Posts by SgtPepper

    Hey Gert,
    I use Midi messages all the time.
    Here is the skinny..
    First Midi Messages are composed using the Hexidecimal number system.
    It starts at 00h decimal starts at 1.
    For the desired preset number to be transmitted it becomes.
    (Decimal Preset number-1)
    So if you want Preset 1 you program 0
    For preset 64 you program 63 and so on.
    What really gets sent is
    00 for preset 1
    3F for preset 64

    Also make sure your message is constructed correctly.

    A Byte is an 8 bit value containing two 4bit nibbles.

    A Midi Program Change message contains three Bytes.
    Header Byte , Value Byte and End of Exclusive Byte

    Header Byte = Cx where C is the upper nibble command for Program Change and x is the lower nibble desired midi channel.

    Value Byte = Desired preset number

    End of Exclusive (EOX) = F7 notates end of a particular message string.
    Quick Midi Channel Decimal to hex table.
    Here is Decimal 1 to 17.

    Note for Midi Channel selection keep them between 1-16 Dec as 17 Dec notates Omni which means any channel. You don't want that.

    5= 04
    17=10 (Omni mode) responds to any and all channel commands. You don't want this.

    Back to the program change for example say you set the Kemper on Midi Channel 4 and you want recall Preset 8
    The program change message

    Preset command header Byte Cx where C is the program change command and x= Dec Midi Channel number-1 becomes C3

    Preset change Value Byte = Desired Dec preset number-1 which becomes in this case

    Last the EOX Byte F7

    The complete message to send would be. C3 07 F7 .

    Any Midi Program Change needs to be constructed like the one above.
    Even MCC messages should be created in a 3 Byte format. Though MCC messages in theory can omit the EOX I would strongly suggest to included it.
    MPC messages must include an EOX Byte.

    The Kemper Midi Channel in this case would be set to 4.

    Search for a Dec to Hex conversion table on the web as it will come in handy for you in your programming endevours.

    Hope this helps.

    Ok say what you will...
    Instead of trying to defend what testing has been done, I maintain if you close the host program First you will have a much better chance of the host program not corrupting your hours of editing work.
    Yes in a perfect world you would hope that the code is bulletproof... As we are all painfully aware it appears that nothing is bullet proof with regards to the Kpa....
    I'm just putting something on the table that will help others avoid unfortunate outcomes if they are using Microsoft prior art windows versions, Did somebody say Windows 7 !
    Because something works in win 8 and 10 does not fit all.
    I'm trying to offer solid help....
    I am not wrong!
    Unless you try what I have suggested you can not make such a biased opinion one way or another.

    For all of the Kpa users whom desire to safeguard their work please close the RM before any abrupt disconnect of the Usb connection from the KPA.

    You'll thank yourself later.

    I am a very experienced programmer as well.
    Usb hot swaping has not been fully perfected. As Win 10 has made significant progress towards those ends. Prior versions are not hot swappable. Period end of story.

    Defend your code all you want....

    Its getting a little long in tooth dont ya think.
    Thourghly tested ! I don't think so...

    Having no significant progress in almost a year now is troubling at best.

    How's your Helix doing MonkeyMan!
    Version 2.00 ... Should have some good things. I haven't jumped in yet but it's getting close now.

    I have come to the conclusion KPA 3.02 is as good as this version of hardware is going to get.

    Kpa 4 and beyond is never going to be ready for primetime. The hardware design has too many technical IC die bugs and/or programing obstacles and limitations that even the best firmware and software designers would be capable of solving in a timely fashion.

    If the KPA engineering team finally get all of this worked out great!
    I really hope they do ...

    Or offer upgrade cards that can be purchased and installed that will provide a stable , flexible and future feature capable platform as it had been envisioned and promoted to be from the beginning.

    Either way until that happens....

    I can imagine adding the Helix to augment the Kempers excellent amplifier strengths.

    So MonkeyMan let us all know how you are using the Helix with the KPA.


    Hello , As a rule ..when using any open Usb communications it is a good idea to close the host ( PC ) program First. For some reason Windoze still thinks the conversation is still active waiting on the phone so to speak .....for answer that never comes!
    Then it has a tantrum because it can't " handle " HWND the silence ! A little programmers humour.
    Kidding aside .. If you follow this unwritten rule .. Blue screen of death will be no more.

