Kemper Profiling Amplifier - sound clips - continuously updated

[ericmelvin10]

I'm not saying the AXE sounds bad, or are restricted, The Axe has a lots of good tones and a lots of parameters to tweak your sound, In fact, you must tweak your power amp parameters to start sounding really good, because the axe (ultra) from factory does not sound ok to my ears.

It's not compare apples to pears, we are comparing sounds and we should despite the way they are created. Unfortunately, good or bad sounds are a subjective question...

[hoss33]

Originally Posted by ericmelvin10

I've done a frequency analysis for the kpa and the Axe ultra of the dumble preset that Xavi's has... And the AXE has no freqs above 11000 hz while the KPA has freqs still visible in 14000 hz ...

[Scott Peterson]

I'd like to see the graph from any amp/cab that a guitarist uses that has frequency information at 14kHz. Let alone one that shows that amplitude at that frequency corresponds in any way with 'compression'. It's not making sense to me.

Eric, maybe I am stupid, but I don't get your last few points about dynamic range.

It's fine to share your subjective opinion that one box is better than another box and why, but I am not comprehending your reasons why with the math and logic presented.

[AdamCook]

Originally Posted by ericmelvin10

It's not a matter of taste when I speak about compression, I've done a frequency analysis for the kpa and the Axe ultra of the dumble preset that Xavi's has... And the AXE has no freqs above 11000 hz while the KPA has freqs still visible in 14000 hz ... So the KPA has more freq components than the Axe, and less compression on overall sound (you can see it while analyzing the amplitude of each freq at the same point with the same volume; then you realize that the axe has less variation on amplitude per freq than the KPA ... so the axe is more compressed and the kpa is more dynamic.). You also can do an average comparison.

It is fine if you prefer the tone of the KPA. I am not debating whether or not it sounds good because I haven't even heard one. But some of your scientific conclusions are incorrect.

First of all, the comparison should be made between each modeling product and the original amplifier. Not comparing Axe-FX vs KPA. Just because the KPA model has more frequency content above 11khz doesn't mean much of anything. If the original amp does not have much content in that range then it is the Axe-FX that is more accurate. You don't know that because you're not comparing it to the original amp.

Of course, doing this exercise is relatively pointless anyway when comparing the sounds because the content in that frequency range would have pretty much zero influence on we perceive as the "tone" of the amp.

Furthermore, your statement on compression is incorrect. Looking at the amplitude of different frequency bands when inputting a signal at constant amplitude tells you nothing about compression.

[OIO]

Originally Posted by ericmelvin10

Don't forget that with the AXE, you are subject to the programmers presets / amps / cabs / ... They give you the main tools to build your sound.
You are restricted to the way they model the physics and interactions of a real amp.
And, as you know; in theory, theory and practice are the same; but in fact, they don't. Some interactions and behaviors are not predictable, so this is why we always found some "strange" or digital sounding, compression... As you already know, modeling something is simplifying the real world; so in every element modeled, an inherent error/simplifications has done. If you model each component = at least 1 error/simplifications per component.

With the KPA, you only have to "profile" your already done sound, and also gives you the possibility to exchange your amp / cabinet with other presets and of course other people. It takes the sound and adjust it to sound and feel like the profiled amp; and this is what we are waiting for, THE SOUND; I don't care if my Transformer delivers more compression when i put +2v!!! I want the same fxxxxg sound. It's true that you are subject to the programmers who decided what parameters are modifiable by the profiling process, but they are based on the sound not in the physic behavior of a concrete amp. What if you have changed some caps and resistors in your amp to sound better... It's impossible to recreate that with the AXE, only if a gentle programmer does it for you.
With the kpa you only have to wait 50 seconds.

Eric, despite the fact its not released yet, i still think your opinion is valid

Every modeller is restricted to something, of course the AXE is restricted to the way it models the physics of components. But what really matters is the quality of distortion.

The way you say "you only have to wait 50 sec", it seems the profiling is always perfect, and thats not what i hear, im really impressed with some of the sounds but some of them yells me the restrictions of the device. Is it the profiling process? the profiler? I dont know.

Im no beta tester of any of them, im actually deciding on wich to spend LOTS OF MONEY. so far my feeling is you may take more time to build a patch in the axe , but KPA may not profile some types of amps properly.

I really want to test both before buying i may not have this luxury, and the axe looks a better bet. Yes, some models sounds a tad compressed, but quality of distortion still is a lot more (in)valuable for me.

[MaxTwang]

I still stand by my original comment that comparing the KPA to the Standard and Ultra are not valid. You're comparing KPA's un-released product to FAS's discontinued products.

