• We would like to remind our members that this is a privately owned, run and supported forum. You are here at the invitation and discretion of the owners. As such, rules and standards of conduct will be applied that help keep this forum functioning as the owners desire. These include, but are not limited to, removing content and even access to the forum.

    Please give yourself a refresher on the forum rules you agreed to follow when you signed up.

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

Morphosis

Fractal Fanatic
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.
Allright. I much appreciate your "helping hands" and your suggestions! Thank you! I will try these out also checking the beta5 and some different sims and give the other power amp i still have a try again... My goal is really not to match my Koch, but the likely depth and feel i get out of it in relation to the guitar cabinet. As i said and you are right, i really can`t exclude that it is really a apple to orange thing. I will take a further look into this ...


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.
Yep, this is a problem and surely includes me. When i boosted (increase) the Lo- and Hi Res in the speaker tab i thought it goes into the right direction - in fact this result in also in a difference frequency response ... otherwise i thought, yes .. a bit, but there is something else missing going on, i really will triple check tomorrow and try your suggestions and some ideas coming the last hours to my mind ...

Perhaps it happen and i will find a few firmwares later my Studiotone in the Axe ... would be perhaps helpful to understand some things more or better .. ;)

@YEK: Clinical? Harsh? ... Meh .... ;)
 

BillyZeppa

Power User
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 will try this. I have a Mesa MarkIII with 'simul-class' power amp -> open back cab 1X12 Black Shadow. I can run this either 15Watt Class A on EL35s, or 60Watt Class AB on 6L6s, so i can try both ways. Which i will do just as soon as i can get my Axe FX II.
 

Morphosis

Fractal Fanatic
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.
+

(...)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. (...)and yet what they really are hearing is simply a frequency response difference.
Allright: The plan for tomorrow:

1) Finding two Amp-sims tomorrow where i come in the "ballpark" with the damping/MV&Hi Cut suggestions, perhaps try a Marshall tonestack - target: Bring the Axe+SS Poweramp into the ballpark of the Koch

2) Then Tonematching this pre-tewaked Axe-Sim to the Koch to come closer frequency wise and

3) Compare the whole Koch (Preamp+PowerAmp) again with what will come out through the Axe with the Solid state Amp ...

If this will not work, i try different a PowerAmp and search for any other Sims i feel good with ... and try to get them to satisfaction ;)
 

FractalAudio

Administrator
Fractal Audio Systems
Moderator
The Studiotone has a line out from the power amp. This is perfect for doing a real-time Tone Match. As follows:

1. Connect that line out to Input 2 Left.
2. Connect Output 2 Left to the input to the amp. Turn Output 2 Level all the way up.
3. Make sure you have beta 5 fw installed. Set Output 2 Echo to Input.
4. Make a preset that is simply amp->tma. Set the TMA block mode to RealTime. Set the time to 15 seconds or so.
5. Go to the first page in the TMA block and press the Up arrow. Play some chords for 10-20 seconds. Press Enter.

This will show you just have different the frequency response is. I bet you'll be surprised.
 

jlynnb1

Fractal Fanatic
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. 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. :)
If Cliff figured something about preamp/power amp interaction that had a marked affect on the feel/response of an amp....I don't see how you have a point. But feel free to roll your eyes til your heart is content.
 

Morphosis

Fractal Fanatic
The Studiotone has a line out from the power amp. This is perfect for doing a real-time Tone Match. As follows:

1. Connect that line out to Input 2 Left.
2. Connect Output 2 Left to the input to the amp. Turn Output 2 Level all the way up.
3. Make sure you have beta 5 fw installed. Set Output 2 Echo to Input.
4. Make a preset that is simply amp->tma. Set the TMA block mode to RealTime. Set the time to 15 seconds or so.
5. Go to the first page in the TMA block and press the Up arrow. Play some chords for 10-20 seconds. Press Enter.

This will show you just have different the frequency response is. I bet you'll be surprised.
That`s what i`ve done with FW6, but using the recording out i believe:
If you hear Noise -> it`s the Koch. If you don`t -> It`s the AXE-FX II (SLO100)

(Matched with Sine-Sweep from SYNTH Block (connected freq. to LFO!)
If you hear Noise -> it`s the Koch. If you don`t -> It`s the AXE-FX II (SLO100)
Played with a Strat in SC and HB mode. Clean - Gain only by using the Volume poti from the strat. NO post-editing! (Only normalized zo -0.3db and dither from 24bit to 16bit while extracting to MP3)


So, this was the result a year ago and i was more than happy with it! But as i said, this is the "recording / studio environment", not the "live in the room feel" experience.

I`ll do that tomorrow with the Line Out, using the the real cabinet as Speaker for comparison on both chains.