    Are we all to bow on our knees just because one of many things were actually fixed.

    You guys are full of yourselves that's for sure!

    Let me ask you ... Who's your Customer?

    It is KEMPER that should be greatful that there are some willing to put up with this calamity of errors.

    A Company that has made millions who has the ability to hire the best programmers on the planet cant implement internal beta testing in a timely fashion ?

    Instead all these users put there capitol into a product that never becomes stable with regard to a Beta or Official Release to date.

    You belittle customers when they complain and then expect slobbering adilattion when you fix one obvious progrsmming oversite !

    I guess this is the age we live in today...
    Be happy with mediocure ....

    Steve Job's would have done this thing right!

    Know to be fair Line 6 has there own problems with Helix at this time.

    Funny how both companies had choose similar Ic's for the User Interface circuitry?


    I think we have a big problem NASA....

    How many KPA have been sold?
    By the number that had been touted that yielded A whole lot of R&D money....

    There is no reason why this products development is moving at a snail's pace having to rely on its customers to vet it.

    Either Mr. Kemper is living well. Or the money is being used for something else.

    KPA V 2.00 Hardware.

    How's everyone going to swallow that bitter pill.

    I mean all that R&D money isn't being spent on this platform. The remote didn't cost much...

    So I suspect the marketing strategy is to keep dribbling these releases and keep the beta testing publics hands full and keep the others intrest to wait it out until the next gen is ready for release ..

    Only then will we see what the wizard of KPA has instore for the faithful.

    My hope is that Mr. Kemper is as brilliant of a business man as he is to computer science and will make it possible for all of us to upgrade our existing hardware by purchasing a set of replacement cards which will be substsntially less than purchasing the next gen in its entirety. Thus fixing everything crashes , boot time along with upgrading the processing power and memory to deliver the product that he intended us all to own. Second to none.

    At that moment all of this investment of the customers time pay off.

    So if any of you reading this work for Kemper I'd think twice about the way you treat unhappy customers that only want the product they invested their money into ( That you get A paycheck from ) to work properly without headaches or rubing their stomachs while patting their head and clicking their heals three times.

    I've got my bullet proof vest on and a German helmet with the KPA logo on it ... Ready for incoming Sir!

    I find it curious that this particular screen shot has been seen so so so many times....
    Found in Beta and supposed releases....

    After how many years ?

    Someone can't get a handle on the Midi Servicing code?

    And these errors happen during particular UI states?

    That would point to a problem in the Main loop code as well.

    I'll tell you what the problem is ....
    I will have to assume you are using "Threads"

    If not then your using an interupt priority scheme.

    If it's Thread based they are stepping on one another.

    If it's interupt based your buffering and service methods have issues .

    But for the moment let's entertain the notion the programers logic is sound.

    Then the ominous Red flag is waving. Or in this case Blue Screen of death.

    If this was cut and dry... black and white all that have upgraded and use midi will face this issue.

    However I suspect this is not the case!

    There is something not quite right about all these uncommon phenomena occurences.

    Yes this is true Kemper has yet to release any KAOS that you could consider close to 100% stable >3.02.

    Yet you keep adding and switching up the code and appear to act as if there is nothing to fix first. That is perplexing.

    The more changes and additions you make to the code the less likely it is for you to ever find or fix what is really at the source of these amomolies.

    There will never be any stable release.
    So all of us just need to be aware that what could go wrong might go wrong when you least expect it too.

    Yet another reason to cut the initialization boot time to seconds not minutes.

    Corrupted Rigs? What corrupted them in the first place. Firmware ? Hardware? Software?
    Gotta be one of the three boys and girls.
    Ohhh it's the mediums fault.....?

    I'm not sitting in the IDE chair to lend a hand but when ever I have suspected an internal IC bug is present I would create my own bullet proof method of bypassing or insuring that pointers and or threads , program address stacks etc were forced to do what I expected in the event the Host IC didn't behave.

    Pass that on to the youngsters behind the IDE wheel wontcha.

