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The ethics of Kemper profiling amps

Hey, if anyone around the Central Fla area has an Axe-FX and wants to do a direct comparo with my Heritage rig, I'm game.
If I'm ever down your neck of the woods, I'd LOVE to bring along my buddy's Kemper and get profiles of your Heritage, V4B, B15:D. The profile on a Kemper is absolutely dependent upon how you set up the micing, EQ, etc., just like if you were recording it for the studio.
I actually record using a Kemper B15 profile. It's a great profile and must have been done by someone who knew what they were doing.
One of these days I'm going to profile my 20T through a 210AV. Would be interesting to see how that differs from just using the Trans DI! The cab would add some nice extra flavor I think.
 
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Haven't read the whole thread, but what's all the fuss about with these "profiles"?
If the profiles consists of an impulse response of a cabinet then that is just that, a snapshot of that particular "situation" (loudspeaker + environment + mic/angle/distance). What's missing from the picture is the response under different angles, distortion profile of the loudspeaker under several SPL levels, etc.
And on what system are you going to reproduce the "profile"? There's zero chance it'll sound and behave the same as the original loudspeaker, only a rough approximation.
Just my 2 cents.
 
Haven't read the whole thread, but what's all the fuss about with these "profiles"?
If the profiles consists of an impulse response of a cabinet then that is just that, a snapshot of that particular "situation" (loudspeaker + environment + mic/angle/distance). What's missing from the picture is the response under different angles, distortion profile of the loudspeaker under several SPL levels, etc.
And on what system are you going to reproduce the "profile"? There's zero chance it'll sound and behave the same as the original loudspeaker, only a rough approximation.
Just my 2 cents.
Perhaps you should take a couple of minutes and read more of the thread.
Profiles, and especially modelers, do not just consist of IRs of a cabinet / signal chain. Especially with modelers, which strive to precisely reproduce what the physical amp is doing. A lot of resources have been put down to do that, and we're really starting to get places with it. As picky as some bassists claim to be with tone and how tube amps play/react, guitarists are FAR more exacting about it, and many are impressed with how the top tier modelers are getting things nailed down.

All of those things you claim are missing? Nope, not missing.
What's discouraging? For large gigs, isn't that how you get your B15 sound to the FOH?
hehe, don't bring logic here ;)

Oh, the Tone Match function just creates an IR? Whoops. I read that as though it created a more complex profile, similar to the process used by the Kemper. Of course, a profile is not a complete amp model; more like a snapshot of a static state.
IRs are of cabs only. Fractal Audio products use modeling for amps and FX. You could actually even create an amp that doesn't exist entirely. I think this is likely the next chapter with modeling. A lot of people have bad misconceptions of what modeling and profiling are... which, in part is due to Line6's short comings (and over promising) over the years.

Slightly off topic but remember back in the 80's when nearly every amp manufacturer advertised a SS amp that "sounded exactly like tubes"?
Of course most sounded and responded nothing like tubes and the obvious answer was. "if you wanted to sound like a brand X tube amp, just buy one".

The way I see it is the modeling amps may be able to make a really good copycat tone
Can you modify a modeled sound into a new original sound?

IMO, even the biggest bands use one or maybe two different amps to generate tone
Other than studio or plays, would one really want to have 5 different amp tones for live use?
Seems like a band would no longer have their own unique, signature sound
.02
I was barely alive in the 80s, so I don't recall that at all :D
No offence meant, but this thread is packed full of people with zero experience or real knowledge of what the cutting edge systems are doing, and it shows. I understand though - for a long time, big promises were made and never at all met. I'll stick with the guitar forumites who are gobbling these things up and loving them, just as much as I am. Y'all can stick with your physical amps :D

Yes, a modeled sound can be drastically changed. Want an SVT with EL84 output tubes? Sure, switch the output tube model and you're done. Want to run a variac? Cool, set a new input voltage and you're done. Want to change the power supply sag to change the feel? Super simple to do!

I use 6 different amps for one band, and 4 different amps for another band - 10 total amps. I also run various settings on my effect pedal models, and different pedals all together in different presets. If I want to change my amp, cab, and pedalboard entirely, all I have to do is push one button and I have a new amp, a new cab, and a new series of effects with whatever settings I choose. All I have to carry to gigs for all of that? A 4U rack. Plus, I can get away with stuff that you just can't, or at least not cheaply/easily, in physical settings. I run 3 parallel signal paths with various branching and merging. I can't even imagine how much it'd cost to try to replicate one of my presets with physical hardware.

