Help with impedance questions

[cmoore75]

I am planning to replace my HX One with an HX Effects and I’m trying to determine  how big of a deal the lack variable input impedance will be. I understand the impact on a fuzz at the front of the chain but I don’t understand if there is any impact to effects later in the chain. I’ve seen that several of the delays and choruses have lower impedances but I wouldn’t put them at the front. Is it safe to assume that any effects chain that has an effect with 1M impedance at the front will sound identical on Hx effects as on HX stomp?

 

Also, it seems like it is the interaction between the pickups and the HX device that matters, so if I have a drive pedal between my guitar and HX effects does that make the whole thing irrelevant?

 

Thanks in advance to anyone who can shed some light on these questions. 

[theElevators]

In the real pedal world, "Fuzz "tone sucking" (volume/treble loss) often results from impedance mismatches, particularly when vintage-style Fuzzes (like Fuzz Faces) are placed after buffered pedals or active pickups."  Also in the real world, the Fuzz pedal sucks tone whether it's on or off, they are not true-bypass.  

 

In your case, you have a digital emulation of any pedal you want.  HX One has capacity to run exactly one block.  Digital pedals in an analog signal chain do not have any "impedance" and tone-sucking behavior, because they are digital devices.  They can suck tone on their own though to an extent, but they will do it consistently regardless of what effect you are running.  Just because you are running Fuzz on your HX One, doesn't mean that it will magically recreate the physical properties of an analog Fuzz Face and affect other pedals. 

 

 

 

In the Helix world, they replicate the "tone sucking" behavior, if you have a virtual signal chain.  Helix recreates those nuances when you have more than one block in your preset.  But it does it weirdly: only the first block in the virtual chain affects how the rest of the chain sounds in terms of its virtual impedance, if you set the impedance setting on your preset to "auto".  So if you have a wah, followed by 10 Fuzz pedals -- no tone sucking.  But one bypassed Fuzz pedal followed by 10 wahs -- it will suck the tone.  However, you can override this behavior by dialing in an explicit impedance value of your entire preset, then it stops behaving like it would in the real world.

 

Regarding how to set the impedance on your HX device:  My advice is to just set it to auto.  Auto take the first block's impedance and uses that.  For most effects it's 1M ohm.  Changing the impedance to a specific value between HX presets is a very bad idea, since it results in loud pops when changing presets.  

 

(For the record, I don't have HX One, and cannot confirm what it does when you bypass your Fuzz block, you would need to test it out. )

 

 

I also recommend just using your ears.  Digital doesn't always behave like analog, and sometimes not at all.  Add a Fuzz in your HX One.  Bypass it in one preset, compare it with a blank preset.  

 

If you start messing around with impedance, it may introduce weird harshness and resonant frequencies.  The difference in sound is there, but not that significant, mostly just becoming unpleasant.

 

One more piece of info: as a Helix user, I want all my presets to sound consistent.  All my presets are based around the same 'core' sound.  So if I wanted to add a Fuzz solo in one of my presets, I need the core sound to remain unchanged.  If I added the Fuzz in the beginning of the chain, I know that it would affect my tone for the whole preset very slightly (not something I want).  Therefore, I can either change the impedance of the preset to be the same value as other presets (1M ohm), or make sure that the Fuzz is placed second in line after the wah pedal, which I know has the correct impedance of (1M ohm).  But I would never change the impedance setting between the presets, because of the horrible noise glitch that will happen when switching presets!

 

See my old video of me messing around with the impedance.  There are also lots of threads on this topic.  In summary, set it to "auto", and forget about it IMO :) 

 

 

 

 

 

[cmoore75]

I appreciate the response. Your explanation of how the impedance setting works is helpful. My main concern is that the HX effects doesn’t have the auto-impedance feature and is set to 1M. It seems like that will maybe only affect presets with a fuzz 1st in the chain. I’ve already tested that impact with my HX One by switching between auto and 1M. I’m thinking I could probably mostly match the sound of the fuzzes with an EQ if needed. Some of the other effects, like memory man delay, also lower the impedance when on auto but I’m not likely to run a preset with the delay 1st in the chain so I’m not sure that matters. I also tested switching between auto and 1M with a drive pedal between the guitar and HX One and that does seem to lessen the impact of lower impedance but doesn’t fully remove it. 

[kduck]

On 3/27/2026 at 11:45 AM, cmoore75 said:

so if I have a drive pedal between my guitar and HX effects does that make the whole thing irrelevant?

If the drive pedal is buffered (most are), then the impedance of any pedals after the drive is irrelevant.  Your guitar will only see the buffer impedance of the first pedal (typically 1M or higher).