    On the behalf of all Kemperians

    " We are all counting on you to come through "

    And don't call me Shirley.



    You are correct in assuming that indeed there should be no perceived difference between a mono chorus and stereo.
    What you have described that Mr. Kemper said
    Tells me that there are two modulators involved. Instead of one modulation wave table applied spanning the Left and Right ouputs.

    In the case of Mr. Kemper modulation approach when summed together you will have phase combing artifacts occuring.
    The comb effect happens in reverb but not quite as pronounced and with reverb is a natural occurence in the wild.
    agree with you that code compensation should be made for those who expect what has been the industry norm for guitar effects for ages
    Mr.Kempers first claim to fame before this wonderful stroke of genius was
    The ACCESS VIRUS as in Keyboard synthesis...

    So although the algorithm for profiling has been aimed at the Guitar Amplifier Market
    The operating system has been developed essentially from a Keyboard Players prospective. That's why the things you and every other guitar player expect such as allowing this mono phasing issue to even exist and call it normal or the inability to assign any parameter to the external expression port are behind the Guitar effects industry norm.

    We can only hope when 4.0 appears the operating system starts to approach par in many respects.

    It wasn't too long ago they expected us to use NRPN messages for external Midi Control in most of not all Guitar Players said WTF !

    Thank goodness they at least offered a spackling of MCC to work with.

    So the good is the KPA delivers great amplification!

    The rest is still way behind in the basic professional external controls and effects implementation that guitarist consider a given.

    Ofcoarse the in some of the KPA " Enlightened " types on this blog would never admit that this wonderful thing has some drawbacks that from its conception should have had implemented from day one instead of still doing catch up 5+ years later.

    And before you say it YesTrue Cab is a step forward.
    Great nice innovative... It would even be more awesome if everything else was caught up.

    And then we have "Morphing"(tm)

    I'll say this much .... and this goes out for all the players reading this.

    Think about this....

    If the KPA could recall presets without any dropouts instamtly most of us would never need morphing.

    Here's one more ...
    How fast do you think you can move a pedal with your foot from heal to tow in milliseconds.

    If your very nimble possibly 100ms ?

    That buys a lot of preset changing time does it not.

    But it's seamless?

    This is one of the greatest feats of marketing magic I have ever witness.
    The Marketing people at Kemper have brilliantly created a way to divert the users attention away from the preset recall latency issue while promoting this as some great new feature.

    How about fixing all the basic issues like instant preset recall then perhaps this morphing diversion ( although some may have a use for it) wouldn't have been needed in the first place.

    While your at it how about improving the power on time to play annoyance too.

    Ok I'm done ragging... I'll put on my bullet proof vest and helmet for the incoming onslot.

    I love the KPA and do not want to consider any other preamp ...

    I like every one else await the anticipated release of 4.0 which hopefully addresses 95% of what myself and other users with respect to Midi Control , External Control Port assignments and Effect upgrades/fixes along with industry standard routing options as well as User Interface improvements.

    I beg you.... Please
    I'd like to eat my last meal before you kill me.
    Peace to all Kemperanians!

    sambrox wrote:
    "Well, the modulation parameter is there to create movement across the stereo field, so it would actually be redundant in mono anyway."

    No you are misinformed modulation is produced by using an LFO table of coefficients to either shift pitch or delay line times in relationship to the desired LFO waveform used to create the offset lookup table .
    This may be used in such a manor as to yield a stereo panning effect.

    That point aside.

    When the Output = L+R there should not be any phase cancellation if proper input signal phase has been maintained.

    A chorus in stereo is a chorus in mono...

    If it's anything else something has affected the Input signals phase proceeding the application of the Chorus algorithm.

    Let me clarify ... Ofcoarse now if the code were written to use a sinewave positive going on the Right and negative going on the left to make a dramatic stereo image. There would be a problem when summed .... Still that would be flawed logic by the programmer.

    Instead for this example Sample_Blocksize=256 then use a
    2×(Sample_Blocksize) that constitutes
    (Input_Blocksize_R)(Input_Blocksize_L) applying the modulation waveform over the entire 512 word buffer which creates stereo modulation.

