Confused about Axe FX amp controls

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rich2k4

Inspired
I'm still in the research phase, preparing for a purchase of either an Axe Fx 2 or Ax8 (Haven't decided yet). Anyways, I've been going through Yek's Amp write-ups and they have been helpful, but still a little bit confusing to me in regards to some of the knobs and their uses.

For example, most fender amps only have a volume, not a master volume. I am assuming in this case, leaving the master volume at 10 on the axe fx would mimic this behavior. However, what happens when you turn the master down? Does it actually effect the tone, or is it completely disconnected no matter what setting it is at? If it is disconnected, why have it on the screen? Shouldn't the knobs in axe edit, change to reflect what is actually on the amp?

I am assuming the unused knobs are still there for those that want to do things that the original amps aren't capable of, and to shape the tone to be something custom but based off the original amp?

There are a few other amps that have similar situations to this. For example, on the Dumbles, the overdrive section has a ratio knob. What does that correspond to in Axe Fx? I don't think Yek's write-up mentions that. And if there is no knob that is equivalent to it, then is it set to some default setting internally?

Last question, and hopefully it makes sense. Do the values of the knobs in the axe fx correspond to the values on the amp? For example if I am using a plexi, does 7 on the treble in axe fx mimic 7 on the real amp exactly? What if you have some knobs that go to 12, but the axe fx control only goes to 10?

Also, I noticed for the Tiny Terror writeup that it says the model is based on a neutral tone stack, and that to get a authentic sound, set the tone controls in axe fx to noon. My question is, why is the amp modeled like that in the first place, shouldn't the axe fx controls mimic the tiny terror's controls exactly, not based on some pre determined tone stack value? Does that mean if I set tone to 2, it is the same as having the amps tone on 2?

I hope all of that makes sense. I apologize as I am not familiar with amplifier physics. This is something I always wondered about though because I notice a lot of modelers have some generic set of controls for every amp. If I was designing it, I would have the controls change for each amp to mimic exactly what is on the amp, anything extra would be in advanced options. If anyone from Fractal could chime in and explain this design choice, that would be cool. It would be a lot less confusing because it would be like looking directly at the amp in person.

Thanks.
 
The topic of the controls being "authentic" to the amps vs. generic comes up fairly often.

As is stands now, the controls are somewhat generic. The controls do change a little. E.g. some models have Input drive and overdrive. Some have Hi cut.

But for the most part the controls are generic.

It depends on the control and amp model as to what a control will do if it's not on the original amps. E.g. when the original tone stack doesn't have a Mid control, the mid control in the model is typically functional.

For controls that are in the model but not in the real amp, the default value is authentic.

If you want to use the amp models authentically, then some learning about the real amps helps. There is a sticky thread that searches the posts by @yek of a series on every amp model. These posts describe the original amps and give tips etc. In these posts you can find out what controls to use in the amp model for authentic results.

The fractal amp models tone stacks and gain, master use a 0-10 scale even if the real amps do not. I made a translation table that is floating around the forum somewhere for translating to some other typical control ranges.
 
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rich2k4 said:
Also, I noticed for the Tiny Terror writeup that it says the model is based on a neutral tone stack, and that to get a authentic sound, set the tone controls in axe fx to noon. My question is, why is the amp modeled like that in the first place, shouldn't the axe fx controls mimic the tiny terror's controls exactly, not based on some pre determined tone stack value? Does that mean if I set tone to 2, it is the same as having the amps tone on 2?
Click to expand...

Cliff:
"The tone control is actually a high cut control in the power amp and is therefore replicated by the Hi Cut parameter. The Hi Cut set fully CCW is equivalent to the amp’s tone knob fully CW.
​
http://forum.fractalaudio.com/threa...els-citrus-terrier-orange-tiny-terror.112702/
 
Myself I never use a stock amp preset and I'm now turning 75% of the knobs in the amp block to find my sound . I def want to fully understand what every value will do to my tone. I really enjoy having access to these algorithms and being able to change how things sound and feel.
 
Simplest answer is don't worry about it. Turn knob to the point where it sounds good. Enjoy playing.

I think too many people get wrapped up in thinking "oh, well so and so rock star that uses brand X amp sets this knob to 7.8, but then when I did that on the Axe I didn't like the tone, but I do like the tone with that knob set to 5, what do I do?" type of mentality. Its not going to be an exact match as different amps use different pot tapers etc.