I don't follow on how a band can't have their own unique sound. If anything, I find it a heck of a lot easier to dial in things to exactly how I want - whether it be something well established, or something entirely new out of the box. When I can have any amp, with any cab, with any set of effects, how am I limiting myself? If anything, having the limitations of physical amps, cabs and pedals makes you sound more the same.
 
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With all of that said, modelers and profilers are obviously not for everyone. You have to have a certain level of technical knowledge and needs/wants. If you get away with a bass, a cable, a head and a cab... maybe a few FX pedals? Cool. Stick with it, that works. Nothing wrong with it.
 
Haven't read the whole thread, but what's all the fuss about with these "profiles"?
If the profiles consists of an impulse response of a cabinet then that is just that, a snapshot of that particular "situation" (loudspeaker + environment + mic/angle/distance). What's missing from the picture is the response under different angles, distortion profile of the loudspeaker under several SPL levels, etc.
And on what system are you going to reproduce the "profile"? There's zero chance it'll sound and behave the same as the original loudspeaker, only a rough approximation.
Just my 2 cents.

The fuss is actually about profiles of amps -- not speakers/cabs. Profilers are being used to mimic amps. These profiles can then be used with IRs of cabs, but the talk is really around profiling of the amps.

People run it different ways. Some amplify the signal and connect to guitar cabs. Some connect to PAs and studio monitors and (typically using cab IRs).

Yes, it is not capturing all the variables of the equation (you mentioned mic position) and a profile focuses on a static state of an amp (ie mimics it as it is dialed in when profiled). Modern profilers and modelers sound quite good, but no, they won't give you all the control/variables and idiosyncrasies of the real thing. That is a blessing and a curse.
 
Yes, it is not capturing all the variables of the equation (you mentioned mic position) and a profile focuses on a static state of an amp (ie mimics it as it is dialed in when profiled). Modern profilers and modelers sound quite good, but no, they won't give you all the control/variables and idiosyncrasies of the real thing. That is a blessing and a curse.
I am sure this will come off rude, but I don't know how else to say it.
Where are you getting all of this information? Because, frankly, it's pretty incorrect. It's one thing to say that you think/feel/believe they don't sound good - that I can get behind, as everyone has their preferences. But to say that "they won't give you all the controls/variables" etc., is well, wrong. Using your mic position example... yup, you can absolutely set mic position in some of these. You can combine mics, just use multiple mics, use mics on different speakers, use different speakers in the same cab and on and on.
 
What's discouraging? For large gigs, isn't that how you get your B15 sound to the FOH?
That's one way to do it. You can also run a speaker level DI. But traditionally, there's an aspect of the tone that's missing when you use reproductions vs hearing the real thing. Not saying it's not usable by any means...but this is what has kept me using the real thing.
 
I am sure this will come off rude, but I don't know how else to say it.
Where are you getting all of this information? Because, frankly, it's pretty incorrect.

Oh?

It's one thing to say that you think/feel/believe they don't sound good…

Citation needed.

yup, you can absolutely set mic position in some of these. You can combine mics, just use multiple mics, use mics on different speakers, use different speakers in the same cab and on and on.

The software allows you to combine IRs and do things like process/delay/mix those IRs but you're a fool if you think you have identical capability to a bunch of cabs, a closet full of mics, and real rooms -- in the extent available in the real world. The IR will capture the sound at a specific point in space within a room and an exact signal chain and reproduce it perfectly (assuming it's done correctly). Take step back from a cab, rotate the mic, or bring it closer to the floor and you'll need a new IR to reproduce that perfectly. Adding 1 ms of delay in software to the first IR is not the same as taking a step back. There are reflections in the room. Acoustics, time, and space are big contributors. Your Axe-Fx does not have room for all the IRs required to represent all positions in a room comprehensively. Fortunately you don't need that many IRs to get a good sound. Now, change the mic and you'll need a new IR to represent that speaker, cab, mic position, mic, and room perfectly. Directional mics respond differently as you move them on and off axis. Your virtual mic locker + Room/Cab IRs does not represent all possible positions/configuration available in the real world.

Effectively, you have most - not all - of the ingredients a recipe calls for. Some ingredients are omitted. Some ingredients are substituted. Some ingredients just aren't used in the amount called for by the recipe. The result is still lasagne/whatever, but it is slightly different from the original.

