The Elusive "Tube-ry Feel" of Axe-Fx III

I don't feel like I'm missing anything regarding the feel when playing through monitors or headphones, however when playing through the SS power amp + cab (SD Powerstage 170), I feel like I don't get the same headroom as when playing through the equivalent tube head (which might be due to the SS amp compression, I don't know). So far the amps I compared to were the EVH5150III and the JVM205 Heads through a Marshall 4x12. The tube amps just seem to have that extra bounce and transparent note attack vs the more congested feel of the Axe+SSPA combo. YMMV. The last few FW updates (9-12 especially) have been a constant improvement in that sense though so keeping fingers crossed for some more Cliff epiphanies :)
 
I run a Mesa mark V through a Mesa 412 slant stereo cab. On the left is my tube rig on the right is my axe fx through a matrix gt1600fx. I've got a Mesa c++ preset as my main sound and I can a/b the real rig against the digital one. The feel is ultra close. So close that I think the differences I think I feel might just be from the sound drop between switching the rigs.
 
I bought an axe fx III exactly 1 year ago, previously I had the axe II and then an ax8.
With those, after some time of owning and using them and despite sounding pretty good, I noticed I was almost "forced" to play in a different way compared to my old Hiwatt amp, I tended to dig in more with the pick to compensate for something missing in the tone.
After some investigation I found out that happened cuz I was missing some "bloom" and fatness, and the attack seemed too fast and too high in volume.
I was able to partially replicate that by tweaking some advanced parameters speaker comp, speaker drive and dynamic depth for example.

I don't know if those are the same things you define as "feel" but they probably are for me.

Then I switched to the axe fx III and the first thing I noticed when I fired it up was that the feel I struggled to get on the ax8 was available right out of the box with no tweaking.
I can't be sure if it's now identical to a tube amp, cuz at this point I haven't played a one for a few years, but my memory tells me it's much closer than the ax8 was even after those tweaks.
With a few further adjustments to the speaker parameters and the addition of the impedance curve of my personal cab I consider it perfect now (at least for now).

PS: among those I've tried, the only other amp sim that comes close (but still not the same) to the axe fx III in terms of (what I consider) feel is Mercuriall Spark set at the highest quality, maybe you could try that in the meantime to get a rough idea of what improvement to expect.
If you have a PC powerful enough to try it with an acceptable latency, it's a quite heavy plugin
Thank you, that's an excellent response. I think you and I are likely talking about the same aspect of the "feel", that's very much aligned with my experience, e.g. SS responds fundamentally differently IME in the past, regardless Helix, Axe8 or FxII, which I personally attribute to the lack of real tube power sections (but I am fully aware that I could be wrong).

Then again, in your experience FXIII somehow does much better in that regards, this is the most intriguing part for me :) I may just stop waiting for FM3, and grad the big III instead!

The OP feels like nothing gives the tube feel that his Helix does, but why is this part being overlooked?

"On the other hand, when plugging my Helix into the power section of a Tube amp, I find that feel is there. "

He's not getting the tube feel from the Helix, he's getting it from an actual tube power amp. That's not a valid comparison to the other modelers unless they are also run through a tube power section.
See @DLC86 's post above and my response :) Yeah, I personally attribute the "feel" largely to the actual power section response outside of the modeler itself, but I could be wrong, and I hope I am ;-)

I don't feel like I'm missing anything regarding the feel when playing through monitors or headphones, however when playing through the SS power amp + cab (SD Powerstage 170), I feel like I don't get the same headroom as when playing through the equivalent tube head (which might be due to the SS amp compression, I don't know). So far the amps I compared to were the EVH5150III and the JVM205 Heads through a Marshall 4x12. The tube amps just seem to have that extra bounce and transparent note attack vs the more congested feel of the Axe+SSPA combo. YMMV. The last few FW updates (9-12 especially) have been a constant improvement in that sense though so keeping fingers crossed for some more Cliff epiphanies :)
Thank you @alethomantis , this is very much in-line with my experience of modelers being lack of feel, I think we probably are talking about the same aspect of feel as well. May I ask which AXE model are you using?
 
