1:1 - Let`s talk A/B testing actual Amps to their Axe-Fx II Counterparts

Morphosis

Official G66 Support
When it comes down to compare the Axe-Fx II Amp Sims with real Tube-Amps, I experienced a difference in "feel" I cannot achieve, no matter how much I tweak out the hell out of the Axe-Fx II. Before I will explain that in particular, let me say some words to myself in reference to the Axe-Fx II:

I am a Axe-Fx-Lover. I am the founder of the German axefx.de forum/community, organizer of the first German Axe-Fest in Leipzig 2013 and organizer of the coming up Axe-Fest in Daxweiler/Germany 2014. I would call myself a experienced Axe-Fx user since 2009 with a Axe-Fx Standard (since FW 7.18) and Axe-Fx II (since FW 6). I work as freelancer for the European distributor G66 for minor updates on their homepage.

I`ve experiment and done a lot of comparisons like tonematching my Koch Studiotone Tube Amp into the Axe-Fx (EQ matching with iZotope Ozone & Axe Standard, later on Axe-Fx II / FW6 inbuilt tonematching and wrote a tutorial on that..). Later with FW10 I tweaked a AxeFx Sim with the advanced parameters as long, as it sounds nearly like the actual Studiotone. Under recording situations I get the Axe-Fx to nearly 100% to react and sound almost identical to "the real thing".

I`ve experiment and A/B Impulse Responses to the actual speaker cabinet and convince myself, that this technique is really very, very accurate.

That said, i won`t discuss in this thread FRFR vs. Guitar Cabinets, won`t discuss Volume issues like the "Fletcher Munson" debate or gain/compression / loudness issues when it comes to questions, why some people feel, that the Twins, AC30ies, etc ... in Axe would be to gainy, etc...

Furthermore this thread is NOT about comparisons of actual Amps to their Axe-Fx counterparts UNDER RECORDING situations. NOT about FOH & PA and FRFR translations. I really think i know one or two things about these things. Hoepfully. Not, because i read about or believe, but because i did spent some hours and days to compare those things to myself and have made my experiences with that. (Matrix GT1000; Q12A, Bogner Cube 1x12", Fender & Koch Tube-Amps & Cabinets, Studio Monitors, dozens of live Gigs, FOH experiences, In-Ear experiences, etc...)

My Question is only to the people out there, who have the ability and done (!) AB`ìng their actual Amp to the Axe-Fx II Counterpart under "real guitar player in the room with their amp and guitar cabinet in the room".

And AB`ing Apples to Apples. Means:
Same Player, same guitar, same (or identical) Guitar Cabinet, same room:

Player -> guitar -> ABY-Box -> [AMP (Actual Preamp+Poweramp) ] -> [Guitarcabinet X]

vs.

Player -> guitar -> ABY-Box -> [Axe-Fx AMP-sim (of the actual Amp) ] -> [Guitarcabinet X]

Yes, i know: Udner recording situations it would sound the same. OK, no problem with that, but under "live" circumstances?

The observing Reader will now say: "Hey, you missed the Power Amp beetween the Axe and the Guitar Cabinet!"

YES!
And this is exactly the point i came into trouble!


When i play my Koch Studiotone directly into the guitar cabinet, then this ... i don`t know how to describe it ... this magic thing happens: Call it "more bloomy, more chimey, spongy, three dimensional", whatever you want ... the tone bubbles out of the speaker.

When i use the Koch Studiotones FX Send (only Preamp) OR Line Out (inbuilt Power Soak = ON; Line Out is in reference to the schematics behind the PowerAmp) and go from their into the Matrix GT1000 into the Guitar Cabinet, something gets to be lost. The tone / notes sticks more at the speaker, note seperation get a bit lost, the "magic" disappear. Don`t get me wrong: IMHO the GT1000 is a very good, transparent, well built solid state amplifier, but something is missing than.

The same with the Axe-Fx II: If i play through the FX return of the Koch Studiotone (=2x EL84 PowerAmp) into the Guitar Cabinet the magic happens, i think immediately: "Yeah: That`s it! I`m home - no more questions. It FEELS 100% perfect and "tubish" correct". And when i play through the GT1000 i always think: "hmmm, ... sounds good but something .... something is missing, it could be a bit more .... WHAT IT WAS with the TubeAmp."

