Line 6 Helix Stadium Pre-Launch Discussion

[Orvillain]

I wasnt sure if it was radio silence or some version of "we're triple checking everything"

They've not said anything, and honestly, there's only a handful of people talking about it. There aren't enough units in hands yet really to get a proper lay of the land. Preferring the sound of the legacy Panama is not the same as saying that the Agoura Panama has accuracy problems.

So my reading in this area constitutes basically a few toilet sittings, a bunch of ChatGPT interrogation, and some ResearchGate browsing while plopping.

Now from what I know of amp modelling, you've got your basic bullshit stateless waveshapers. That's what everyone was using in the early days of 2004-2008, say. Not much more than cascaded tanh functions. The tanh is a seriously useful function, and roughly can sound quite 'tube like' - if you remember any early amp simulator, it'll be doing variations on stacked tanh functions.

Then you started to get amp sims built on Hammer-Weinstein principles, where engineers and DSP developers realised that distortion in an amp circuit probably isn't stateless; or memoryless. That's when you get frequency dependent distortion, with linear components feeding into non-linear components, and back into linear. That's when amp sims start to actually kind of respond properly to palm-muting versus open chords. This is where the famous EQ > Distortion > EQ concept comes from; in a general sense. You read it on forums all the time, or a variation of it by people who have half a clue. This would've been Amplitube 2 era.

And loads of stuff has been done on that basis, and complicated further by just chucking more shit into the signal path.

Then a clever cloggs comes along and goes, well no.. what if we actually model tube physics. Don't have the computation for it? Let's generalise it. That'll be your Axe FX II, your initial Softube plugins probably, possibly even Amplitube 3. Who knows. Hard to tell. But around that era there was a serious step up in quality for amp sims.

Then after that, circuit-level modelling came. Wave digital filters, modified nodal analysis, applying Newton–Raphson solvers to nonlinear equations to essentially recreate diodes and other components. From all of this, you can build complex triode or pentode dynamic models, build real-time dynamic power supply emulation, and proper feedback loops; which is essential for good NFB. That's your Axe FX III, in essence.

Then from about 2015 onwards, it's been machine learning approaches. Using WaveNet style neural networks to compute convolutional models that learn nonlinear systems. They really got popularized in the last decade or so.

Now it is difficult for me to state where Helix lies in all of this. But my guess would be somewhere between generalised modelling approaches, and full circuit level modelling. I'm sure some of OG Helix was properly circuit modelled. I reckon quite a lot of it was more generalised due to computing power and tech stack implications.

Sooooo.. my whole line of argument being... if you prefer OG Panama ... it is entirely possible that your ears PREFER the more inaccurate model. To you it might be better. But it doesn't really mean that the new Agoura models are less accurate. I'm willing to bet that they are in fact more accurate and that there isn't any problem whatsoever.

 

[Orvillain]

BTW - at FXpansion we were doing circuit modelling and component modelling in synths back in 2008 with the first release of DCAM Synth Squad.

Now THAT was a fucking set of plugins!!

 

[Foxmeister]

Well, my UK unit has arrived!

Couldn't get it to connect to any of my WiFi networks, so I hotspotted from my phone.

After that connected, I was able to connect to my proper WiFi.

 

[molul]

Every pic is more beautiful than the previous one. Congrats everyone.

I love the elevation difference between the two footswitches rows. Big win

 

[Gary_W]

They've not said anything, and honestly, there's only a handful of people talking about it. There aren't enough units in hands yet really to get a proper lay of the land. Preferring the sound of the legacy Panama is not the same as saying that the Agoura Panama has accuracy problems.

So my reading in this area constitutes basically a few toilet sittings, a bunch of ChatGPT interrogation, and some ResearchGate browsing while plopping.

Now from what I know of amp modelling, you've got your basic bullshit stateless waveshapers. That's what everyone was using in the early days of 2004-2008, say. Not much more than cascaded tanh functions. The tanh is a seriously useful function, and roughly can sound quite 'tube like' - if you remember any early amp simulator, it'll be doing variations on stacked tanh functions.

Then you started to get amp sims built on Hammer-Weinstein principles, where engineers and DSP developers realised that distortion in an amp circuit probably isn't stateless; or memoryless. That's when you get frequency dependent distortion, with linear components feeding into non-linear components, and back into linear. That's when amp sims start to actually kind of respond properly to palm-muting versus open chords. This is where the famous EQ > Distortion > EQ concept comes from; in a general sense. You read it on forums all the time, or a variation of it by people who have half a clue. This would've been Amplitube 2 era.