    If a user decides to switch the output to mono a programming Mono_Stereo_Flag should have been used to reflect the desired output mode chosen throught the entire effects routing chain so when applicable the code uses
    a different processing approach as in this case using (Single Blocksize Dry buffer) +( Single Blocksize Modulated buffer) instead of dual to produce a mono chorus with the identical characteristics of its stereo counter part.
    You can produce a single blocksize modulated buffer easily by taking every other sample across the double sized buffer this technique is called Downsampling.

    If the stereo buffer was 512 words take every other sample to produced a 256 word buffer.
    Accumulate [ (Dry Buffer ) + (256 downsampled modulated buffer)] = Mono 256 word buffer output which is copied to both Right and Left Blocksize output buffers respectively.

    Based on this example using a Sample_Blocksize =256

    Simply put you copy the same 256 word final effects mix output buffer to both left and right output streams. Maintains phase in Mono

    Well you guys are aweful touchy when it comes to this product of I which I own ... For the record I have no agenda whatsoever...
    What I have reported did 100% happen.
    After it happened I reset the globals and didn't bother to see if it would crash again.
    I do not need to open a ticket because I know how to avoid these types of issues. You see even firmware that is broken can work well enough to demo anything ... If it happens to do something unexepted you reboot and continue.
    I have no doubt all these features exit.
    I do have plenty of insight on exactly what your programmers are experiencing first hand.
    I've been through the nightmare of knowing there is something wrong within the haystack of firmware and hardware causes and possibilities with no one to turn too hoping to find a soltion .... Meanwhile having pressure from marketing people and others who want the latest inovasions released immediately!

    A programmers best friend are those reports from people that are repeatable.
    That makes fixing general "bugs" easy.

    But when there are reports from others with seemingly no rhyme or reason . Like the one I experienced.

    Ofcoarse the first thing to do is deny any problem exists because it hasn't happend to someone else or imply that it must be some sort of user error. Advice being do a reset ...
    If things are working why is there any need to pat your head and rub your stomach to get it to work?

    Or lastly since it hasn't happened to me you better submit a ticket.....

    All those reports of umpredicable and non reproducible issues are indictive of one phenomena....

    That my programming friends is a flag waving right in front of your faces.

    It means that there something not quite right somewhere within the digital eco system as in Hardware IC bugs , Compiling errors, assembly mapping errors, and lastly the code itself.

    These types of issues are the toughest challenges to overcome and rectify.

    Below are just some of the possibilities.

    Program coding issue. I have never written perfect code. Sometimes coding errors are staring you right in face and when you finally see them your kicking yourself.

    Bug in Compiler causing assembly translation and address pointer corruption.
    Assembler program memory allocation overlaps in final output.

    MCU internal die bugs that could cause interupt problems , memory corruption and buss contentions. Yes IC manufactures release bug riddled dies and attempt to provide workarounds after you have installed their Ics into hundreds or even thousands of a given product..

    You can write the best code ever conceived but when things like this are lurking it would be wise to find the root of the problem then access the fix or fallout scenario. As in recalling certain production run lots ECT...

    I know from extensive experience in this type of product development.

    I am attempting to be the digital Paul Revere of sorts. So instead of being offended maybe some consideration by the programming team should be given so that they can shorten or avoid the countless hours and nerve racking days and weeks it takes to discover these things on their own.

    All of you here in the forum have me pegged as a troll... Troll I am not.

    I am a life long rock guitarist that began playing at the age of 8 then professionaly from the age of 13 .......
    I've always had an interest in Electronics.
    Many years of gigging , partying and all the other perks ....
    One thing led to another and I found myself going back to school while gigging which eventually landed me a position engineering products just like this and more.

    Engineering is a love hate relationship.
    When projects are doing well it's great.
    Unfortunately in development of any digital audio device unforseen issues will most certainly appear when you least expect them.
    So you are unable to release the product.
    Meanwhile marketing is ready to release the product when the leds blink and it's making noise... That's the hate part.
    Its a rough gig .... I enjoyed the engineering aspect and overcoming problems along with the race to completion and release.
    But frankly speaking after experiencing the Kemper the quest was over for me and it was time for me to return to what brought all of these opportunities my way to begin with..
    I am an accomplished Musician that eventually ended up engineering devices for muscians.