So maybe a Fender amp doesn't have a mids control, or the ability to change to a different type of tone stack etc. That is the limitation in the real world, but with the Axe it isn't, so if it sounds good, I think it makes more sense to just do it, rather than limit myself for the sake of remaining authentic to the model.

Its great to have a bunch of accurate starting points, but why stop there ?

I was always taking my amps to get mods done, and spending a ton of money doing it. With the Axe I can have that ability without spending a time which is awesome.

It seems to be a strange 180 for a lot of folks when it comes to digital modeling. In the real world its all about mods, swapping tubes, speakers etc to get a pleasing, custom sound. Digitally though, people seem to want to know the "right" stock speaker IR, how to set the knobs for the real amp etc. Its like they want to take all that customization away for some reason.

Its like a bragging right to say here is my 100% authentic stock sounding amp when it comes to modeling, yet in the hardware world, no one brags about that. Its all about how your amp guru hot rodded it, changed a cap value for less brightness etc etc.

In hardware, having this one of a kind, custom modded, "top secret", amp is the goal, at least for a lot of players. I would think more people would think that way in the virtual world. Take a given amp model, change out the tube types, lower the bias, change preamp hardness, swap the tonestack, add a PPIMV, move its position around, play it through a custom mixed IR of 3 different cabinets etc etc.

Then when people say, wow! great tone, what amp model are you using ? You can say its a custom made, "top secret" model that no one else has. Or you can just use a great sounding stock model, maybe tweak one knob, and still say its a custom done offering. People love what they can't have LOL
 
@lqdsnddist I get your point. A modeler like the Fractal offers up more possibilities than the real amps so go for it.

But, learning the authentic amp controls can make a model that seems meh be your go to.

For example, the deluxe Tweed. Keep everything at default and just crank the Treble. The Treble models the original amps single Tone control. With just the Treble cranked, this amp model is glorious. I don't think I would have arrived at such a great tone if I hadn't learned the way that amp is modeled and what the Fractal controls represent.
 
Lots of good questions there I have asked myself recently after a month or two owning the Axe.
Lots of good answers too.
What everyone says is right and equally wrong. Why should it matter? Well to some people it does for whatever reason that may be.
I'm in the middle. I want to hear authentic as possible simulation then go from there and I believe that's as simple as loading the default and tweaking the very basic controls. Then get funky and start messing with stuff.

One key thing I've learned though is that you can have all the settings of whatever source material down to the finest details including mods and tube types etc... But at the end of the day it's probably not going to sound anything like you expect because there's just far to many variables.
That might be bad that might be good but one thing is certain it's definitely capable of producing any tone you could ever want, you just got to find it.
 
The questions the OP brings are similar to what nearly every person coming to modeling technology will wonder about. If you're modeling, how accurate is your model, and if the amp was worth modeling what is the point of going outside what it would do in the first place? Keep in mind going forward that it is rare (I think non-existent, but that's just an opinion) for two amps of even the same model/vintage to react exactly alike, so variation has always existed from the assumed perfect "standard" folks refer to when comparing.

The answer to it all lies in the model, not the amp. These amps are modeled because they can be improved in one way or another. It might be less weight, less cost, availability to persons who could never own the amp, the ability to carry a fleet of amps/cabinets/effects/switching systems in two rack spaces, etc. And yes... more flexibility than the original specimen can offer. In my experience, every Axe Fx model will do all the original would, but almost more importantly (at least to me) it adds things that carry the original further down the musical road.

One oft missed point in modeling of this quality, and something FAS tries to widen your peripheral musical vision with, is that these so-called standard sounds didn't always exist. Someone made a circuit, mated it to a speaker, set the controls a certain way, and people liked it so others used something similar. Bam, a standard. If I were pressed to guess what most impresses someone like Cliff Chase, it would be someone using his technology to create something that is an evolution to the future rather than a perfect reproduction of the past.

Sorry for the long answer... a beautiful rainy morning in Texas and maybe I am feeling a little philosophical. :) The answer, in short, is that the models will do what the original did if you take the time to educate yourself on both the original and the Axe Fx control system. It is a wonderful thing that the Axe Fx didn't stop there, though. That has been the downfall of most modeling in the past, and I love that FAS decided to lose sight of that limitation when designing their products.
 
