Line 6 Helix Stadium Talk

For those using your own IRs as part of your testing, since the Stadium defaults to using the matching cab SIC, is this causing the difference in sound?
That is currently the behavior. My tests have been careful to account for that but it is a factor that needs to be considered.
 
Honestly wouldn’t blame him. We may have turned the corner from inquisitive to just flat out insufferable. :rofl

DI's got pretty thick skin, and I don't think the endless scrutiny and poking would chase him away for good any more than it has me as a happy Stadium XL owner. He's got a higher viewpoint and gets way more input from just the jabronis around these parts.

And from that 50,000 ft. view, he's the product manager of a highly successful launch of two flagship hardware SKUs with lots of development muscle and cool things coming down the pike. I mean, our input (and incessant non-constructive criticism) matters to some degree, but he's got lots more on his plate.
 
Getting a little presumptious calling one isolated comparison (not done with Line 6's actual source amp) establishing it's "fact" that the modeling is inaccurate, no?
TBF, Im not the first one who's questioned the SLO. Several users have noticed it sounds different to what they expect. I'm not saying it's wrong, but I do think it's odd. It's not one amp either - there has been the 5150, the jubilee, the IIC+, the SLO. It just depends what is under the microscope in any given moment. Some things have been attributed down to a cab block/SIC bug. That makes sense for sure, and its good its fixed.
As for Line 6 putting out another in-house comparison between their actual amps and the current-gen modeling, I'd say that would settle about as much for the accuracy of Agoura modeling as the previous comparison did to settle the accuracy of HX modeling....
I think all companies who are proud of the accuracy of their modelling should do this. The whole reason I came back to Line 6 in the Helix generation was because I was impressed with how accurate the modelling was when compared to real amps. It required videos from @GuitarJon and Leon and a few others, mind. I can only think of a few examples that do this:



Just looking through the comments section and I think it all seems to rub off quite positively?

Line 6 would be mad to get involved on every tonal discussion and are understandably just looking from the distance. I know the concerns are being looked at. Regardless, if they just said "hey, the reason things are quite different before is because this time round we did _______ because _______" then everything will make perfect sense to me. In fact, I think comments like this in the past have been what's made users more in tune to the influence of impedance curves and input levels etc.

As it stands, the lack of information (as to why the models are different, and what if anything the user needs to do to address the differences) is just going to lead people to speculate.

its also wild to me that certain people think that pointing out unexpected differences are an attack or poking. It couldn't be further from it - I want to understand what's going on. If users understand the behaviours and quirks of software, they get better results - thats a win for all. I want things to be the best they can be, and it all leads to helping to achieve the best results.
 
I would certainly not say it is a fact that Agora is less accurate. It seems like there MAY be an issue with a FEW of the high gain models. Others seem to be quite good.

My experience with real amps tells me that an early SLO from the 80's was quite different from a late 90's version and both quite different from the new BAD version I tried a couple years ago. I have had three 1974-1975 Twin Reverbs all side by side in my workshop at one point and despite being made within the same 12 month window to the same circuit, they sounded quite different. Even after servicing them and converting them to AB763 BF circuits, there was enough component variation that they still sounded different piped through the same cab, more so each with their own speakers. There's a good chance they all sound different today then they did then, and in fact I know one does because I still have it and a few more resistors have drifted way out of spec and need replacing.

If you don't have the original amp in the same condition it was in when modeled you simply don't know too much about accuracy.
 

Semi relevant to the current discussion.
These points apply BROADLY to software or really any engineering facet. I cannot count how many conversations I have had with product teams I was partnered with in my development career that could not answer these questions. It's no surprise that the most successful projects I've been involved with had these well spelled out before we started getting into requirements and story maps.
 
Because I know at least a little bit about the DSP behind this, I can say some things for certain. If you oversmooth the nonlinear solver, you get high frequency rolloff. If you get a filter coefficient wrong, you can filter frequencies you didn't mean to. If you use a median filter to average out data, you can blur transient response.

So when I hear a particular characteristic, like a subdued high frequency region, I cannot help but wonder if one of these types of things are at play. That's just how I think about it.
tl;dr post-mortem:

1770915834450.png
 
If you don't have the original amp in the same condition it was in when modeled you simply don't know too much about accuracy.
This is exactly what one of my posts was alluding to. We would need to know if it was the same amp. If so, it would be profiled/measured much later in its life. was it serviced? was it even serviced before the first model was calculated/made?
If it's a different amp altogether then there is going to be variation, as well as my later SIC commentary.
 
This is exactly what one of my posts was alluding to. We would need to know if it was the same amp. If so, it would be profiled/measured much later in its life. was it serviced? was it even serviced before the first model was calculated/made?
If it's a different amp altogether then there is going to be variation, as well as my later SIC commentary.
I think "It's not the same amp" has merit but is also simultaneously Deflection 101. No matter what company/vendor is saying it.
 
I think "It's not the same amp" has merit but is also simultaneously Deflection 101. No matter what company/vendor is saying it.

Yep, impossible to know. Kinda like "the product you want is out of stock due to COVID". Maybe it was COVID, maybe incompetence, but impossible to tell from where we sit.
 
YOU'RE DOING IT WRONG!!! Watch my video to fix 40 years of development mistakes in 15 minutes with this one simple idea!
Honestly he’s pretty on par with what I’ve experienced in my career, though I’m in web and not audio software (YET).