Blending/layering/filtering/mixing of IRs in this manner is an approximation of the real thing. Sometimes it works, sometimes it's nasty. Many people can live with that approximation and - here's the important part - get usable sounds. I'm not saying you don't have any variables/parameters -- I'm only saying you have some of the variables present in the real world and some of the ways these are presented to you compromise the accuracy and flexibility of real amps in real rooms with real mics. Also, several of these "variables" have reduced a reduced set of possible useful "values" compared to the real world. That said, an Axe-Fx is capable of sounds/configs real amps can't touch.

Analogy: Take a photo of somebody in a room. Change the perspective by taking one step to the left and take a second photo. The photo is not identical. Maybe you don't care because you can still identify the individual in the photo. I'm just pointing out that the two are not identical.

Sure, IRs can be combined, but the software/creators stop short of comprehensive and accurate (because it is impractical), introduce some conveniences/approximations for you and that gives you several parameters to work with. It's close, but not perfectly accurate while giving you all the variables available in the real world.

So go ahead and explain - how exactly is this incorrect?
 
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It's incorrect because of how Fractal Audio handles mics.
The mic is its own IR. Then the cab IR is its own as well. You can position the mic in proximity to the cab. You can change the mic IR used. You can use multiple cab or mic IRs.

You asked for citation - read through the Axe-Fx Wiki and the official user documentation, which details all of this, with input from Cliff (main guy @ FAS) on how these things work in the real world and mathematically.

It really sounds like you have the idea that they take, essentially, a recording of the signal chain and that is it. Even the Kemper profiler, which does that as a basis (versus algorithms of Axe-fx), is not so limited.

Sure, there are essentially infinite cab/mic position combinations in the real world. Gig to gig you don't even have the same one. I don't expect a modeler/profiler to give me free reign over placement. The vast majority of the time, the mic placement is pretty universal at gigs and in the studio. Wonky things can be done for interesting sound or texture, but you can accomplish the same with other means.

Now, your turn to answer my original question and one other; which modern modeler/profiler have you used beyond 15 minutes at a store?
 
That's one way to do it. You can also run a speaker level DI. But traditionally, there's an aspect of the tone that's missing when you use reproductions vs hearing the real thing. Not saying it's not usable by any means...but this is what has kept me using the real thing.
Your standard methods are my standard methods, and I'm not disagreeing that a cab mic or speaker-level DI can crush.

But once you scale up in FOH, it's *all* reproductions. For example, my personal taste greatly prefers Two Notes cab emulation to a Redbox speaker-level DI, b/c even the C.A.B. entry-level emulation sounds better (more "real" if you'd prefer, as long as we keep the ironic quotation marks) than the H&K Redbox. Some types of reproduction are more mature technologies than others (and it feels like emulation has not nearly plateaued yet), but even at this fairly early stage I can't go along with categorically calling any speaker level DI more real than every hardware/software emulation. Nor would I always automatically prefer a cab mic. The house of cab mics has many rooms; and while some of them are glorious, some of them are dumps—and none of them suits all needs
 
Haven't read the whole thread, but what's all the fuss about with these "profiles"?
If the profiles consists of an impulse response of a cabinet then that is just that, a snapshot of that particular "situation" (loudspeaker + environment + mic/angle/distance). What's missing from the picture is the response under different angles, distortion profile of the loudspeaker under several SPL levels, etc.
And on what system are you going to reproduce the "profile"? There's zero chance it'll sound and behave the same as the original loudspeaker, only a rough approximation.
Just my 2 cents.

You should really look an try some out, since demo versions are free. IK Amplitube is a good one to try. Cabinet impulse response, convolution reverb is used for the cabinet part.

You can select the Cabinet, the Mic, a couple of Mics, the positions, how far back, and the room. All the position, the distortion, under several SPL levels are accounted for in some of the IRs. It's not just filters like old cab sims were.
It sounds like a studio mic'ed cabinet.
 
On the "What came first" The first tube amps didn't distort so well. There wasn't that much gain. There was no "Master". Old blues players would razor slash their speakers to add distortion. The fuzz box came in the 60's. That is SS fuzz boxes that could run off batteries. These are essentially high gain overdriven SS amps. SS amp makers started building in Fuzz boxes. Later tube amp makers started to build higher gain multistage pre-amps so players wouldn't need fuzz boxes. No matter what your view of what's first and best, modeling/profiling is capturing all of it and creating new sounds for players who want to search for it.
 
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Your standard methods are my standard methods, and I'm not disagreeing that a cab mic or speaker-level DI can crush.