I had an Ultra and have an AxeII. What your calling 'compression' I believe was a lack of detail and was most evident on cleaner sounds. I can confirm this is not an issue with the II. I expect Firmware 3 adds even more delicate details to the sound.

Regarding side by side with an amp, the Dave Cleaveland sessions identified the KPA was having troubles reproducing lows which didn't perfectly model the amp. One of the KPA-Beta's posted a clip a week or 2 ago and at about 2:20 or 2:26 a high gain amp was A/B's and the low-mid hole was still clearly there. Both of these were evident on the clips. So you could be saying the old Axe units sound better because they don't have the 'low end donut' like the KPA!

To me, I really don't care who more closely reproduces the sound of a specific amp. I want to find out who inspires me like a couple of great amps I've owned.

In the 6 weeks I've had the AxeII I've had too many nights where I got out of bed to play the AxeII for hours. A piece of gear hasn't inspired me like that since 1982 when I bought the Boogie Mark II.

If the KPA does the same, I'll be crazy from sleep deprivation. Crazy and happy.

[donbarzini]

Originally Posted by OIO

Eric, despite the fact its not released yet, i still think your opinion is valid

Every modeller is restricted to something, of course the AXE is restricted to the way it models the physics of components. But what really matters is the quality of distortion.

The way you say "you only have to wait 50 sec", it seems the profiling is always perfect, and thats not what i hear, im really impressed with some of the sounds but some of them yells me the restrictions of the device. Is it the profiling process? the profiler? I dont know.

Im no beta tester of any of them, im actually deciding on wich to spend LOTS OF MONEY. so far my feeling is you may take more time to build a patch in the axe , but KPA may not profile some types of amps properly.

I really want to test both before buying i may not have this luxury, and the axe looks a better bet. Yes, some models sounds a tad compressed, but quality of distortion still is a lot more (in)valuable for me.

men can choose whatever they want, the Kemper clips sound much more open, less compressed and more realer then the Axe IMO and they are not even on Version 2. I had the Axe Ultra and the Axe II, II is more compressed than the Ultra and both are less realer sounding IMO. Once I get the Kemper, I may feel the same about that unit as well but so what? One fully grown male's opinion will not always be the best for other men. I think these beta men have given a lot of valuable information and it ultimately led me to pre-order one, I had no desire to buy that ugly looking thing at first but now it is looking beautiful:-)

[ericmelvin10]

Compression is when you rise the low "volume" notes and you lower the high "volume" notes (simplified explanation).

If I play the same with X-gear and Y-gear and you can see with the X-gear that the "volume" is almost the same in all the wave, you have compression. If you see that in Y-Gear you have peaks of "volume" here and there... it has more dynamic range thant the X-gear. You can see it in the soundwave and in a freq analysis.

http://en.wikipedia.org/wiki/Dynamic_range_compression

[Scott Peterson]

Originally Posted by ericmelvin10

Compression is when you rise the low "volume" notes and you lower the high "volume" notes (simplified explanation).

If I play the same with X-gear and Y-gear and you can see with the X-gear that the "volume" is almost the same in all the wave, you have compression. If you see than in Y-Gear you have peaks of "volume" here and there... it has more dynamic range thant the X-gear.

http://en.wikipedia.org/wiki/Dynamic_range_compression

I am very aware of what compression is. I am very aware of what dynamic range is. I understand the concept, my question wasn't challenging you in any way.

Your logic doesn't make sense to me though. What amp and speaker has content at 14kHz? Typical speaker frequency range for guitar cabs is pretty limited; the guitar speaker is a lo-fi device by design... there isn't much above 6K at all on any given 12" speaker I am aware of.

What speaker cab did you 'profile' with the KPA that has context at 14kHz? How do you compare the 'compression' of one preset - that someone might have dialed that way on the Ultra versus the 'non-compression' of the KPA... based on what? A profile of a preset? Might that not be, counter to your assertion, some error in the accuracy of your profiling if it is derived from the Axe-FX? Did you profile an actual Dumble amp/cab instead?

I'm honestly confused. The last set of opinions you offered honestly don't make sense to me and I am trying to understand them as you posted them. No offense intended, just wanting more explanation. I'm not trying to be 'right' here; I'm trying to understand what you posted.

[ericmelvin10]

The "clarity" other people says could be some factors:

The "resolution" of the gear, than can produce subsamplig effects.
The way they synthesize/modify the output sound (eq, exciting harmonic components, synthesize using frequency components of the actual sound + white noise... )

I'm not a super-expert in terms of sound, and I'm the worst teacher in the world, but I passed 6-7 years of my life programming applications for analyze, study and transform audio/video, so I've a little idea.