And loads of stuff has been done on that basis, and complicated further by just chucking more shit into the signal path.

Then a clever cloggs comes along and goes, well no.. what if we actually model tube physics. Don't have the computation for it? Let's generalise it. That'll be your Axe FX II, your initial Softube plugins probably, possibly even Amplitube 3. Who knows. Hard to tell. But around that era there was a serious step up in quality for amp sims.

Then after that, circuit-level modelling came. Wave digital filters, modified nodal analysis, applying Newton–Raphson solvers to nonlinear equations to essentially recreate diodes and other components. From all of this, you can build complex triode or pentode dynamic models, build real-time dynamic power supply emulation, and proper feedback loops; which is essential for good NFB. That's your Axe FX III, in essence.

Then from about 2015 onwards, it's been machine learning approaches. Using WaveNet style neural networks to compute convolutional models that learn nonlinear systems. They really got popularized in the last decade or so.

Now it is difficult for me to state where Helix lies in all of this. But my guess would be somewhere between generalised modelling approaches, and full circuit level modelling. I'm sure some of OG Helix was properly circuit modelled. I reckon quite a lot of it was more generalised due to computing power and tech stack implications.

Sooooo.. my whole line of argument being... if you prefer OG Panama ... it is entirely possible that your ears PREFER the more inaccurate model. To you it might be better. But it doesn't really mean that the new Agoura models are less accurate. I'm willing to bet that they are in fact more accurate and that there isn't any problem whatsoever.

An interesting read.

I’m not sure how they’re doing it either and I haven’t received mine yet (under 2 hours, not that I’m counting :) ). From my current perspective of ‘not actually knowing as I haven’t heard it yet’ what would seem logical to me is that
1. On paper, it will be more accurate - Agoura is using components, previous version modelled chunks of circuits. Happy to be put straight there. If this is the case, it would explain why they sound different
2. In some cases they may have used a different amp vs before which may have different characteristics vs the old one
3. Does the hype knob (whose job it is to dispense with accuracy and make it sound more like people think it should sound) get you closer to the original helix amp model? They’ve basically sold hype as ‘sometimes these things don’t sound anywhere near as nice in real life as you’d like to imagine. Hype gets you away from aspects of reality that you might find sonically unpleasant’

 

[Fireproof]

Well I was supposed to be home yesterday at 3pm where my Stadium is waiting for me on my desk in my home office (wife received it for me Wed).

But due to weather and flight cancellations- I won’t be getting home until tonight. And then we have evening plans.

So I guess I won’t get to play with it until tomorrow. So close though…. LOL.

 

[paisleywookiee]

They've not said anything, and honestly, there's only a handful of people talking about it. There aren't enough units in hands yet really to get a proper lay of the land. Preferring the sound of the legacy Panama is not the same as saying that the Agoura Panama has accuracy problems.

How many people saying they think Agoura isn't as accurate have actually played it?

 

[ian_dissonance]

How many people saying they think Agoura isn't as accurate have actually played it?

It’s the same people that play a half stack wide open and claim to hear aliasing on YouTube.

 

[Digital Igloo]

How many people saying they think Agoura isn't as accurate have actually played it?

I'd guess very few. The bigger question is how many people have a vested interest in Agoura not being as accurate?

 

[Danelectro]

Dammit. I bought my Stadium from a vendor who I work with and the ship time is not until the 28th. I received a nice discount, so in the end it will be worth it, however seeing all these posts about people receiving theirs is driving me nuts.

 

[Digital Igloo]

I wasnt sure if it was radio silence or some version of "we're triple checking everything"

I wake up early this morning, make sure nothing's missing from my bags, check the usual sites (nothing about the Panama), get to LAX, board the plane, take off, log into Wi-Fi, and the time between this morning and now is "radio silence"?

Man, I knew LAX traffic was bad, but dang. Did it really take multiple days to get there?

Regardless, I think the 5153 we modeled for Agoura might've been different from the one we modeled for HX. Ping Ben on Facebook if you'd like confirmation; I'm grabbing an in-flight bloody mary.

 

[Orvillain]

I'm grabbing an in-flight bloody mary.

I'm there in spirit with a Guinness!

 

[paisleywookiee]

I'd guess very few. The bigger question is how many people have a vested interest in Agoura not being as accurate?

That would be disappointing, though I guess not surprising.