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well if you think about it.. I'm not 100% sure but most of the amps actually work from the same algorithm right? I mean there's a few added knobs in certain models but the algo is the same....Cliff and team probably match the real amp right from Axe Edit or another process ( this is all speculation ) I really don't care about models and the authenticity of it, but I understand where you come from... Seems like every model I dial in just comes to my favorite tone in my head...lol
 
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Some of us spent much of the late 90s changing caps and resistors in Fender and Marshall tone stacks, soldering caps onto rotary switches to have switchable bypass caps on the preamp cathode resistors, messing with plate resistors to move the preamp bias to change clipping asymmetry, building PPIMV circuits, the list goes on. It was pretty time consuming, but the results were often worth it. I think a lot of that messing around spawned some of the boutique amps that are on the market now.

The modeling concept messed with my head a little when I first started working with the Axe-FX, until I realised that many of the advanced features have been put in there to mimic things we used, but in a much better way. For instance, lots of people used to change the "mid" resistor in Fender tone stacks that didn't have a mid control to get them a little less scooped. Only problem was that as you went up in value of the resistor the treble and bass controls became much less effective. Modeling is far less limited, and you can get a great Fender core tone, and then just do whatever you like with the overall EQ to get a tonal palette that suits what you are trying to do.

I think the key to getting the best from modeling is to avoid chasing rainbows, and to free yourself from the idea that getting the perfect replication of classic amps can be the ultimate goal. The day I got my Axe-FX II XL I started with the '59 Bassman preset, and immediately recalled what I like, and more importantly what I don't like about those amps. None of them were perfect, none of them were sonic nirvana, and the Axe-FX can give you not just a great sounding Bassman, but one that actually suits what you want to do. Ultimately, I think it's a better way, and that Cliff Chase and his team have found a way of achieving this that suits engineers, musicians, and in my case someone that does a bit of both.

Liam
 
Two points to think about that have been brought up many times in the past:

#1 - for many of these amps, especially the older ones, there are no two that are exactly alike. What is 7 on one amp might be 5 on another, and 8 on another. I'm talking about the same model of amps. Try finding old Plexis that sound exactly alike. They just don't. So, Cliff models the one HE HAS. It will be different than the one YOU have.

#2 - There is probably some real merit to keeping Axe Edit (and the front panel) somewhat standardized. People learn (and love) to tweak amps, and then if the control they use isn't there for an amp... then what are they to do?


That said, I do somewhat like the idea of a future version of this thing that takes "modeling" an amp to the next level, and brings about an interface that is true to the original equipment. Yes... it is all about the sound, but I do have to admit that I did the idea of owning some form of all of these amps I could never otherwise get, so I just want more of that experience. In the end, I might not even like that from a practical gigging musician's perspective. The Axe FX is a pro's tool, and I would not want to make it "toy like". It just sounds kind of fun I think.

It would probably be a real development nightmare, and I really would not want to give up any controls... but probably have an amp page (or an option maybe) in AXE Edit for authentic controls, and then maybe the rest are on advanced tabs. (Again... I'm just fantasizing here... I have no expectation this is actually ever going to happen). I'm trying to image how you would model something like a Mark V with all of those options and controls, (and those on the back of the amp as well!) vs an old Fender or Marshal with just a few controls. It would be interesting to say the least.
 
If there is one thing I've learned from owning my AXE FX 2 XL Plus for about 3 months now is:
When you first get it, go through the presets and listen to them. You may like some and not like others. When you find one you don't like, experiment with it, twist the knobs, even to the point of making it worse. This will give you a better understanding of what the different amps, cabs, effects and settings can do. Learn to use and trust your ears. And just because someone uploaded what he or she thinks is a perfect preset, it may not sound good to you. The reason is first your ears, and then what the AXE is feeding to, the cab or monitors used, etc. But sometimes it's a good starting point to listen to what someone created or tweaked. It gives you ideas on how you want to proceed.
I read and listened a lot, watched a few tutorials, dove into mine with serious intent to learn and pretty much ruined a few presets. When I was comfortable that I could create or tweak intelligently, I restored the presets with the latest ones and created and modified my presets to my liking.
Now, I start from scratch or grab my favorite amp and cab, or ones I never heard, and build from there. I guess I never worried about whether the knob settings are exact. I've owned too many amps in my lifetime, and never worried about that then. I just twisted and listened until I was satisfied.
 
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