I run a Mesa mark V through a Mesa 412 slant stereo cab. On the left is my tube rig on the right is my axe fx through a matrix gt1600fx. I've got a Mesa c++ preset as my main sound and I can a/b the real rig against the digital one. The feel is ultra close. So close that I think the differences I think I feel might just be from the sound drop between switching the rigs.
Besides "feel" might mean different things for different people, the "feel" discussed in this thread, for me, is largely depending on the players playing dynamic, it's most obvious when playing with nuanced dynamics:
1. This "feel" for heavy hitters is likely largely a moot point.
2. This "feel" for high gain tones is also likely a moot point.
3. For clean to low gain tones and dynamic players, IME, SS feel flat, lack of headroom, responds too fast/immediate, less bloom etc, regardless of the modelers I had experience with. And I am hoping AXEIII would be different in this regard.
 
Thank you, that's an excellent response. I think you and I are likely talking about the same aspect of the "feel", that's very much aligned with my experience, e.g. SS responds fundamentally differently IME in the past, regardless Helix, Axe8 or FxII, which I personally attribute to the lack of real tube power sections (but I am fully aware that I could be wrong).

Then again, in your experience FXIII somehow does much better in that regards, this is the most intriguing part for me :) I may just stop waiting for FM3, and grad the big III instead!


See @DLC86 's post above and my response :) Yeah, I personally attribute the "feel" largely to the actual power section response outside of the modeler itself, but I could be wrong, and I hope I am ;-)


Thank you @alethomantis , this is very much in-line with my experience of modelers being lack of feel, I think we probably are talking about the same aspect of feel as well. May I ask which AXE model are you using?

The III with the latest firmware (12.08 beta)
 
Wow, there's a lot of people in this thread getting defensive over a thing the OP isn't saying. He's asking what your subjective experience of the feel is for a products he's waiting for order (FM3) and most of the responses are "I'd never give up the versatility and reliability for something like feel". I'm sure he already knows the benefits, and no one is questioning the trade-off you decided to make going digital. But OP is curious what to expect in this aspect.

Never noticed the "feel" of an amp? That's fine, it's not a concern for you on the Axe FX either and this probably isn't your thread. I know for one I've sat down in front of an amp before I had no intention of buying, but something about it was intoxicating to play. The sound, the way it responded, it just made me feel like I was playing better and wanted to keep playing. Many others talk about things like this as well. It's hard to articulate why, and as with most things that are somewhat subconscious not everyone is necessarily consciously aware of it to articulate their experiences with.

OP isn't saying the Helix is better, or that modelers suck. He's saying there's a certain feeling when playing a tube amp he has experienced, which he hasn't yet experienced with modelers, unless the modeler is plugged into a tube power amp like he's tried with his Helix. Has anyone else here experienced this. Have they compared with an Axe FX and found that it's closer than others? Are there any tips or secrets to tweaking that feel he should know about?

As others have alluded to, the Axe FX models many parts of the chain. The Preamp, the Power amp, the power tube characteristics at volume. The Supply voltage sag amplifiers exhibit when pushed hard. The affect of that sag on the preamp (unless that interaction is disabled), the interaction between the pre and poweramp, the interaction between the power amp and the cab (selectable impedance curves), the behaviour of the speakers when pushed hard, etc. any of these things are tweakable and togglable, so you have lots of options to try to see which affects the feel you like.

