Posts by ColdFrixion

    What I mean is, for example

    running 2 amps and cabs on the axe AND using the full amp profile together in stereo with the Kemper running into the effects loop of the axe.

    So, 3 amps and cabs total

    I virtually never use more than a single amp model with or without the Kemper in the loop, but my hunch is that the phase issue you're hearing when running a Kemper profile alongside one or more amps/cabs in the Axe is likely related to a timing discrepancy between the two signals, which is putting them slightly out of phase.

    Did you run amp sims in the axe at the same time as the Kemper into the axe loop?

    I'm not entirely clear on what you mean. I've used amp models in the Axe-Fx in conjunction with the Kemper's cab section via the Axe's FX loop, for example. I've also captured the Kemper's cab section using the Axe-Fx's built-in IR capture utility and compared an amp model in the Axe-Fx through the Kemper's cab section vs. the captured IR via the FX loop and couldn't hear a difference.

    I've been running the Kemper and the axe fx together past few days, sounds amazing af. But it seems the Kemper has a more phase filter sound/out of phase when running the axe fx either into the aux input or in an effects return/stereo loop (its less filter sounding lol). Running the Kemper into an effects return of the axe fx seems to be less of a problem but is still there a little bit. Any tools in the axe that you know of to fix this? Maybe its an advance amp setting? I've been diving deeper into those parameters so my navigation is getting a lot better.

    I'd have to hear an example. When I compared the KPA direct vs. the loop of the Axe I didn't hear a difference, but I may try the comparison again for confirmation.

    Yes.... all of the above. I find that MOST people who have used both consider the KPA easier to obtain a specific tone for a specific song on...... or to get a specific tone they have thought up in their head. Again, not saying the Axe doesn't let you get there, just takes more work and time.

    It really depends, in my opinion. If I want to duplicate a specific tone, the Tone Matching feature in the Axe-Fx is, on average, faster than profiling, in my experience. They're both equally fast when it comes to loading profiles/presets. If you understand some of the advanced parameters in the Axe-Fx, it can be faster to get from point A to point B in terms of tweaking, as there are a lot of very specific tools designed to produce very specific effects that aren't available in the Kemper, but again, I'm referring to someone who understands and knows their way around the advanced parameters in the Axe.

    I wonder if the Kemper team read these and laugh at how we try to explain this stuff...


    I've given up on trying to provide balance here, I'll leave that to others...

    I can't speak for anyone else, but my explanation regarding the phases of profiling was taken directly from the Kemper manual.

    To be honest I dont understand the concept of the fm3.

    The FM3 marketing doesn't specifically target gigging musicians, but I think the concept of the FM3 is simple. It offers the same quality of amp modeling, many of the same effects and the same number of stock IRs as their flagship model (ie. Axe-Fx III) at a more affordable price. Some users are primarily interested in the amp modeling and effects of the Axe-Fx III but can't afford it, and this represents a more affordable option.

    What it actually does (in layman's terms) is it figures out what an amp does by sending it a known signal, then measuring what comes out with a microphone). It is clever enough to do enough of a range of input situations that it digitally duplicates exactly (or very close) how ANY input would be processed into an output. To put it more simply it captures the soul of the amp.

    That's part of the three data collection phases that occurs during the profiling process. I'd recommend reading the reply I posted to Alfahdj in post #85 (above):


    "The Profiling process consists of data collection regarding the reference amp over three phases. The first phase involves generating white noise that's used to learn about the circuitry of the reference amp, the frequency response of the cabinet, and the characteristic impedance curve of the speaker, including its feedback to the power amp. The next phase involves using white noise to learn about the dynamic distortion curve of the tubes in the reference amp. The third phase involves sending a complex tonal texture to the reference amp that creates unique interference patterns that allow the Profiler to take a “fingerprint” of the DNA of the reference amp’s particular sound. After all of those measurements are taken and data collected, the Profiler uses that data to fill in the settings of a complex base model."


    A model is VERY different. A model attempts to put all the filters, circuits, etc, etc into mathematically equivalent make-ups like they are in the real amp. In theory, if you get all these pieces of the model right, you can not only capture the amp in a specific state (like Kemper does), but also know how it will behave when any piece of the amp is changed.