Some may say: Yeah, that`s a very subjective thing - and you`re right. But the difference is there! Some may say: "Yeah, are you aware that you "double" the Poweramp thing when playing the Axe-Fx PowerAmp Sim into the real Tube PowerAmp Sim?!". And yes, i know that! So i switch off the Axes PowerAmp Sim - no go. Sounds more bad in comparison to PowerAmp Sim ON with GT1000...

So whats with the Speaker Tab?! Catchwords "current feedback", dynamic resistance (!?), interaction Tube-Power-Amp <-> Guitar Cabinet? This is the last bastion, the missing link a solid state Amp with high damping can`t (and should not!) do & that`s the reason the Axe Sim has to simulate this issue. So i tweaked the Lo and Hi Res ... what i`ve found out:

"flatten" this curve and play through the Tube-Amp in comparison to boost / change or default this setting with the GT1000 makes both amplifier-systems a bit more comparable, but i can do what i want, tweak the hell out of it ... the "right feel", this "perfect interaction" beetween my guitar and the speaker cabinet won`t come to live. For example: A Clean "fenderish" sound and a strat with neck PU: If you stroke the strings you hear those "shimmering", "sparkling" highs to line with the percusive "bottom end" and you think both (lows and highs) are completely seperated... and fill the room. With the solid State Amp this seperation get lost, the whole thing sounds more as if the tone is more sticking to the speaker. It is something different, than only EQing differences. Frequency wise i have no issues with both PowerAmps - there they correspondend well to each other.


So, bring it to the table: Are there guys out there, who have tested their Fuchses, there Matchless, there Twins and Deluxes, their Plexis, Badgers or whatever directly side by side with the Axe-Fx in the room through the same guitar cabinet? And if yes:

- Did it feel the same? And if yes: Which PowerAmp did you use? And if not: What do you think why? What is missing?

I really always thought and believed two things:
First: The "extremely accurateness" Cliff so oftenly stated (and his recordings (!!!!!) give him right!) also in respect to the PowerAmp / Speaker Tab section is much more good enough to believe, that the "correct" and "accurate" amplification have to be done with a good solid state powerAmp (with no impact on the simulated dynamics and sound of the simulation).

Second: The GT1000 should be (one of the) best matches for the Axe to reach this theoretical requirement.


Don`t get me wrong: I highly respect the Axe-Fx as what it is! But when it comes to translate the actual Tube Amp "in the room" it must be amplified. But if the theroetical "correct" (means: No influence but "making loud" what its pulled in) amplification would be NOT a Tube Power Amp (because of their higly influences to the feel/sound - what should be done by the Axe itself) i really ask myself: Thank you for all those incredible boutique Amps, thank you for all those accurate and always improving Amp Simulations, but HOW can i play them really like the actual amp, if i feel there is such a missing link when it comes to amplification and/or interaction with a guitar cabinet?

So i ask you again, you boutique gear, real Amp Owners: Can you? Give the Axe-Fx plus PowerAmp plus Guitar Cabinet you the same feel and satisfaction if you compare that to your actual amp in the same room through the same guitar cabinet? And if yes: What amplification you use for? Are their "special tweaks" to achieve that?

I really, really like to make this experience without using a Tube-Poweramp. Is this possible???

At least: IMHO, what i`ve tried to describe is something, that the more cleanish to crunchy Players will feel, less the high-gain fraction ....
 
Not hands-on but I was in the room for an A/B comparison between the AxeFx and Bogner XTC. Even with different power amps going into the same cab, the two sounded identical. The guys actually playing didn't note any differences in feel.
 
My guess is that the model you are using is not equivalent to the Koch. I know nothing about that amp so I cannot recommend an equivalent model.

I've done EXTENSIVE A/B comparisons between the real amps and the models and with beta5 I consistently fool myself. Before I could usually pick out which was the amp and which was the model, I'd say 70% success rate.

Perhaps you should try a different power amp. Power amps vary greatly.

If none of this works then perhaps the product isn't for you. It is what it is. It is not a tube amp, it's the closest digital product available though. And I say this having compared every digital solution available. I've compared the 11R, KPA, HD500, etc. and the Axe-Fx comes closest to the real thing. The 11R with the right IRs can come pretty close (but you can't load IRs into it so it's an awkward solution) but I can still pick it out 80% of the time or more. In A/B tests I can pick the KPA out every time. It has a signature to the distortion and pick attack that differs greatly from the real amps. I have had no luck getting the HD500 to sound like the real amp.
 