I honestly expected this thread to be a lot more helpful. As others have mentioned, you can use Supply Sag and B+ Time Constant settings in the advanced amp parameters to tweak that behaviour is often something people like for getting the right feel. The Helix also has a Sag setting which works around the same behaviour. Other settings I've seen people talk about really making things feel good is enabling some of the "Gain Enhancer" in the output dynamic setting of an amp. This is there to emulate the affect of a loud speaker reverberating the strings themselves to cause a bit of a gain feedback look where the note you play vibrates itself and makes itself stronger. When it was first released people found setting it to 1 or 2 really helped things feel a little more like they felt when standing in front of their cranked amp, or why they felt like they had to turn the gain up on their Axe Fx more than their amp.

Hopefully some others who have identified differences in feel and did some experimentation with settings to hone in on it can chime in.
 
I run a Mesa mark V through a Mesa 412 slant stereo cab. On the left is my tube rig on the right is my axe fx through a matrix gt1600fx. I've got a Mesa c++ preset as my main sound and I can a/b the real rig against the digital one. The feel is ultra close. So close that I think the differences I think I feel might just be from the sound drop between switching the rigs.

I would like to try the Matrix power amps again to see if the feel is different with the newest hardware/firmware - I had tried a GT1000fx with an AxeFx2 a couple of years ago and sent it back after the trial period. I'm also somewhat confused as to what Matrix calls tube-like dynamics, which I assume is a slowed down response of the amp as opposed to the faster response of the SD Powerstage and other FRFR SS amps (?). I don't understand why this is needed if the interaction of the power section with the speaker should be modeled int the Axe.
 
No one can tell you what you are going to "feel", that is why we call it that. It's personal. If it's done properly it should vary from amp to amp. If the Axe models 200+ amps and it does so accurately, some should feel one way and others should feel notably different. Whether that is going to translate well for you or how that is going to compare with your Helix experience, no one can say. If the Axe itself has a 'feel' then the Axe is failing to be an accurate modeler, IMHO.

You could easily dislike both products in this regard (you need to use the Helix with tube power so it is not working by itself to your satisfaction). Shrug.

I would guess virtually every user here is going to tell you they think the III is best in class across all modelers because that is the nature of self selecting sample data; but that only tells you that people who buy the unit and hang out on the forum find it satisfying, which to be honest, is probably a completely information-free statement.

Summary: Try it and see. There is a free return policy, IIRC.
 
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I would like to try the Matrix power amps again to see if the feel is different with the newest hardware/firmware - I had tried a GT1000fx with an AxeFx2 a couple of years ago and sent it back after the trial period. I'm also somewhat confused as to what Matrix calls tube-like dynamics, which I assume is a slowed down response of the amp as opposed to the faster response of the SD Powerstage and other FRFR SS amps (?). I don't understand why this is needed if the interaction of the power section with the speaker should be modeled int the Axe.
Exactly, I do not understand that part either...

Wow, there's a lot of people in this thread getting defensive over a thing the OP isn't saying. He's asking what your subjective experience of the feel is for a products he's waiting for order (FM3) and most of the responses are "I'd never give up the versatility and reliability for something like feel". I'm sure he already knows the benefits, and no one is questioning the trade-off you decided to make going digital. But OP is curious what to expect in this aspect.

Never noticed the "feel" of an amp? That's fine, it's not a concern for you on the Axe FX either and this probably isn't your thread. I know for one I've sat down in front of an amp before I had no intention of buying, but something about it was intoxicating to play. The sound, the way it responded, it just made me feel like I was playing better and wanted to keep playing. Many others talk about things like this as well. It's hard to articulate why, and as with most things that are somewhat subconscious not everyone is necessarily consciously aware of it to articulate their experiences with.

OP isn't saying the Helix is better, or that modelers suck. He's saying there's a certain feeling when playing a tube amp he has experienced, which he hasn't yet experienced with modelers, unless the modeler is plugged into a tube power amp like he's tried with his Helix. Has anyone else here experienced this. Have they compared with an Axe FX and found that it's closer than others? Are there any tips or secrets to tweaking that feel he should know about?