This is exactly what one of my posts was alluding to. We would need to know if it was the same amp. If so, it would be profiled/measured much later in its life. was it serviced? was it even serviced before the first model was calculated/made?
If it's a different amp altogether then there is going to be variation, as well as my later SIC commentary.
Just my opinion, but I think you’re overstating the cumulative effect of aging and natural variation. An amp with the same circuit (so let’s say the same revision of a given amp) will drift a bit but generally I’ve found those differences to be pretty minor under a mic.

In reality I think a lot of folks have encountered vintage amps that are missing bright caps, have non stock replacement values, etc and that can easily get misinterpreted as the effect of amps drifting in sound over time.

Yes there can be differences, but not THAT big, like in my earlier 2C+ comparisons.
 
I would certainly not say it is a fact that Agora is less accurate. It seems like there MAY be an issue with a FEW of the high gain models. Others seem to be quite good.

My experience with real amps tells me that an early SLO from the 80's was quite different from a late 90's version and both quite different from the new BAD version I tried a couple years ago. I have had three 1974-1975 Twin Reverbs all side by side in my workshop at one point and despite being made within the same 12 month window to the same circuit, they sounded quite different. Even after servicing them and converting them to AB763 BF circuits, there was enough component variation that they still sounded different piped through the same cab, more so each with their own speakers. There's a good chance they all sound different today then they did then, and in fact I know one does because I still have it and a few more resistors have drifted way out of spec and need replacing.

If you don't have the original amp in the same condition it was in when modeled you simply don't know too much about accuracy.
Maybe it's a wording issue. The previous generation of modelling gave me results that matched my expectations. Factoring in what's gone before, the current results don't match my expectations. The models could be totally accurate but in a flawed test and lead to false positives.

Im not saying that isn't the case, but I do think the results I'm hearing are not in line with what I'd expect - and they dont seem to be isolated cases, but a general thing across several models. I'd look past the odd amp being different as that kind of random variation, but if it happens a few times, then it suggests something else might be going on. Let's not forget all the legacy Helix (and other brands) amps are different to my specific ones, and they got close enough. No one mentions tolerances and parts being different when the results are close (which is the case more often than not IME).


If only we saw the often used statement of "the model closely resembles our reference amp"
I'm sure IK said that with their Rectifier emulations in Amplitube, and I bet they performed accurately to their testing set up. The caveat being that the load is totally skewing the results. There could be a valid reason why the amps are behaving perfectly accurately, but also giving some unexpected results. Its not as binary as good or bad.
 
TBF, Im not the first one who's questioned the SLO. Several users have noticed it sounds different to what they expect. I'm not saying it's wrong, but I do think it's odd. It's not one amp either - there has been the 5150, the jubilee, the IIC+, the SLO. It just depends what is under the microscope in any given moment. Some things have been attributed down to a cab block/SIC bug. That makes sense for sure, and its good its fixed.

I think all companies who are proud of the accuracy of their modelling should do this. The whole reason I came back to Line 6 in the Helix generation was because I was impressed with how accurate the modelling was when compared to real amps. It required videos from @GuitarJon and Leon and a few others, mind. I can only think of a few examples that do this:



Just looking through the comments section and I think it all seems to rub off quite positively?

Line 6 would be mad to get involved on every tonal discussion and are understandably just looking from the distance. I know the concerns are being looked at. Regardless, if they just said "hey, the reason things are quite different before is because this time round we did _______ because _______" then everything will make perfect sense to me. In fact, I think comments like this in the past have been what's made users more in tune to the influence of impedance curves and input levels etc.

As it stands, the lack of information (as to why the models are different, and what if anything the user needs to do to address the differences) is just going to lead people to speculate.

its also wild to me that certain people think that pointing out unexpected differences are an attack or poking. It couldn't be further from it - I want to understand what's going on. If users understand the behaviours and quirks of software, they get better results - thats a win for all. I want things to be the best they can be, and it all leads to helping to achieve the best results.


To be clear, I'm fine with anyone doing a comparison of Line 6's Agoura model of amp X and their own personal amp X. It's a data point, and that can absolutely be useful. Also, Line 6 makes mistakes and I personally would want those to be identified so they can fix them.

They would want those to be identified so they can fix them!

But people aren't just speculating on too litlle information....they're jumping to definitive conclusions. Line 6 has said they're taking a look at the behavior, but they're not going to respond with Fractal Audio-like speed where Cliff announces what's off the next day and has a fix done over the weekend.

The thing just launched less than 90 days ago, and they're killing bugs and turning on bedrock features. Amp accuracy retesting has to be at the bottom of their priority ladder at the moment.

Until they have something to say on that matter, people should pump the brakes and wait.
 
Let's not forget all the legacy Helix (and other brands) amps are different to my specific ones, and they got close enough
See.... I think you could read that in the opposite way too.

If the amp models from OG Helix and other brands can get close to your amps are that are not the same model (circuitry and tubes and component tolerances too) then that tells me they're not that accurate. Because again I wouldn't expect a model of a proper SLO100 to be able to sound like a modded Jet City.

But that's just off the cuff. Without properly knowing how the sausage is made, you just can't say what the issue is or isn't.
 
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