FWIW
Here are my observations after spending quite some time in the same room with my 100 watt vintage Marshall head into one side of a 4x12 and my AFX2 rig including Matrix GT1000 into the other half of the 4x12. I used a Lehle AB switch to go back and forth between the rigs as I repeated the same chords or riffs.
http://forum.fractalaudio.com/axe-fx-ii-discussion/77457-fw-12-leave-lights-i-mean-cab-block.html
I haven't yet loaded the betas in 12.03.
I was waiting for the dust to settle a bit.
But given Cliff's comments about touch and feel and the relationship between pre and power, I am expecting an even more authentic experience... which was really super duper damn close already in 12.xx
 
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My guess is that the model you are using is not equivalent to the Koch. I know nothing about that amp so I cannot recommend an equivalent model.
Sure, this a leak point - this Amp is not in the Axe. But does not matter. The clean Channel is similiar to the JTM45 in the Axe, the Gain Channel goes into Plexi100 territory. But i don`t think, this leak in 1:1 comparison is the really issue to me. Played yesterday one song on a Fender Blues Deluxe Hot rod or something ... same thing... what`s really hard to describe but immediately noticable, when playing the first note ... anyhow ...


Perhaps you should try a different power amp. Power amps vary greatly.

This seems to me a good point. So, if you compare A/B Axe-Sim to the actual Amp in the room side by side through the same (?) or almost identical Guitar Cabinet(s) and come to the conclusion, that the Sim is spot on (also in dimension of "feel") you have to amplify the Axe through anything. So, what did you use? Which PowerAmp? And if Power Amps vary greartly the question come up, if the "accurateness" of modeling would also vary, if you would change the Power Amp? That would be the logical conclusion, if that A/B comparison "in the room through same speakers" would be the only one, but I´m sure that won`t be the case ;)

Also, i really won`t nit picking this. My issue is according to view and preferences more "substantiell" away from "nit picking accuracy" to an actual amp model - whatever this would be. Complicated as german with less english language knowledge to bring it to the point: Does not matter that much, if we`re talking about a Koch, a Fender, or whatever ... fact is: At the moment, i plug the Axe into the return of the Koch or the Reußenzehn 50:50 tube PowerAmp (Marshallesque EL34 type) the whole thing comes to live and sound incredible. I thought this have to be also achievable with a solid state Amp. I tried there also aside the GT1000 a old Class H (ring core transformer) Power Amp with similar Watt Specs. Sounds a bit different, but makes not that "night and day" difference i feel with the Tube Amplifer. It makes me crazy! I WILL AND BELIEVE that this should work also with solid state?!

If none of this works then perhaps the product isn't for you. It is what it is. It is not a tube amp, it's the closest digital product available though. And I say this having compared every digital solution available. I've compared the 11R, KPA, HD500, etc. and the Axe-Fx comes closest to the real thing. The 11R with the right IRs can come pretty close (but you can't load IRs into it so it's an awkward solution) but I can still pick it out 80% of the time or more. In A/B tests I can pick the KPA out every time. It has a signature to the distortion and pick attack that varies greatly from the real amps. I have had no luck getting the HD500 to sound like the real amp.

No, no! The Axe IS FOR ME! Since 2009! I know most of the software modelers, i know the 11R - the KPA and HD500 not really well. Can`t really play with satisfaction all of these solutions over studio monitors when comparing it to the Axe. The Axe gives me the most Tube-Amplifier feeling and under recording circumstances it is really on par - no question! My opinion to the 11R is by the way much less good, than what i`ve read from you to that product ;) It is nice, but it every time i tried it (at friends homes) i noticed with the first chord, that their is this "modeler static thingy". Better than others, but immediately noticable - to me.

So: Yes - this product is for me, but i am really on the search how to get this "feel" out of the box, what i get, when i play it through a tube amplifer.

I would be really interested how and with which Amp / Speaker Cabinet you compare A/B to your actual Amps ... Still your 4x12" Mesa and the old, trusty ... what was it? Crown? Amplifer?

Man, i`m going crazy, this is really the LAST thing i miss ... i should achieve that ... perhaps a Tube-Power Amp is after all the right thing to me? But i won`t the coloration and the weight of them ;(
 
It varies. Usually a Carvin F1200. Sometimes a Matrix or a Crown.