As others have alluded to, the Axe FX models many parts of the chain. The Preamp, the Power amp, the power tube characteristics at volume. The Supply voltage sag amplifiers exhibit when pushed hard. The affect of that sag on the preamp (unless that interaction is disabled), the interaction between the pre and poweramp, the interaction between the power amp and the cab (selectable impedance curves), the behaviour of the speakers when pushed hard, etc. any of these things are tweakable and togglable, so you have lots of options to try to see which affects the feel you like.

I honestly expected this thread to be a lot more helpful. As others have mentioned, you can use Supply Sag and B+ Time Constant settings in the advanced amp parameters to tweak that behaviour is often something people like for getting the right feel. The Helix also has a Sag setting which works around the same behaviour. Other settings I've seen people talk about really making things feel good is enabling some of the "Gain Enhancer" in the output dynamic setting of an amp. This is there to emulate the affect of a loud speaker reverberating the strings themselves to cause a bit of a gain feedback look where the note you play vibrates itself and makes itself stronger. When it was first released people found setting it to 1 or 2 really helped things feel a little more like they felt when standing in front of their cranked amp, or why they felt like they had to turn the gain up on their Axe Fx more than their amp.

Hopefully some others who have identified differences in feel and did some experimentation with settings to hone in on it can chime in.
Thank you @IronSean for getting into the technical setting aspect of the discussion, this is exactly what I am hoping, really appreciate it! The sag is another aspect of "feel", I don't feel that lacking in Helix or Axe8 before fortunately, i.e. it largely works well after some tweaking.

The B+ Time Constant sounds super interested, noted that down, thanks!

P.S. Just want to set the record straight, I totally admire @FractalAudio 's work, they are the leader of guitar amp modeling with no doubt. If anyone could get this really right, my bet will be on Cliff and his team, based on my limited observation and understanding how they operated and prioritized things.
 
Exactly, I do not understand that part either...


Thank you @IronSean for getting into the technical setting aspect of the discussion, this is exactly what I am hoping, really appreciate it! The sag is another aspect of "feel", I don't feel that lacking in Helix or Axe8 before fortunately, i.e. it largely works well after some tweaking.

The B+ Time Constant sounds super interested, noted that down, thanks!

P.S. Just want to set the record straight, I totally admire @FractalAudio 's work, they are the leader of guitar amp modeling with no doubt. If anyone could get this really right, my bet will be on Cliff and his team, based on my limited observation and understanding how they operated and prioritized things.
The tube amp feel to me comes from the power amp stage and all it’s interactions with the speaker/preamp etc. The axe fx aims to model all of this. For me feel comes down to
1. A squishy non immediate response - supply sag, transformer match, b+ constant can easily get you there.
2. Touch sensitivity - I don’t have to do anything special for this, maybe some output compression or gain enhancer and run everything reasonably loud.

The axe fx 3 really stepped up the modeling where everything feels and sounds good out of the box. I had the AX8, where everything sounded good, but I did not get the right feel without a lot of tweaking.
 
@Feflicker I havent really made any sweeping changes. I make minor tweaks if the overall preset is right but the reverb is a little much or delay needs and adjustment for a specific idea. That said, all my core presets are bases for my various guitars and bass. Its also usually 30 seconds in a block and Im back to tracking (as thats what I've been doing most lately).
 
Am I the only one not constantly tweaking my presets? I usually turn it on and say "yep, still sounds incredible" then play my guitar....
It's much the same for me. Once I create a preset, about the only time I feel the need to change things is if a FW update makes a noticeable change to the tone.

I'm a one preset per song guy (cover band), and when we add a song to the set list, it usually only takes me a few minutes to pick the amp(s) and cab(s) I need for that song. I don't spend a lot of time dialing in the tone, and pretty much never go deep into the advanced parameters. If a certain model isn't sounding the way I want within a few minutes of playing with the gain and BMTP knobs, I'll either change amp models, cab IRs, or both.
 