    You're referring to component level modeling, which is one type, but a model is simply defined as something that accurately resembles something else.


    Even the simplified GUI presented by the Axe is VERY complex and there are a metric s**t ton of settings that can be controlled. Actually understanding how much of these settings will effect a specific model is quite difficult.

    The Axe-Fx has an "Authentic" view which includes only the controls you'd find on a specific amp. If a user wants or needs greater control, there are more advanced parameters available, but they're not visible from the Authentic tab. There's generally no need for a typical user to access the advanced parameters, but an advanced user might enjoy getting into the nuts and bolts of an amp. The difference is, changing some of those parameters on a real amp would normally require a screw driver, and fortunately, the Axe-Fx provides a means to modify them without taking an amp apart.


    As I have already stated, it is my opinion after spending a good amount of time comparing the two that either unit can be a great gigging rig and will sound fantastic. It is also my opinion that the KPA is easier to get a great sound out of quickly. YMMV.

    In my opinion, it depends. In terms of turning the unit on, selecting a preset/profile and playing, they're both equally fast. It doesn't take me any longer to select a preset in the Axe-Fx than it does to select a profile in the Kemper, though the Axe-Fx III boots up faster. However, one could argue that creating a preset from scratch is often faster than creating a profile from scratch.

    If you follow the entire thread, posts

    The entire thread? The entire thread was a whopping 5 posts long before I replied, and 8 posts long before you chimed in.

    the main reason I commented at all was to supply additional background re: the BBE in order to clear up any misunderstandings implying that EQ was all the BBE had to offer.

    It's my post you originally replied to, and I never implied that the BBE is exclusively EQ based, nor did anyone else.

    Casual users who weren't familiar with the history of the box could easily think that, and I suspect my information was new to you as well.

    I had a nearly identical discussion on another forum two years ago about the BBE after posting my recipe for emulating the BBE's effect using a PEQ block in the Axe-Fx II. So, no new information here.

    So don't take it personally, this is how urban legends start - "You don't need a BBE, because any old EQ will do!"

    For my use case, any old PEQ would do just fine. In fact, for my use case, the BBE is nothing more than a glorified tone control.

    Addressing your "if you can't hear a difference, what difference does it make?" question, I believe I already answered that but the point is that woofers & tweeters can get smeared in time due to their crossover networks, leading the upper harmonics to detach from the lower fundamentals, taking away some of the impact or "punch" of the bass if you will. This problem is speaker & time dependent, it's not an EQ thing and it's more of a problem for PA designers & hi-fi enthusiasts perhaps but there you go. On some speakers, flat BBE will make your mix sound better in a subtly psychoacoustic way, whereas on others it may not matter.

    Firstly, I don't know anyone who actually uses the BBE with the controls set to 0. Secondly, depending on the playback system, if you think you can hear a difference that's not reproducible via EQ, then by all means, listen to the clips I posted on whatever playback system you believe will allow you to clearly hear the differences, and let me know which sample(s) are based on the BBE vs. EQ.

    a setting of 3.0 means that you've got some corrective EQ (Lo and/or Processing) going on so of course your EQ isn't flat.

    The frequency spectrum isn't flat with the controls set to 0, either.


    I'm going to say this again, so please peruse the following statements carefully: I never claimed EQ can emulate what the BBE is actually doing. I stated that EQ can emulate the effect it produces. The audible effect, which is the only thing I'm concerned with.


    If you can't hear a difference between the BBE and an EQ model of the audible effect it produces, what difference does it make?

    So again - obviously you can hear the Lo & Process EQ's, if they're being used - that's not up for debate. But if you leave the controls at minimum, the Maximizer effect is nearly inaudible from a EQ perspective.

    If the effect is nearly inaudible, that would mean it's audible to some degree, and if it's audible and demonstrably affecting the frequency response, which it is, then it wouldn't solely be phase oriented.