Ahh ;) The Carvin was it. And did you think compared to the Matrix the differences (mostly in feel, whats coming out of the Guitar Cabinet !!!!!) are worth to point out? Or are the differences more ... "hmm, i have to double check which amp i am actual plugged in.." "nit picking" differences?
 
I found a schematic for a Studiotone. It is NOTHING like a JTM45 or any Marshall for that matter. It is a Class-A amp with no negative feedback. Therefore it will have substantial bass and treble boost. See my post about negative feedback in the Cliff's Notes forum.

I'm not at my development machine at the moment so I don't know what amp would be closest to this.
 
The OP is talking about the amp in the room sound right? Well that's the thing... there is no transparent FRFR power amp yet. There simply isn't. The power amp affects many things in the guitar tone. The closest I've gotten is simply using the real power amps of the heads that I've had. That's the only solution. You can hype Matrix all you want but it's not able to sound like a Mesa power amp and a Marshall power amp at the same time. It is not that transparent. I will have a Matrix at my rehearsal space in the next month so I can demonstrate this. Real cabs are so 1940. Time to enter the present time and stop using them.

i think Cliff's latest breakthrough in the newest beta might address what you are talking about.

This is the same blah-blah people have been throwing as a cure since Axe-Fx Standard: "the newest firmware feels so much better, now you can set your real amps to fire" :) No offence intended but I did get a natural "ahh cmon man" -face while reading your post. :)
 
I found a schematic for a Studiotone. It is NOTHING like a JTM45 or any Marshall for that matter. It is a Class-A amp with no negative feedback. Therefore it will have substantial bass and treble boost. See my post about negative feedback in the Cliff's Notes forum.

I'm not at my development machine at the moment so I don't know what amp would be closest to this.

Yeah it is EL84 based, so it mitght come to mind it would be more directed in the VOX / Macthless area. But it sounds nothing like that. Sadly i have not the experiences with so much and different real Amps, but the Clean channel is full and warm more like one of the princetone sims in the Axe or my very loved JM45 Sim and the Gain channel sounds to me really more to the Plexi100 in the Axe. When pulled down the bright switch and compensate with the treble knob you can get a bit in the "dumbleesque" territory. A BIT...(!)

I should add that it's an interesting design. I'll look into modeling it. It's definitely unique. The preamp is somewhat Marshally but the power amp is more like a Vox.

Nothing against that ;) Would be awesome to find my only real Amp modelled in the Axe! The idea that it would be worth to be modeled does never come to my mind, as i said, i have not this experienced background to so many real Amps - all i can say is: These Koch Amps sounded really good to me...
 
I just don't think this is a fair comparison. Like Cliff mentioned, the AxeFX-II is not a tube amp. You'll never hear the tubes pop, smell the heat from the glass, or capture that distortion that a tube amp produces.

There is a reason tube amps sound the way they do and are used on thousands of recordings. With that said, I would never be able to afford a Diezel, old Fender twin, etc., etc. The fact that I can "ape" a bunch of amps in my basement and pretend I'm Jimmy Page, makes my loins perk up.
 
The OP is talking about the amp in the room sound right? Well that's the thing... there is no transparent FRFR power amp yet. There simply isn't. The power amp affects many things in the guitar tone. The closest I've gotten is simply using the real power amps of the heads that I've had. That's the only solution. You can hype Matrix all you want but it's not able to sound like a Mesa power amp and a Marshall power amp at the same time. It is not that transparent.

Yes, this is the singular, specific thing that teases me: The translation of feel in the room through guitar cabinets. I did not exactly what you mean with "transparent" - i did NOT mean that frequency (EQ) wise. Frequency wise the Matrix satisfied me.

I thought the coloration frequency wise and in view to dynamics of the PowerAmp will be accurate enough (enough = we`re talking about placebo effects or nit picking differences i read a lot in the past in different threads, when it comes down to for example discussions with AB Audio files Cliff post ...) modeled from the Axe. And i am really still confident, that this will be so. Otherwise i have to believe Cliff and a lot of other people must be liars. So, i assume the modeling itself is not MY point.

