Helix Amp Models Producing DC

[Boudoir Guitar]

Hey, at least you know how to colored font where those of us in dark mode can still read the post

Always.Leave.One.Letter.Black. I trust y'all can play Wheel of Fortune with context clues.

 

[JiveTurkey]

Always.Leave.One.Letter.Black. I trust y'all can play Wheel of Fortune with context clues.

I'm going to need a crunch clip with no IR to know what you are referring to.

 

[Boudoir Guitar]

I'm going to need a crunch clip with no IR to know what you are referring to.

All Tone Knobs On Zero sounds phooked, bruh.

 

[MirrorProfiles]

And one more for the benefit of Jay and absolutely no one else:

 

[James Freeman]

Calm your tits Scrooge.

 

[KingsXJJ]

Hey, at least you know how to colored font where those of us in dark mode can still read the post

Dark mode always.

 

[jay mitchell]

You can look at the waveform and see significant DC offset. And DC detection algorithms show DC offset.

Here is a print of the signal with no audio at input, and me zooming in on the waveform. Is there offset or is it symmetrical?

There's offset. In the absence of either vertical or horizontal scales, the level and duration are unknown.

Here is a DC Offset meter from Izotope on the above for the avoidance of doubt.

Again, no vertical scale.

In the OP, you said "DC offset – visible as energy at the far left of the FFT (essentially 0Hz)." That does not establish the presence of DC. The additional information you provided in response to me does establish the presence of some DC level in the digital signal.

You also said later "Haven’t tried via USB or SPDIF but I did test on HX stomps analog outputs and it’s present there, so I’m pretty certain it’s across the entire line." IOW, you used a test that doesn't correctly identify DC. Otherwise, you would not have mistakenly decided that there is DC on the analog outputs.

As it turns out, that DC does not make it through the analog outputs.

I think there is reasonable evidence to suggest there is DC unintentionally being created from the amp modelling.

Evidence that you only bothered to provide when your original "evidence" turned out to be incorrect.

We can have the electronics class later if you like.

Might not be a bad idea. Just sayin'....

 

[Boudoir Guitar]

View attachment 46993

Calm your tits Scrooge.

Maybe don't delete, but would probably be a MILLLION times more productive with a lot less bickering if it was "Hey, I saw this weird thing that doesn't seem right to me. Thoughts?" Rather than "I Assert your Product is Broken and I Have Graphs" in a forum where, at best, a single digit percentage of the folks can properly interpret the associated graphs.

 

[KingsXJJ]

I’d like to sign up for the class. I’m always up for learning new stuff.

 

[Boudoir Guitar]

I’d like to sign up for the class. I’m always up for learning new stuff.

View attachment 46996

Homepage | Texas ECE - Electrical & Computer Engineering at UT Austin

www.ece.utexas.edu

Last college level physical science class I took did not give credit for answers in Star Trek Meme Format, though.

 

[JiveTurkey]

Maybe don't delete, but would probably be a MILLLION times more productive with a lot less bickering if it was "Hey, I saw this weird thing that doesn't seem right to me. Thoughts?" Rather than "I Assert your Product is Broken and I Have Graphs" in a forum where, at best, a single digit percentage of the folks can properly interpret the associated graphs.

Insert House of Learned Doctors gif here

 

[KingsXJJ]

Homepage | Texas ECE - Electrical & Computer Engineering at UT Austin

www.ece.utexas.edu

Last college level physical science class I took did not give credit for answers in Star Trek Meme Format, though.

I heard the new Prof is in to it.

 

[jay mitchell]

Maybe don't delete, but would probably be a MILLLION times more productive with a lot less bickering if it was "Hey, I saw this weird thing that doesn't seem right to me. Thoughts?" Rather than "I Assert your Product is Broken and I Have Graphs"

That sort of stuff isn't new by any means. Clark Kent, aka ML Sound Labs, famously did that on the FAS forum quite a few years ago. As it now turns out, there really is some DC offset produced by the amp block of some Helix models. However, the test that MP shared to demonstrate that in the OP fails to do so. He had to resort to other tests, and only in response to having his errors pointed out to him. You're welcome, MP.

 

[KingsXJJ]

If this discovery pans out to be valid, I wonder if some ears/brains are more sensitive to it than others.

It might explain why some prefer different products.

 

[JiveTurkey]

If this discovery pans out to be valid, I wonder if some ears/brains are more sensitive to it than others.

It might explain why some prefer different products.

 

[James Freeman]

Maybe don't delete, but would probably be a MILLLION times more productive with a lot less bickering if it was "Hey, I saw this weird thing that doesn't seem right to me. Thoughts?" Rather than "I Assert your Product is Broken and I Have Graphs" in a forum where, at best, a single digit percentage of the folks can properly interpret the associated graphs.

Nah, I'm not here to entertain you, this is a bug report thread.
Digital Igloo wanted us to "BE BRUTAL", the least we can do is post a few graphs and tell them that this particular model sounds like fuzzy diarrhea.

 

[sashimi]

 

[Orvillain]

I repeat, do not - attempt to use spectral analysis to detect DC. It's possible to do so, but you really have to know what you're doing.

How do you use spectral analysis to detect DC?

 

[Boudoir Guitar]

That sort of stuff isn't new by any means. Clark Kent, aka ML Sound Labs, famously did that on the FAS forum quite a few years ago. As it now turns out, there really is some DC offset produced by the amp block of some Helix models. However, the test that MP shared to demonstrate that in the OP fails to do so. He had to resort to other tests, and only in response to having his errors pointed out to him. You're welcome, MP.

Yeah, I get that, and don't care how we got to that knowledge at this point with the thread being irredeemably messy without a massive group edit, but trying to understand what it means:

To my understanding, a DC offset would mean EVERYTHING was shifted, which...doesn't seem to me to matter to the accuracy of a digital model since we offset levels after-the-modeling-is-done at several points anyway?

 

[MirrorProfiles]

As it now turns out, there really is some DC offset produced by the amp block of some Helix models. However, the test that MP shared to demonstrate that in the OP fails to do so. He had to resort to other tests, and only in response to having his errors pointed out to him. You're welcome

There was clearly enough suggestion of DC that it warranted looking at. I felt it helpful to show that the noise caused by Ripple is different to the DC. The other tests are probably less helpful to the vast majority of musicians who visit this forum.

You’re the only person here who wanted a higher burden of proof, even though you can’t actually do anything more to look into it or fix it. The post has led to it actually getting looked at and hopefully fixed, if you think that is some kind of failure then I think you should re-examine what your priorities are and what kind of forum you’re spending time on. All I know (and really care about) is that there shouldn’t be DC, and that could have negative consequences on the behaviour of the modelling.

It’s a forum of musicians, not electrical engineers. Maybe consider that others may not post bugs in the same manner you might.