    Muscian (Guitarist) first Engineer second.

    I am also a perfectionist at heart.
    I guess I could be more sympathetic to the plight of the KPA programming staff but someone has to crack the digital whip.

    My rig of choice is the Kemper Profiler.

    Nothing will ever beat the profilier at its core.

    Christoph Kempers programming genius has yielded an advancement in digital electric guitar amplification as profound to that of other great pioneer's of our time such as Leo Fender, Les Paul , Jim Marshall and Mike Battle just to name a few.

    In fact it is while I was doing comparisons between products side by side in an controlled environment it became apparent to me that Mr. Kemper imagined to create what all other Dsp engineers had been chasing for years

    " The holy grail of digital guitar amplifiers "

    Christoph Kemper will be known as Edison was to the light bulb or Einstien to relativity....

    That was the day I sent all the other samples back and kept the KPA for myself ...

    The race was over as far as I was concerned.
    No need for me to burn the midnight candle any longer.

    With regards to the Kpa it comes down to the user interface experience and other internal effect improvements to put the icing on the cake.

    I am 1000% for the KPA !

    That is my only angle ! Period end of story ...

    Nothing less... I could give a rat's ass about what Cliff does or anyone else....

    So Now you know the rest of the story ...
    It will be released in paperback soon.... :)

    I love all the Kemperians !

    Peace ....

    Of coarse these Guys never like what I have to say. Nevertheless here's my two cents on the wah subject. I tried the wah enough to conclude two things.
    1. There is really no substitute for having a nice analog wah.
    2. When I tried to use it I found it to have a lag somewhere if I had to estimate around 15ms
    Now maybe for others this is within their acceptable range. But for those who can actually feel what they play it is not.
    Secondly and most important Ofcoarse is that I experienced the ever ellusive erroneous KPA crash! Why? I can tell you that it appeared to me as one of three cases.
    1. Buffer overflow problem.
    2. Program Stack issue ( leaky memory)
    3. Shared memory buss contention or buss arbitration problems.

    I'm sure that it is problems like these that are plauging the KPA programmers this very moment and it is also why 4.0 has yet to see the light of the Kpa community. You see Kemper knows he can't afford to blow it.
    So if and when all this gets straightened out that will be the day all of these strange unpredictable un-repeatable things are put to bed.
    My advice would be only use the pedal for volume which is something that won't break the programic stacks back.

    Besides a great wah never goes out of style.

    Ahhhhhh.... Don't hold your breath..
    . or bet the family farm on it.... It could be we will all be too old or dead before vaporware 4.0 is ever released.
    So be happy with what you have to work with now because it may turn out to be as Porky the Pig says......
    " Uhh beeit uhh beeit uhhh bbbeit uh beeit That's all folks ! "

    Second time trying to post .
    Right Click on the .exe or the shortcut for the problem program.
    Select properties
    Select the Compatibility tab.
    Pick the OS you would like your program to on.
    In your case it was Windows 7 ?
    Click apply .
    Try running the program now!
    You should be a happy Kamper!