But once you scale up in FOH, it's *all* reproductions. For example, my personal taste greatly prefers Two Notes cab emulation to a Redbox speaker-level DI, b/c even the C.A.B. entry-level emulation sounds better (more "real" if you'd prefer, as long as we keep the ironic quotation marks) than the H&K Redbox. Some types of reproduction are more mature technologies than others (and it feels like emulation has not nearly plateaued yet), but even at this fairly early stage I can't go along with categorically calling any speaker level DI more real than every hardware/software emulation. Nor would I always automatically prefer a cab mic. The house of cab mics has many rooms; and while some of them are glorious, some of them are dumps—and none of them suits all needs
Red Box is only good for guitar. I used to have one (unfortunately it got stolen out of my house at a party...hence, no more parties here ever) and it was unusable on bass. When I do speaker level, I use a Countryman Type 85.
 
It's incorrect because of how Fractal Audio handles mics.
The mic is its own IR. Then the cab IR is its own as well. You can position the mic in proximity to the cab. You can change the mic IR used. You can use multiple cab or mic IRs.

Oh, I understand what's going on well enough. You didn't read/understand my response -- or my english is just not good today.

See my recipe analogy. Axe-Fx combines IRs of the primary stages involved. Stage by stage. This approach doesn't capture an entire system -- including all the reactions within that system. Therefore, it does not perfectly reproduce a real system. It is merely a simulation which samples the most important parts. Furthermore, breaking the stages apart offers user control at the expense of accuracy because the lack of comprehensive IRs results in software approximating (using an IR as a starting point) -- see that bit I wrote about moving a mic a foot back is not identical to a 1ms delay. The reason this compromise was introduced is because it would be an enormous undertaking to create such a comprehensive IR library. Like VSL size :roflmao: So maybe you don't care about 5% error here, 5% error there -- but that error does accumulate and affects the accuracy of the ability for the software to reproduce everything it parameterizes perfectly.

Get a cab in a room and the sound is bouncing off walls and a mic at a specific angle -- there is a reaction between all those elements. It cannot be reduced to a serial sequence of effects -- or a composite IR of 3 stages.

You asked for citation - read through the Axe-Fx Wiki…

I said "Citation needed" in response to you writing: "It's one thing to say that you think/feel/believe they don't sound good…". Meaning, where exactly did I say that? Quote me.

My english must be very bad today.

It really sounds like you have the idea that they take, essentially, a recording of the signal chain and that is it. Even the Kemper profiler, which does that as a basis (versus algorithms of Axe-fx), is not so limited.

Wrong.

Now, your turn to answer my original question and one other; which modern modeler/profiler have you used beyond 15 minutes at a store?

I "get my information" from having written audio and music software for fun and profit for many years. I know much of what's possible for processors and recognize compromises developers must make and how those "tweaks to the formula" introduce error. I'm not making my identity public, so don't ask further.

I've used many and have licenses for several, but I don't own an Axe-Fx or Kemper. I was using modelers onstage and in the studio before it was cool :thumbsup: My real amps get used almost daily, the hardware sims are collecting dust, and the software ones get occasional use -- these days.
 
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Cool. So you have no direct experience with what we're actually discussing. Good to know. Are you saying that Axe-Fx is an IR of the amp? Because... it's not. The only IRs present are the cab and mic.

I don't think anyone is claiming that these products will be able to recreate every last possible, thinkable combination of everything, perfectly. Even two amps are not identical, so what your arguing is impossible in any space. What they do - model/profile amps, cabs and FX - they do amazingly well. Live I doubt anyone would notice any difference between the high end model and the physical amp. Recording, someone may say "Well your Marshall widget doesn't sound like mine", which is fine, tone is subjective. For me, I could not hear a discernible difference between the modeled SVT and my SVT-CL - live or recorded. If I still had either SVT, I'd post some recordings to see who can sucessfully identify one over the other. I doubt anyone could repeatedly.
 
Cool. So you have no direct experience with what we're actually discussing. Good to know. Are you saying that Axe-Fx is an IR of the amp? Because... it's not. The only IRs present are the cab and mic.

I don't think anyone is claiming that these products will be able to recreate every last possible, thinkable combination of everything, perfectly. Even two amps are not identical, so what your arguing is impossible in any space. What they do - model/profile amps, cabs and FX - they do amazingly well. Live I doubt anyone would notice any difference between the high end model and the physical amp. Recording, someone may say "Well your Marshall widget doesn't sound like mine", which is fine, tone is subjective. For me, I could not hear a discernible difference between the modeled SVT and my SVT-CL - live or recorded. If I still had either SVT, I'd post some recordings to see who can sucessfully identify one over the other. I doubt anyone could repeatedly.
Which brings us full circle to my point about digital modeling sounding like recordings :D
 
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