I don't have time at the moment to read through this thread so apologies if I repeat what's already been said here. I'll give you my totally non technical opinion as a long time tube amp player that the Fractal products have been the only modelers that have given me the "feel" of a tube amp. That hard to explain feeling that occurs between my brain -> fingers -> strings -> to ears. Fractal has computed this and put all the emulations in place that convince my consciousness that I'm plugged into a tube amp. I still jump back and forth and love all of it. I love even more the consistency I get from the Axe.

I've owned all 3 major models of the AxeFx in some flavor, various Line6 products including the Helix (and Helix Native), Native instruments guitar rig, Digidesign Eleven, played with countless plugins, IK products just about everything I can get my hands on. I'll say I find value and have gotten really awesome tones out of all of these products. Some I consider unique on their own right and what I love about them have nothing to do with trying to recreate preexisting pieces of hardware. Some of them I am amazed at how well or close they get. My opinion is that Fractal is by far the winner on the emulation and would be my choice for winner on originality with what they bring all their own although others are right up there with them.

I did use the Helix as my main rig for a couple of years. I thought it was an awesome piece of gear and there are some things with their software and hardware from an end user/programming/performance aspect that I prefer. But I can also flip that and say exactly the same thing about Fractal. At the end of the day there is a "way" that was decided upon. I have been really impressed with how open Fractal seems to be to implementing a good idea and how quickly those can become part of the product. They iterate SO MUCH faster than Line6 its kind of staggering. I do love Helix Native... its amazing having that at my fingertips in a DAW wherever I go. Not sure we'll ever see that from Fractal but who knows?

I had great sounds programmed into my Helix and was super happy with it. So much so that my AxeFx III sat in a rack in my home studio gathering dust for months after I purchased it. Once I finally got the time to sit with it I was sad I had waited so long. It sounded so good to my ears and "felt" like I expect my rigs to feel. I brought it in a week or so later to rehearsal only having a few sounds dialed in really and my band mates reaction confirmed it all. They were all like "that! I dunno what you just brought in but use that from now on". None of them are gear heads and didn't even really notice I had brought in different gear. They just thought I was really nailing it and everything sounded better than normal.

I decided to keep the Helix too... for a while... but then decided I'd sell it because I hate gear not getting used. I have Helix Native still so now I have all the things and someone else can use the hardware and its not gathering dust! Whatever the next new shiny in the modeling world is ( probably the Neural DSP) I'll be checking it out. That is just what I always do. But I have my doubts I'll be switching from the AxeFx again for a long time if ever. The community, their ability to deliver new features, the quality, and the fact I always end up back with them means I am only likely to possibly integrate something else in my rig alongside a current Fractal product.
 
For clean to low gain tones and dynamic players, IME, SS feel flat, lack of headroom, responds too fast/immediate, less bloom etc, regardless of the modelers I had experience with. And I am hoping AXEIII would be different in this regard.
This is where I live most of the time. You won't be disappointed.

You keep saying the same thing about solid state amps and I don't want to beat a dead horse... But again, the Axe Fx models all the actual circuitry of each amp.

This is NOT how (most) other modelers work. From what I've read of Cliff's comments in the past, the others are mostly just layers of filters/EQs.
 
Thank you, that's an excellent response. I think you and I are likely talking about the same aspect of the "feel", that's very much aligned with my experience, e.g. SS responds fundamentally differently IME in the past, regardless Helix, Axe8 or FxII, which I personally attribute to the lack of real tube power sections (but I am fully aware that I could be wrong).

Then again, in your experience FXIII somehow does much better in that regards, this is the most intriguing part for me :) I may just stop waiting for FM3, and grad the big III instead!
For the record, I've been using solid state class D amps and powered speakers for quite some time now, and my impressions are based on that use.
My current setup is two Atomic CLRs (also run as PA for vocals) and an IcePower power amp (which is basically a diy SD Powerstage) into a 2x12.

