Public Beta 3.1.0

  • Here we go, from the manual addendum:


    Pure Cabinet (or "how to cure a decades-old sound disease")
    "Pure Cabinet" will gently polish the sound of the virtual cabinet to move it toward the sound that you would hear directly - in other words: the sound of the cabinet without the microphone. The fundamental character of the sound will still be maintained.


    Patient History
    For several decades now, guitar amps and cabinets have been captured by microphones - this is the only way to capture the natural sound of the amp and cab, and convert it into an electrical signal for further processing, recording, or for further amplification by a PA during a live concert.
    With the advent of digital amps, every guitarist gained access to hundreds of different guitar amplifier and cabinet sounds, all mic'ed and faithfully digitized. Now, those sounds can be played easily through a PA, in a home studio, or via headphones.
    Digital guitar amps and virtual cabinets are a true paradigm change; in earlier times, amps were mostly heard directly, with no microphones involved at all. Even experienced guitarists often let a mixing engineer position the microphone, and only really care about the residual sound. With digital amps, this engineering is done before the event of playing live or recording. It is widely recommended among guitarists to use a full-range speaker when playing a digital amp - this allows them to take advantage of the virtual cabinet, ensuring that they hear the exact same sound that the audience will hear.


    Symptoms
    As a manufacturer of digital guitar amps, we found ourselves in an interesting situation:
    On the one hand, recording and live engineers had constantly praised us for faithfully capturing and recreating the sound and feel of the most precious tube amps and cabinets.
    On the other, we were hearing frequent complaints from new users that had a hard time adjusting to the full-range sound of digital amps. They would often describe the sound using terms like: "harsh", "nasty", "phasey", "boxy, or even "digital". They said the sound was far from being the nice, smooth and balanced sound of the pure cabinet they were used to. In short, they were missing their "amp in the room" sound.
    In internet forums, the experienced users would often comment: "You just need to get used to that sound. It is the sound that you have been listening to on every recording in your life. This is also the sound that your audience will hear, when you play live or on a recording.".
    And the experts were absolutely right. We, too, had been saying the same thing over and over.
    Some recommended using a guitar speaker with the digital amp, to get the "amp in the room" feel. We fully supported this setup, with our optional, built-in power amp, and the recently released feature of using Direct Amp Profiles. However, this did not cure the "disease" of the full-range sound.


    Diagnosis
    Eventually, we realized that this cannot go on forever. It feels very uncomfortable telling respectable users that their perception of the mic'ed amp sound is "wrong", no matter how widely used it might be.
    Can so many guitarists be mistaken? Or, are they absolutely correct in their first impression, and the more digitally experienced players have simply become desensitized over time?
    It's like telling them: "Get used to the pain! Look at me, I cannot even feel it anymore. I'm a professional".
    There are many theories floating around which attempt to explain the secret behind the "amp in the room sound":
    Firstly, any 4*12 cabinet has a better bass response, thus pushes more air, than a regular, full-range studio speaker. This can be matched simply by using a larger, full-range speaker.
    Then, there are some who believe that a closely mic'ed speaker does not capture enough of the surrounding room, and thus sounds too dry. However, if you placed your full-range speaker in a room, and played that sound, we think you would perceive that room, just as you would if you had your original "amp in that room". So, this does not lead to a solution either.
    So we further analyzed the problem. We mounted a full-range speaker into a cabinet, and a guitar speaker into a second, identical cabinet to compare the sound under equal conditions.
    The difference was immediately apparent: harsh, nasty sound components in the high-frequency range of the full-range speaker, playing the virtual cabinet/microphone, but no such nastiness from the guitar cabinet, when playing the amp sound with the virtual cabinet bypassed. This harshness was more or less apparent depending on which amp and virtual cabinet we selected. It disappeared on clean guitar sounds, since it is only distortion that stimulates those harsh frequencies.
    It is very difficult to equalize the nasty elements of the mic'ed cabinets without significantly changing the character of the sound. Attenuating the frequencies in question will make the sound too dull, and it still won't sound like a pure cabinet.
    Certainly, there are ways to control this harshness to a certain degree: Good positioning of the microphones, and mixing two or three microphones to average this effect, can lead to pleasant results. You can also use narrow-band equalizing to filter the nasty frequencies and fit the sound in the mix. However, this is more like treating the symptoms than curing the disease itself. Finding the right balance between the desired character and color, while avoiding nasty elements in the sound, is both difficult and time-consuming.
    Once the guitar is fully embedded in the mix, the disturbing frequencies will likely be masked by other instruments, hence you would not usually notice them in a final mix of a professional recording.


    Medicine: Pure Cabinet
    For the Kemper Profiler, we have developed a completely new method of recalculating the sound of a virtual cabinet. We call it Pure Cabinet. The technique is Patent Applied For.
    When activated, the harsh frequencies are identified and modified in such a way, that the “phasey” sound turns into a smooth, balanced sound similar to a pure amp in the room. At the same time, the main character and frequency response is maintained, so no further tweaks are necessary.
    As a proof of concept we have let a number of these "desensitized" professional players and producers test the new Pure Cabinet feature in several situations. Their first reaction was along the lines of: "That pain that I got used to over the years, is now gone. It's a huge relief." They did not want to deactivate Pure Cabinet in any situation - there was simply no reason to switch it off again. So, much to our surprise, they did not miss the original mic'ed sound for a second. Not one of them looked back.
    All applications that use the mic'ed sound (virtual cabinet) of the Profiler can benefit from Pure Cabinet: recordings, live venues, full-range monitors, in-ear monitors, or just noodling with headphones on.
    The full-range sound, treated by Pure Cabinet, can be further processed with smooth equalizers. Without those nasty frequencies in the way, it will fit easily into the mix.