So, IMHO a Matrix GT1000 or any other Solid state solution must not do the Marshall AND Mesa AND whatever PowerAmp trick - that`s the job of the Axe-Fx, no?! That said, i`ve made the last days the experience (again, but know i spent a lot of hours to confirm my impression with ABings), that a real Tube PowerAmp brings something to the table trough a real Guitar Cabinet, what i can`t achieve with solid state technology. And the question to myself is now: Play my mind tricks on me (what i not believe)?, is it a issue of Tube PowerAmp <-> Guitar Cabinet interaction what the Matrix shouldn`t do, because the Axes speaker tab is there to simulate this issue - knowing, that this is the singular point, the Axe has to assume, because of physical limitations. And because of that, there are the parameteres i have to tweak to get, what i feeled when using a Tube Amp? Or is the whole assumption i´ve made after my own experiences with those testings are invalid, because i compare apples to oranges? Or is it after all the wrong power amp for me? A Amp, 99% of users a find really useful and a great match?

So these are my questions resulting now in this thread asking people who have perhaps really an actual real amp of an Axe-Sim and have compared those real amps to the Axe + PowerAmp XY through the same speaker and can make a statement, what the primarily think, when it comes up to "feel". Soundwise (frequency wise) i have no issues ... ;)

So if now some people will say: Yeah, i have done those comparision and i really don`t know, what you`re taking about - the Axe-Sim+PowerAmp XY feels and sounds to me at least very, very identical to the actual Amp through the same cab in the same room - like Cliff did ... i would say: OK ... It is there ... you`ll have to find that out for yourself what to do to get it ...


If we say: When i play my recto sim through the fx return of my real recto and compare this to the real amp and it sounds and feels (almost) identical i assume, you set the PowerAmp Sim on the Axe Off, logical wise?

And if we put the PowerAmp Sim ON and play through a different PowerAmp and it feels NOTICABLE (unsatisfying) different, than it is something in the PowerAmp Sim / Speaker Tab and/OR with the used PowerAmp. OR the calibration of the powerAmp Sim incl. speaker Tab TO the used Poweramp to match the real recto poweramp, right? There come no more other parameters to my mind, where to search for ...

I really believe in the authenticity and quality of the Axe - no question. And so, i wnat to figure out, what i can do, to come to a result like for example ... Cliff.

I will try and research on ... but at the moment i think, it is a question of the used PowerAmp in relation with some parameters in the PowerAmp Sim, specially on the speaker Tab page.
 
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I should add that it's an interesting design. I'll look into modeling it. It's definitely unique. The preamp is somewhat Marshally but the power amp is more like a Vox.

Koch amps (such as the Studiotone) are probably the most famous "Dutch" amps. I owned a Multitone. I hate their signature tone. Clinical, harsh.

Hook amplifiers, also from The Netherlands, are much much better. Great designs. Great tone.
 
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My first advice is to turn Damping to zero. The Koch preamp is somewhat Marshally. It has a Marshall tone stack. The power amp, however, is more like a Vox. Turn Damping to zero and Hi Cut to zero. Turn MV way up to start as Vox power amps clip easily.

Using a model that has a negative feedback power amp is simply not going to the sound or feel the same as a model that has no negative feedback.

I still think this is more a case of apples-and-oranges than anything else. You are comparing a model that is very different to the actual amp and hence will have huge differences in frequency response, and I mean huge as in many dB. Our ears are more sensitive to frequency response than anything else. This is basic human physiology. Our ears are primarily FFT analyzers and understand frequency response more than any other auditory metric. I read all kinds of theories from guitar players on what they think they are hearing and yet what they really are hearing is simply a frequency response difference.
 
(...)but the Clean channel is full and warm(...)

Koch amps (Studiotone) are probably the most famous "Dutch" amps. I hate their signature tone. Clinical, harsh.

What i always say (as a forum owner ...): Don`t believe anything you read on forums ... :mrgreen:mrgreen:mrgreen

But please, ... back to topic ... where are the guys with the A/B comparisons Axe-Fx vs. actual Amp through the same Guitar Cabinet? ;)
 
I found a schematic for a Studiotone. It is NOTHING like a JTM45 or any Marshall for that matter. It is a Class-A amp with no negative feedback. Therefore it will have substantial bass and treble boost. See my post about negative feedback in the Cliff's Notes forum.

I'm not at my development machine at the moment so I don't know what amp would be closest to this.
Dolf Koch is a character all right.

His amps are indeed unique and opinions on them vary wildly. I'm not too fond of the ones I tried, although I used to play with a guy that had a Multitone that sounded pretty good on clean and rhythm. He never used the lead tone.
Hook amps are very good I've heard, but aren't they mostly Marshall clones? They look like that...
 
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