Also i prefered until today the sine-sweep from synth, but leveling it`s output to the "naked" guitar signal output is a bit difficult. So thanks for pointed out:

3. Make sure you have beta 5 fw installed. Set Output 2 Echo to Input.
Man, i have to thought about a minute why Echoing Input to Output2 - Yeah doing it with the guitar as measurement-signal the FX Loop block is not needed anymore! COOL! Makes live simplier ;) Never thought about THAT!

Question: Should i match with attached Cab to the Koch or should i take the inbuilt Power Soak when matching? Asking because of perhaps different frequency response because of the resistance (Cab vs. Power Soak?) Or does that not matter? I think the most accurate result should be, when the poweramp can react with the Guitar Cabinet when matching the Line Out simultaneously?

I´m looking forward to the result i will get! Will keep this thread updated when the work is done ;)
 
Last edited:

FractalAudio

Administrator
Fractal Audio Systems
Moderator
Morphosis;969182 [B said:
Question:[/B] Should i match with attached Cab to the Koch or should i take the inbuilt Power Soak when matching? Asking because of perhaps different frequency response because of the resistance (Cab vs. Power Soak?) Or does that not matter? I think the most accurate result should be, when the poweramp can react with the Guitar Cabinet when matching?
Use the cab. Do not use the built-in power soak. The schematic shows a line out that is tapped off the speaker outputs. This is perfect for tone matching.
 

FractalAudio

Administrator
Fractal Audio Systems
Moderator
BTW, I do this whenever I model an amp. I have a load box that has a line out. I don't use the load part of it, I just use it to convert the speaker output to line level.
 

Morphosis

Fractal Fanatic
BTW, I do this whenever I model an amp. I have a load box that has a line out. I don't use the load part of it, I just use it to convert the speaker output to line level.
This is very interesting, at least, because i asked myself under which circumstances you model the amps. So when modeling or measure you connect a convenient Guitar Cabinet as load to the amp, this load (guitar cabinet) could also be the draft for the speaker tab impedance curve (or resonance?!) settings and so all the "current feedback" interactions between PowerAmp and Cab will be considered when modeling and measurements?
 

Jeff B

Inspired
The Studiotone has a line out from the power amp. This is perfect for doing a real-time Tone Match. As follows:

1. Connect that line out to Input 2 Left.
2. Connect Output 2 Left to the input to the amp. Turn Output 2 Level all the way up.
3. Make sure you have beta 5 fw installed. Set Output 2 Echo to Input.
4. Make a preset that is simply amp->tma. Set the TMA block mode to RealTime. Set the time to 15 seconds or so.
5. Go to the first page in the TMA block and press the Up arrow. Play some chords for 10-20 seconds. Press Enter.

This will show you just have different the frequency response is. I bet you'll be surprised.
Hi Cliff. I was just reading through and noticed this post and wanted to ask you if you could help guide me on tone matching my Peavey JSX.

I have a line out on the rear of my amp and want to know if I can use that as an input to the AFX. Also, the EQ is an active circuit which is different than a lot of other amps, I think. Can I simulate that in the amp block at all?

If you could help outline the connections and maybe what amp you feel would be the best to begin with, how I should build my signal chain and and specific adjustments I should make to best mimic the EQ, I'd appreciate it. I figure these are simple things for you since you know the AFX inside out. Thanks!!
 

FractalAudio

Administrator
Fractal Audio Systems
Moderator
This is very interesting, at least, because i asked myself under which circumstances you model the amps. So when modeling or measure you connect a convenient Guitar Cabinet as load to the amp, this load (guitar cabinet) could also be the draft for the speaker tab impedance curve (or resonance?!) settings and so all the "current feedback" interactions between PowerAmp and Cab will be considered when modeling and measurements?
Yes.

There is no current feedback in a typical guitar tube amp. It is voltage feedback. Your Koch has no feedback.
 

Morphosis

Fractal Fanatic
Hi Cliff. I was just reading through and noticed this post and wanted to ask you if you could help guide me on tone matching my Peavey JSX.

I have a line out on the rear of my amp and want to know if I can use that as an input to the AFX. Also, the EQ is an active circuit which is different than a lot of other amps, I think. Can I simulate that in the amp block at all?

If you could help outline the connections and maybe what amp you feel would be the best to begin with, how I should build my signal chain and and specific adjustments I should make to best mimic the EQ, I'd appreciate it. I figure these are simple things for you since you know the AFX inside out. Thanks!!
Connections as Cliff posted. You can set the EQ in the Amp Block also to "active" (instead of passive). Do this BEFORE matching. If the Line Out is after the PowerAmp -> Perfect, same as with my Koch. If not (In fact it`s a preamp out) but you`ll will get the coloration of the JSX PowerAmp: Get Hands down to something like a Behringer GI-100 DI Box. With that you can loop the Guitar Cabinet through the Speaker Output and take the Line Out from the DI Box ... the same, like Cliff mentioned what He`s doing...
 