I think, if the power amp modeling and its interaction with the speaker(s) are done right in the digital realm, there should be no need to use a tube power amp to get that feel.

Anyway, I hope you'll find what you're looking for ;)
 
however when playing through the SS power amp + cab (SD Powerstage 170), I feel like I don't get the same headroom as when playing through the equivalent tube head (which might be due to the SS amp compression, I don't know)
How did you set the parameters in the speaker drive page in the amp block?
For me the key to get the best feel with an SS amp is using these settings (even though I use and prefer them with monitors and headphones too):

  • Output mode: SS pwr amp + cab
  • Speaker time const: between 150 and 200 ms
  • Speaker compliance: 50% or more
  • Speaker compression: set to achieve 2-4 dB of gain reduction on the meter

And if you have the opportunity to measure the impedance curve of your cab that might be the final touch
 
I would like to try the Matrix power amps again to see if the feel is different with the newest hardware/firmware - I had tried a GT1000fx with an AxeFx2 a couple of years ago and sent it back after the trial period. I'm also somewhat confused as to what Matrix calls tube-like dynamics, which I assume is a slowed down response of the amp as opposed to the faster response of the SD Powerstage and other FRFR SS amps (?). I don't understand why this is needed if the interaction of the power section with the speaker should be modeled int the Axe.
I think the tube like Dynamics is mostly marketing hype. I tried the following experiment: I ran the signal from the Mark V's effect loop via the 2nd output on my mxr 10 band eq, into the matrix power amp and the sound was considerably flatter and had no sag or bounce to the feel. It was almost too tight and immediate. What's interesting is bypassing the Mesa's power amp let me see how little of a difference there is in the preamp section across the modes. A lot of the tone shaping in that amp's modes comes from power amp configurations.
 
Besides "feel" might mean different things for different people, the "feel" discussed in this thread, for me, is largely depending on the players playing dynamic, it's most obvious when playing with nuanced dynamics:
1. This "feel" for heavy hitters is likely largely a moot point.
2. This "feel" for high gain tones is also likely a moot point.
3. For clean to low gain tones and dynamic players, IME, SS feel flat, lack of headroom, responds too fast/immediate, less bloom etc, regardless of the modelers I had experience with. And I am hoping AXEIII would be different in this regard.
1. What's a heavy hitter ? Do you mean playing hard or digging in most of the time? If so, then I understand what you're saying.
2. High gain definitely has its own feel that still needs to be modelled otherwise it will feel too stiff and immediate. If I turn power amp modelling off in the axe fx and play through the ss power amp it is exactly as you describe SS feel.
3. I agree with you on SS power feeling flat if the power amp modelling in the unit isn't robust.

I say try it out. You might find what you're looking for and if not at least you gave it a chance and can send it back. In case you're wondering, I play ch1 clean, ch2 crunch, and ch3 mark iv mode on my Mark V. It's not all high gain.
 
How did you set the parameters in the speaker drive page in the amp block?
For me the key to get the best feel with an SS amp is using these settings (even though I use and prefer them with monitors and headphones too):

  • Output mode: SS pwr amp + cab
  • Speaker time const: between 150 and 200 ms
  • Speaker compliance: 50% or more
  • Speaker compression: set to achieve 2-4 dB of gain reduction on the meter

And if you have the opportunity to measure the impedance curve of your cab that might be the final touch

I have the output mode set to SS amp + cab and no speaker compression, which means the other speaker parameters (compliance and time const) should have no influence. Speaker compression seems to tame the highs considerably imo. Furthermore, I feel like I shouldn't need it since the natural effect of speaker compression only emerges at very high volumes and should also happen naturally if I would run the Powerstage very loud.
It would indeed be interesting to see if the correct impedance curve would improve things, even though there seems to be quite a few 4x12 impedance curves in the device already, which should give a feeling of how things change.
 
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