    "a sort of automated modeling" its him trying to put on simple words what the profiler does without start speaking about digital control algorithms and observable domain transfer funtions to a random press which is asking "what does your product do?". I am 99% sure kemper profiling technology is based into transfer function reproduction, and not modelling, 2 aproaches, as I explained, completely different from one another.


    Also I could quote the kemper guys telling again and again and again that this is not a modeler, but a profiler, and that adds up to their approach, Modeling, it isnt :D

    Christoph clearly explained what he meant by "a sort of automated modeling". He used the word model twice in that explanation. Again, the Profiling process consists of data collection regarding the reference amp over three phases. The first phase involves generating white noise that's used to learn about the circuitry of the reference amp, the frequency response of the cabinet, and the characteristic impedance curve of the speaker, including its feedback to the power amp. The next phase involves using white noise to learn about the dynamic distortion curve of the tubes in the reference amp. The third phase involves sending a complex tonal texture to the reference amp that creates unique interference patterns that allow the Profiler to take a “fingerprint” of the DNA of the reference amp’s particular sound. After all of those measurements are taken and data collected, the Profiler uses that data to fill in the settings of a complex base model.


    I could quote the kemper guys telling again and again and again that this is not a modeler, but a profiler, and that adds up to their approach, Modeling,

    I posted a direct quote from Christoph Kemper in which he clearly states that the Kemper uses "a very complex base model of a generic guitar amp". He then states that with the settings filled in, that generic base model forms a specific amp model. If you have a quote from him that contradicts that statement, post it. Otherwise, I have no reason whatsoever to think he means anything other than what he clearly stated.

    My point is with Modelling it doesn't need to stop at the reference amp, profiling can only ever mimic what its presented. Yes I know true modelling is to create an accurate copy. I didn't say accuracy wasn't important but you can make improvements e.g. more gain available than the real amp or less noisey etc.


    I also added " in my opinion"...

    You didn't say accuracy wasn't important. You said modeling isn't about accuracy. If we're talking about creating a model of a specific design, it is. If we're talking about modifying an existing design, then no.

    You're missing the point, as there is no EQ to match - the Sonic Maximizer process is phase-only, flat. In fact, on single-driver speakers you can't even make out the phase correction. The Lo & Process knobs are niceties but most people don't realize that they are there for convenience and are not, actually, the effect. I can point you to the patent if you wish.

    Well, no, it's not phase only. Let's look at the empirical data. Regardless how the Sonic Maximizer might affect phase, it does change the frequency response of a signal as evidenced by before and after analysis using a spectrum analyzer.



    The above image demonstrates how the Sonic Maximizer affects the frequency response at a setting of 3.0 for both, the Lo Contour and Process controls. The purple outline is the BBE post processed signal, and it clearly shows that both the high and low frequency content has been altered. If you're not willing to acknowledge that then you're simply denying reality.


    To my ears, EQ matching the post processed signal yields a result that's audibly indistinguishable. If you think you'd be able to hear a difference, try the following blind test. You'll find 6 audio clips below. The first sample is the original, unprocessed signal. However, can you guess which sample(s) have been processed with the BBE Sonic Maximizer vs. EQ matching? It should be pretty easy to distinguish between them if, as you claim, the Sonic Maximizer only affects phase.


    Original (Unprocessed) Sample


    Sample A

    Sample B

    Sample C

    Sample D

    Sample E

    Regardless of what Christoph was attempting to relay with his words, Alfahdg is completely correct (and obviously a fellow electrical engineer ;). Profiling is NOT modeling at all.

    I never said profiling is modeling. I said the Kemper uses amp models. The profiling process gathers data about an amp. That data is then used to automatically populate a complex base model of a generic amp with settings that form a specific amp model.

    The Axe-Fx Ultra was just a souped-up version of the Axe-Fx Standard. They both use the same amp modeling, thus there's no audible difference between the two. As far as the Axe-Fx II is concerned, all of the models (ie. II, Mark II, XL, XL+) are compatible with each other, and there's absolutely no difference in the sound quality between them because they all use the same modeling. A preset created with the original Axe-Fx II will sound identical on the Mark II, XL, XL+ and vice versa.