kmanick

Fractal Fanatic
I've had the opportunity to A/B 3 of the amp models against their real counterparts (well 4 actually)
I have had the Matrix Gt1000FX ,Art SLa2, the Carvin TS100 the Mesa 50/50, the Fryette 2/50/2 and the Marshall 9000 power amp.
when I initially bought the Matrix I loved it....until I A/b'ed against the Fryette. I noticed some the characteristics you mentioned
above were present with the Fryette and missing with the Matrix.
" 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. "

Exactly how I felt so I now go FRFR from out 1 and believe it or not into a JSX from out2 (works surprisingly well but that's another story)

Going into a regular 2X12 cab:
when I ran my mesa 50/50 with the mesa mark models everything was spot on, sound, feel etc. (Studio pre as well that was #4)
but all the other models sounded drastically different.
When I ran the Marshall 9000 with the JVM, the JMP-1 and the Friedman models, again they felt and sounded very authentic but all of the Non Marshall models suffered.

When I used the Fryette everything felt and sounded great but they were all just a bit "off" in sound, the feel was great but it was much more difficult to
nail the actual tone of the model (BTW I always leave power am modeling on unless I'm playing at gig volume ). Something was always Missing.
When we A/B'd the Jvm Model(9000 power amp) with the JVM head we actually liked the Model better (less fizzy , sharper sounding) feel was spot on.
When we A/B'ed the JMP-1 using the 9000, we couldn't tell them apart, really good job on this model.

I think what you're going to find is that to recapture some of that "magic" you're going to want a tube power amp, I really don't notice it playing chords but go into shred mode and
it really jumps out at me. the problem that I have found is that tube power amps will always lean in a certain direction.
If you're a Marshall type of guy, get a 9000, you'll be very happy, if you're a Mesa guy get a 2:90 (I like that power amp better than the 50/50).
If you need a wide range an don't mind everything being just a bit "off" grab a VHT or Fryette 2/50/2.(worked really well with the lower gain models and cleans BTW)
Going through exercise I've found that when going into a real guitar cab using the Axe FX II the Power amp makes a huge difference in your end result.

the JSX I'm using now is a rather Unique animal as it sounds somewhat Marshall-ish and somewhat Mesa -ish. I have been able to dial in pretty good patches using it
plus it's a very well behaved lower volume head , so I can opt to just use that stand alone if I like and use the Axe just for effects (which I often do)
 

Jeff B

Inspired
Connections as Cliff posted. You can set the EQ in the Amp Block also to "active" (instead of passive). Do this BEFORE matching. If the Line Out is after the PowerAmp -> Perfect, same as with my Koch. If not (In fact it`s a preamp out) but you`ll will get the coloration of the JSX PowerAmp: Get Hands down to something like a Behringer GI-100 DI Box. With that you can loop the Guitar Cabinet through the Speaker Output and take the Line Out from the DI Box ... the same, like Cliff mentioned what He`s doing...
The line out is definitely post-power amp, so if I take a line from that output and run it to the IN of the AFX, I can use that as the local signal in a tone match block?

I'm a bit confused as to your explanation of looping the guitar cab through the speaker out, etc.
 

Morphosis

Fractal Fanatic
The line out is definitely post-power amp, so if I take a line from that output and run it to the IN of the AFX, I can use that as the local signal in a tone match block?
Yes
I'm a bit confused as to your explanation of looping the guitar cab through the speaker out, etc.
The Cab is just to give the PowerAmp a load, it`s not in the signal chain when matching. So keep the cabinet at the Amp for load and just use the Line Out of the actual Amp for the match. In fact you`ll match the actual Head against the Amp Sim in the Axe.
 

Morphosis

Fractal Fanatic
Me too on both counts. Scott Peterson owned one too, IIRC. He's not a fan, either.
Twintone & Multitone are EL34 based Amps, the studiotone is a different beast. But when it comes to taste ... does not matter - whatever.

The direction of the thread went probably a bit out of it`s intended range, because using the PowerAmp of the Koch was to me just the example for a general difference beetween the feel solid State against tube. Cliff has given good points to me to rethink about frequency response issues and i will go there as written in detail, but i had wrote the OP exactly the same, just talking about a Reußenzehn Tube PowerAmp instead of the Koch PowerAmp.

I think kmanick got me right, when he state:

(...)when I initially bought the Matrix I loved it....until I A/b'ed against the Fryette. I noticed some the characteristics you mentioned above were present with the Fryette and missing with the Matrix.
" 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. "
Perhaps it is really more a frequency response thing as Cliff said - this would be the easiest traceable explanation. And if so, a added EQ to shape a bit the Matrix could do perhaps the trick. If all these things won`t do it - perhaps something like the VHT/Fryette thingy could bring me the actual missing satisfaction when it comes to driving a Guitar cabinet. I remember a lot of guys saying good things about those PowerAmps including the statement, that they would prefere these a little bit over the Matrix soundwise, but to little advantages to bit in the apple and carry those heavy Tube Amps all the way, instead to keep live simple and light with the smart Matrix. We`ll see... ;)
 
Top Bottom