 

[[Nathan]]

I wake up early this morning, make sure nothing's missing from my bags, check the usual sites (nothing about the Panama), get to LAX, board the plane, take off, log into Wi-Fi, and the time between this morning and now is "radio silence"?

Man, I knew LAX traffic was bad, but dang. Did it really take multiple days to get there?

Regardless, I think the 5153 we modeled for Agoura might've been different from the one we modeled for HX. Ping Ben on Facebook if you'd like confirmation; I'm grabbing an in-flight bloody mary.

I didn’t mean that wording in an accusatory tone, I was just asking if it had been acknowledged and if it raised some eyebrows at HQ or if there were simpler explanations like “we used different amps for the modelling”

The topic hasn’t swayed me at all, I’ll still be grabbing a stadium and following along for the life of the unit.

 

[benadrian]

Hey humans!
I'm 99% certain that the same 5150iii head was used as a reference for both the HX and Agoura models. I was not the Sound Design engineer that did the modeling for either HX or Agoura models, so I have not had my hands inside this amp.

Cheers!
Ben

 

[GLiDE-BPM]

Hey humans!
I'm 99% certain that the same 5150iii head was used as a reference for both the HX and Agoura models. I was not the Sound Design engineer that did the modeling for either HX or Agoura models, so I have not had my hands inside this amp.

Cheers!
Ben

Now a proud Stadium owner!

Too bad I can't sound test it until the wife and I get home from eating dinner!

 

[GTR37]

Hey humans!
I'm 99% certain that the same 5150iii head was used as a reference for both the HX and Agoura models. I was not the Sound Design engineer that did the modeling for either HX or Agoura models, so I have not had my hands inside this amp.

Cheers!
Ben

Hey Ben ,
Just out of curiosity , I know you guys have the actual original designer Howard at Line6 , did he work or consult on that model at all ?

 

[banned]

Hi @benadrian, can you tell us how you measure and quantify 'feel'. There's definitely an improvement on that front from some of the comments and videos but how are you guys ensuring that it's objectively better?

What are some of the technical metrics that you use? Classical metrics like Rise time, overshoot etc....power supply sag, recovery etc.? Or is it more subjective testing from your guitar players?

Anything you can share?

 

[EOengineer]

I wasnt sure if it was radio silence or some version of "we're triple checking everything"

IIRC DI has alluded to pretty extensive testing and comparison in the agoura development process. That’s not to say mistakes don’t happen, we’re all human, but @James Freeman would need to be here with some charts and a presentation.

I’m hoping to spend more time with the high gain stuff this weekend so I can dig in. The little I’ve played sounds and feels fantastic.

 

[benadrian]

Hey Ben ,
Just out of curiosity , I know you guys have the actual original designer Howard at Line6 , did he work or consult on that model at all ?

I believe that Howards was brought in when we had some "why is it like this?" questions. I don't know the details in this specific case.

Hi @benadrian, can you tell us how you measure and quantify 'feel'. There's definitely an improvement on that front from some of the comments and videos but how are you guys ensuring that it's objectively better?

What are some of the technical metrics that you use? Classical metrics like Rise time, overshoot etc....power supply sag, recovery etc.? Or is it more subjective testing from your guitar players?

Anything you can share?

To start, I haven't figured out what I can say publicly about the process and what we have to keep to ourselves. So, unfortunately, I can't get too into the details yet. However, someone earlier commented about component modeling vs. the HX "sub circuit" modeling.

In HX, we have DSP elements that can change the sound; filters, gain, tube simulators, power supply sag, etc. All of these start at a neutral point, like the DSP is zeroed out. When making HX models, we measure the change of sound in a small bit of analog circuit, and then we set the DSP elements to make those same changes. All of the sonic changes have to be matched manually or semi-manually. Anything that is "feel" related comes along with matching the measurements. If it's not quite there, we can tune it manually. It's a long process, but everyone liked the results. In addition, this type of modeling easily allows original models to be made.

Agoura modeling is different. Like I said, I can't get into it, but it doesn't start with DSP set at a zero point that we then manually configure.

I know this might still leave you in the dark. As an egalitarian, DIY punk rocker, I want to share everything and live in an open source world. I'd love to talk about the fine details in depth. It's so new, so specific, and took a lot of R&D to develop. I'm sure we will have talking points and informational video in the mid-length future. Right now, we're all working on 1.2, 1.3, and beyond.

Thanks!
Ben