    Medicine Prescription
    Pure Cabinet is a global setting that affects all Rigs. It naturally adapts to the individual sound of each Rig - the more unbalanced the original Rig, the more impact it will have. With fully clean amp sounds, Pure Cabinet isn’t noticeable.
    Pure Cabinet uses a switch to engage it and a continuous control to set the intensity of the effect. That's all! By switching on and off you can directly compare the impact of the effect versus the unprocessed cabinet sound.
    The Intensity parameter allows you to control the degree of processing. If you are more into crunchy, blues sounds, you might prefer higher values of Pure Cabinet, creating a more open sound and bringing the character even more towards an amp in the room. If you are into hard rock or metal, you might prefer lower values, to emphasize the "microphone character", while still dampening the "phaseyness" of the sound.
    Pure Cabinet is processed on the fly, thus the data of the Rigs are not affected by Pure Cabinet. The original sound of each Rig remains unchanged, and Pure Cabinet can be deactivated and reactivated at any point in time.


    Aftermath
    So, if the professionals aren't looking back since discovering Pure Cabinet, what exactly is it that they leaving behind?
    It is the sound of mic'ed guitar amps, heard on billions of recordings and concerts over several decades. The artifacts described above just had to be accepted - there is no way to cure them with traditional techniques. Only digital guitar amplifiers can handle such complex processing as Pure Cabinet requires. It simply sounds better and, surprisingly, more analog and real.
    Now, do Profiles of tube amps sound better on the Profiler with Pure Cabinet? Simply, yes! Can the sound of tube amps be improved by profiling these? Yes! When profiled, it sounds absolutely authentic. With Pure Cabinet engaged, it sounds even better.

  • OK ..... picture a humble pie and me eating it. Clearly my impatience got the better of me.


    Anyway .........


    I've just spent 30 mins of so with my MB profiles and my ATH-M70X headphones so I could test Pure Cab.

    This has taken the KPA to the next level
    ..... it achieves something I thought would be near-on-impossible to do :)

    All I did was engage Pure Cab in the Output Menu and set it to " 5 " .... when in doubt I work on the " half is better than nothing or too much " approach


    The only way I can describe it is this way:-


    -> with any profile I have ever used, even the MB ones - which have in my opinion brilliant mic placement, there is *always* what I would describe as noticeable mic "fizz" / "hash" / "notchy-ness" / "harshness" ...... its subtle buts its always there - we all know what it is and even multiple-mic'ing only helps a bit ...... its impossible to EQ out or get rid off ..... or so I thought.


    -> I pulled up a range of my favourite MB profiles and toggled Pure Cab on/off at the 5 test setting


    -> it quite literally sounds like the mic is removed from the sound and you have the often-mentioned amp in the room sound .... its subtlety is its strength ..... its quite staggering .... I never expected this sort of thing to be "doable"

    I actually think this is a much bigger game-changer than even 3.0 "direct" profiling.


    I had no idea this would even be possible, let alone that it was " in the works ".


    Wow ..... just wow !!!


    Massive Kudos to Kemper.


    Ben

  • For those who might have trouble finding the magic Pure Cabinet button: It's in the Output section. (Press and hold the outbut button).


    Thanks, yes page 5/6


    The rig manager beta seems a bit buggy; when I load a performance by clicking on it there's sometimes a delay, even if the delay stomp is switched off; so I have to switch it on and off again to make it go


    edit: I think it doesn't load the right performance: say I click on my "Morgan AC 20 performance", on the kemper screen it says Morgan ac 20, but I hear the sound of an other performance.
    Anyone else?
    Maybe I'm not posting in the right forum, and we should open rig manager beta 1.5 thread?

  • This is seriously fucking sick :D
    I won't be able to test it until like 2 weeks from now, but if history teaches me anything Cristoph would not put such a feature out if it weren't mature - where the term mature means that noone with properly functioning ears could hear it and not drop their jaw to the floor.
    All hail Cristoph!

  • Damn, I have a gig tonight and would very much like to do it with the new firmware, is it reasonably stable?


    Also, I've dialed down the highs on many of my rigs in order to control the fizziness, do I need to raise them back after switching pure cab on? Mind you, I won't be able to give it a try until I get home at the end of the day, that's why I ask, so I can plan ahead.

  • Sorry but I can't get the meaning and of the pure cabinet. We have the "perfect" sound of our digital amp (KPA) because it is the same sound has our favourite amp with the chain of our mic/amp and cabinet. Right?
    If I have the "perfect" sound for example for my recording what is this that can make the "perfect" better?

  • Just what the doctor orders!!!


    Can't wait to get my hands on the pure cab thingy. Thank you Kemper team this really is a nice one. Makes me wonder what more have you got in the box without letting us know! :)
    Ingolf, I read your analysis with a lot of joy. I wished my doctors would explain some of the things that bother me time and again so well and conceivable. Thank you for letting us know. :)


    Now, without further ado get the guitars out and let's roll.


    Joachim