stomp's manual:

Quote

Block Order and Stereo Imaging

 

The signal path in HX Stomp is stereo, carrying two channels of audio. When the device is fed a stereo input source (i.e., when discrete left and right signals are connected into the HX Stomp Left and Right input jacks), the source audio is processed discretely in stereo wherever stereo blocks are used within the path. Whenever a mono block is added within a path, both channels of audio are combined and sent out of the block as mono.

 

Most of the effects models in HX Stomp have both mono and stereo versions. A stereo block displays after its model name in the inspector. The stereo imaging—or how wide your tone appears with stereo speakers or headphones—is highly dependent on the type of blocks you add and in what order.

 

Legacy effects models vary in behavior, just as on the classic Line 6 effects from where these models originated.

• Legacy Distortion, Dynamics & Pitch/Synth effects are mono
• Legacy Modulation & Delay effects vary in that some are mono, some stereo, and some mono in/stereo out, where adjusting the effect’s Mix parameter can narrow the stereo image fed into them. It’s best to experiment with these effects and tweak the Mix parameter to achieve the desired stereo output results

• Legacy Filter and Reverb effects are stereo

 

[ZiggyZipgun]

I just tried it, and the stereo blocks do keep the high and low paths separate - but these blocks are placed in one path or the other, where you could not have a stereo signal when using the crossover.  When two inputs are used, it will send one to the high and one to the low, and that's what I'm trying to maintain.  The stereo distortion, modulation, and delays blocks in each path will help, but they will eat up more DSP, and since there are no stereo amp or preamp models, we're not able to create a proper bi-amping patch the way many bass rigs are built.

[Schmalle]

I'm not sure what you want. If you want to use effects on the lows and highs individually you can do that on their individual paths between the Crossover Split and the Mixer.

 

The Crossover Split does what it's supposed to do. Say you use it and then combine both paths into one again with the lows on one side (L or R) and the highs on the other (by panning in the mixer block). If you then use a mono block both sides (L and R) are summed to a mono signal at the input of that block. That's not an issue, that's expected behavior.

[datacommando]

On 7/6/2026 at 5:45 PM, ZiggyZipgun said:

since there are no stereo amp or preamp models, we're not able to create a proper bi-amping patch the way many bass rigs are built.

Hi,

 

Hmm… there is a guy here who would beg to differ on that point. Although, he uses a mono output bass into a Helix LT, it is only using the top 2 paths 1A & 1B, it should work on a single DSP Stomp, or Stomp XL.
 

Check this video from 11:49 - everything before that you would probably already know, regarding traditional bi-amping techniques.

 

Hope this helps/makes sense.

[ZiggyZipgun]

On 7/8/2026 at 12:05 AM, Schmalle said:

The Crossover Split does what it's supposed to do. Say you use it and then combine both paths into one again with the lows on one side (L or R) and the highs on the other (by panning in the mixer block). If you then use a mono block both sides (L and R) are summed to a mono signal at the input of that block. That's not an issue, that's expected behavior.

Certainly any mono block placed after the Mixer will combine both signals.  But when splitting two inputs with the crossover, you have to set the Mixer panning to hard left and right to keep the inputs separated, and placing any mono block (and some stereo ones) in Path A or B (before the Mixer) will automatically combine both inputs before the crossover.  

 

On 7/8/2026 at 4:43 AM, datacommando said:

Hmm… there is a guy here who would beg to differ on that point. Although, he uses a mono output bass into a Helix LT, it is only using the top 2 paths 1A & 1B, it should work on a single DSP Stomp, or Stomp XL.

Yeah, not an issue with one input.  And not a issue with the Y-split, sending two inputs to separate amps.  But using one pickup for highs and one for lows gets tricky!

[Schmalle]

On 7/8/2026 at 7:50 PM, ZiggyZipgun said:

Certainly any mono block placed after the Mixer will combine both signals.  But when splitting two inputs with the crossover, you have to set the Mixer panning to hard left and right to keep the inputs separated, and placing any mono block (and some stereo ones) in Path A or B (before the Mixer) will automatically combine both inputs before the crossover. 

That is all expected behavior.

If you want to "create a proper bi-amping patch the way many bass rigs are built" nothing is stopping you from doing that after the split (usually a hard left-right panned Split Y, but a Crossover Split can also work - although it seems a bit radical). I mean you would set amps differently and probably choose different amps in a bi-amping situation anyways, wouldn't you? There are some very little DSP demanding amp sims like the Del Sol 300 if needed. https://benvesco.com/store/helix-dsp-allocations/

[datacommando]

On 7/8/2026 at 6:50 PM, ZiggyZipgun said:

Yeah, not an issue with one input.  And not a issue with the Y-split, sending two inputs to separate amps.  But using one pickup for highs and one for lows gets tricky!

Ah!
 

Originally I should have asked how you are actually physically connecting your neck and bridge pups to your Helix, HX Stomp, (or whatever - you didn’t mention). I’m guessing it’s a Stomp, which has a Left/Right stereo input option.

 

If you were using a Helix Floor this would be a lot easier - tools for the job.

 

Hope this helps/makes sense.