    Here is my suggestion to try...
    I personally use this combination and it sounds wonderful. I use in ears and for my output I use the Bose L1 Model II only! Do not use the Tone mixer POS as it will destroy your tone . Instead go directly into the Analog 1/4 inch on the Bose Base. Use the presets that sounded great with your headphones. You might want to tweak the KPA global output Eq and set a roll off at 8k 1.0 Oct -6dBu that should be in the ball park. Now In my situation performing a classic rock solo act I have backing tracks as well .. Intially after getting the Bose Model II system that included their little mixer I was very disappointed just like you are using the CLR. I'm thinking this has to sound better than this? Then I disconnected the BOSE mixer and plugged the KPA into the Analog input of the BOSE. It was like angels singing. So I came to the realization the Bose mixer was destroying everything. I set out to find a mixing solution. Allen and Heath mixers have always been known for great smooth and musical Eq sections and I saw this ZED 10:-Fx . I was skeptical because of its low price. But it was the best 240.00 I ever spent next to the investment in the KPA.
    This was the final clincher as the Eq is fabulous. On the Allen and Heath the KPA channel highs control is set at about 11 O'clock and the rest of the channel basically flat. But having said that even though I say basically flat the A&H is applying its sonic magic.
    The tone live is exactly what I hear with the in Ear monitors !
    If you want a hail Mary to try with your CLR I highly recommend you try the Allen and Heath ZED 10FX. Who cares about the effects in it.
    The price of admission just for its Eq was worth it. You have nothing to lose. You can always return it. It will make an unbelievable difference, You can not do any wrong with the Eq on the A&H . All EQ's are not the same !
    A Graphic Eq cannot give you the warmth and clarity that this little wonder of a mixer delivers at any price. The Bose L1 model II is a reference system as is your CLR. For that reason alone and for the sake in pursuit of the Kpa direct holy grail of tone live give this a try and let me know what you think. I've posted below the information for you. I get great results and know you will too.
    Allen & Heath ZED-10FX 10-Channel USB Mixer with Effects
    No tax

    My Kpa is setup as best that is possible. I have no problem with noise... Besides I think the Kemper Team has plenty of other things more important to ponder at this present time. Any suggestions that I post are based upon a solid background in such endevours as those of the KPA team... You can choose to apply what works and what doesn't for one's personal taste. Knowing something about the bits, bytes and words as it relates to any digital audio system will help anyone create better presets with any Digital signal processing devices KPA or external . It's all good!

    Some people say potato and others potato.
    I have read what Mr. Mitchell has expounded to you in 2014 and he's writes in affect that to paraphrase if you do not fill the bit width of an A-D or D-A S/N and dynamic range suffer.
    So he has some algorithm based on using FEEDBACK information obtained at the output Master. Quasi soft input expansion and output ducking, That might be and Oximoron by I digress...
    Fine and dandy .... I'm not convinced.., Besides are you implying that Kemper is employing a similar technique ???? I'm just stating what has been true since the digital audio revolution appeared . If you throw away bits , compand them or in anyway not utilize the full extent of the real bit resolution there is a price to pay.
    All 24bit converters are not the same They may say 24bits but deliver 20 usable bits.
    Anyway the moral of all the digital marketing hype that some like to use there are some things that can not be changed.

    Just remember the analog recording addage.
    Crap in = Crap out. You can't fix it in the mix but you can put lipstick on a pig.

    Maginfying low analog or digital bit streams amplifies noise ! Ofcoarse you can always try adding dither to mask the noise nevertheless it's noise.
    End of story ....
    That should be never be taken for granted.

    I think you better talk to somebody there at Kemper that knows a little something about digital conversion and learn about what the benefits are in maximizing the signal path before A-D and before D-A along with the impact it has on signal noise not to mention dynamic range before making a such an generic assumption. You may actually learn something useful.

    I think for most users coming from the analog amp world into the digital one these concepts of maximizing signal levels are not the easiest things to get a handle on. What I described above as a feature request would help 99.5 % Of all KPA users even if some have KPA degrees. Also to my knowledge no other product in the digital guitar amp arena has a feature for maximizing presets. You could name this feature PRESET or RIG FINALIZATION ©2016 KPA.

    My olive branch to you all.

    For input adjustment you set it and then lock it
    That will be applied glibally. If you have other guitars that vary then you can create input presets.

    For final outputs because of a presets effects chain this is not possible so currently you must twiddle things to maximize the output gain.
    Now a neat little feature request would be to have a soft button a user could press once they are ready to maximize a presets output level that would sample the player hitting hard chords for say 5 secs and automatically maximize the presets output level .
    Can I get a resounding KPA amen for that request?

    Remember you want to maximize your guitar input into the KPA without clipping. The same goes for the final output of the Kpa. Make sure you maximize all presets to just tickle the output clip led. Then for extra insurance back the output down just a smidgen to avoid the clip led. Although if I'm not mistaken if you occasionally see the output clip indicator you still have about 3dBu of headroom left before hard clipping. If both criteria input and output have been met you will have maximized your signal to noise ratio and have as quiet of an output as can be.
    Hope this helps.