[OIO]

Originally Posted by donbarzini

men can choose whatever they want, the Kemper clips sound much more open, less compressed and more realer then the Axe IMO and they are not even on Version 2. I had the Axe Ultra and the Axe II, II is more compressed than the Ultra and both are less realer sounding IMO...One fully grown male's opinion will not always be the best for other men

thanks for supporting my opinion, i mean, thats your point right?

KPA may be realer, but what it lacks to be real may be what i consider essential and AXE may be less realer but may have this im looking for.

does any of them have problems reproducing the low-mid frequency, problems in its dynamic range and how it travels in the avaiable dynamic, frequencies above 11hz? those points would only aply for me if i was not sure how they sounded and most important how i evaluate sounds for my taste.

[ericmelvin10]

Originally Posted by Scott Peterson

I am very aware of what compression is. I am very aware of what dynamic range is. I understand the concept, my question wasn't challenging you in any way.

Your logic doesn't make sense to me though. What amp and speaker has content at 14kHz? Typical speaker frequency range for guitar cabs is pretty limited; the guitar speaker is a lo-fi device by design... there isn't much above 6K at all on any given 12" speaker I am aware of.

What speaker cab did you 'profile' with the KPA that has context at 14kHz? How do you compare the 'compression' of one preset - that someone might have dialed that way on the Ultra versus the 'non-compression' of the KPA... based on what? A profile of a preset? Might that not be, counter to your assertion, some error in the accuracy of your profiling if it is derived from the Axe-FX? Did you profile an actual Dumble amp/cab instead?

I'm honestly confused. The last set of opinions you offered honestly don't make sense to me and I am trying to understand them as you posted them. No offense intended, just wanting more explanation. I'm not trying to be 'right' here; I'm trying to understand what you posted.

Sure, it was a fender 2x12 celestion v30, with a sure SM57 mic.
I used a freq analyzer and It returned that the max freq in the AXE clip were 11000hz, and the KPA 14000hz ... as you know human can hear up to 20000 hz, so for me It makes sense in terms of how much frequencies can reproduce the KPA vs the AXE.
The compression was explained after that, I mixed 2 explanations together, of 2 different things.

I hope it's clear now.



Guitar Freq Range:

Accoustic Guitar
1-15 KHz

Electric Guitar
1-15 KHz

* It's true that a speaker usually has a range of 6KZ, usually the V30 are up to 5Khz.

[donbarzini]

Originally Posted by OIO

thanks for supporting my opinion, i mean, thats your point right?

KPA may be realer, but what it lacks to be real may be what i consider essential and AXE may be less realer but may have this im looking for.

does any of them have problems reproducing the low-mid frequency, problems in its dynamic range and how it travels in the avaiable dynamic, frequencies above 11hz? those points would only aply for me if i was not sure how they sounded and most important how i evaluate sounds for my taste.

You need to spend your hard earned money on what you feel will work best for you. I will be spending my hard earned money, mostly stacks of singles and fives from my weekend dancing gigs, on the Kemper.

[ericmelvin10]

I don't want to start a "fanboy" war... Only comment objective things and my impressions.

Buy what you want!

[Scott Peterson]

Originally Posted by ericmelvin10

Sure, it was a fender 2x12 celestion v30, with a sure SM57 mic.
I used a freq analyzer and It returned that the max freq in the AXE clip were 11000hz, and the KPA 14000hz ... as you know human can hear up to 20000 hz, so for me It makes sense in terms of how much frequencies can reproduce the KPA vs the AXE.
The compression was explained after that, I mixed 2 explanations together, of 2 different things.

I hope it's clear now.



Guitar Freq Range:

Accoustic Guitar

1-15 KHz


Electric Guitar
82-1319 1-15 KHz

Fender Celestion V30? That's new to me.

The Celestion Vintage 30 frequency range response is: 70Hz to 5kHz. (Source: http://professional.celestion.com/gu.../spec.asp?ID=4 )


A Shure SM-57 has a frequency response of 40 Hz to 15kHz. (Source: Shure)


...and you captured audible content from a V30 speaker with a SM57 at 14kHz or just measured it? What was the amplitude? From the real amp cab? From the profiled amp cab in the KPA? I don't understand where you are getting that measurement, nor how it came to be.

PS - I'm not engaging in a fan boy war, nor questioning anyone's choice of how to spend their money. I don't care if you buy this box, that box or no box at all. Really, I don't. I'm not comprehending, based on my knowledge and experience recording, how you get content at 14kHz a) in the first place; b) how that has anything to do with 'dynamic range' or 'dynamic response' or how that applies, as Eric said it did, to 'compression'. In my opinion and experience, none of that makes any sense to me based on what he's posting.