Input light going red regularly

  • Hi all,


    I noticed at my gig on Friday night that the input light on my toaster keeps lighting up red... there was no obvious clipping, but I was just curious what the options are to ensure the front-end doesn't get overloaded?

  • To be perfectly honest I find it one of the most confusing things about the Kemper and no matterhow many times I read the manual or watch the videos it doesn't become any clearer ^^


    I do two things (probably both wrong). First I just play and watch the input light . I turn the clean sense down until it stops going red. I make a mental note of this then cross check it with the balance between clean and dirty, I take a profile and increase the gain from ) - 10 if the profiles seem about the same level then I go with it. If they sound fairly similar I'm good. However, I tend to find that the clean sounds are way to loud compared to the dirty sounds with the clean sense close to 0 or in the positive numbers.


    I actually used to have it locked at -7.1 but have started to edge it up a bit lately. I don't think most others use settings as low as me though so either I play like a beast or my input light might be wrongly calibrated ?(

  • The very first thing that hit me when I switched profiles in the shop's demo booth was ----- "Bloody hell those cleans are loud!!!!!" :D


    I got the KPA home and started turning down all the clean rig volumes then read the bit in the manual about clean sense and realised I'd wasted about an hour twekaing. An the moral of the story is - RTFM Alan you muppet !

  • Basically Clean Sens is for levelling clean and distorted sounds in a way that they are equally loud. Keep in mind that a clean sound can be perceived louder than a distorted sound without being actually louder. Due to natural compression coming with distortion such sounds usually have less prominent peaks than a clean sound.

    Now when it comes to adjusting Clean Sens I think the way to go is the following: Take a mid gain sound (preferable a factory sound with gain around 5) and compare the perceived volume with gain at 5 and gain at zero. Adjust Clean Sens in a way that both sounds are perceived equally loud without the input light going red (which depends on the output of your PU).


    Cleans Sens is not for levelling all your clean and distorted sounds to each other (there are too many parameters in the signal chain for that)! That's what rig volume is for. Also Dist Sens is not for levelling the volume of distorted sounds. It is for compensating the global distortion due to the different outputs of different pickups.

    I could have farted and it would have sounded good! (Brian Johnson)

  • Cleans Sens is not for levelling all your clean and distorted sounds to each other (there are too many parameters in the signal chain for that)! That's what rig volume is for. Also Dist Sens is not for levelling the volume of distorted sounds. It is for compensating the global distortion due to the different outputs of different pickups.

    i know and totally agree with everything you said. My point was that All the clean sounds had massively increased perceived volume relative to distorted sounds. So instead of reducing the level of every clean clean sound, I could have saved myself a massive amount of work by just turning the clean sens knob. ^^


    The confusing thing is that the manual doesn’t say anything about using it as an input gain control to stop the LED going red but I thought nk the videos do.


    “ Clean Sens

    Different types of guitars produce different output levels depending on their pickups and string gauge: for example, humbucker pickups generate higher voltages compared to single coils, and active guitars generate even hotter signal levels. If you feel that clean sounds are either very loud or very soft compared to distorted sounds, you can adjust Clean Sens to a level where clean sounds have the same perceived loudness as distorted sounds. Clean Sens determines the volume of clean sounds, but not the way that the amp or the effects are driven. A guitar with low output level stays cleaner; a hot guitar will still distort more easily.

    Extremely “hot” guitars can generate unwanted distortion, indicated by the INPUT LED flashing red. This is only relevant for clean sounds, however - prominent amp distortion will completely mask a subtle clipping of the input.”


    The confusing thing is tryng to get the input not to clip and turn the LED red while still retainingthe correct perceived loudness.

  • i know and totally agree with everything you said. My point was that All the clean sounds had massively increased perceived volume relative to distorted sounds. So instead of reducing the level of every clean clean sound, I could have saved myself a massive amount of work by just turning the clean sens knob

    Yeah, I already understood that in your previous post. I just wanted to give some general advice for all users who are interested.


    The confusing thing is tryng to get the input not to clip and turn the LED red while still retainingthe correct perceived loudness.

    I'm wondering about this. My MusicMan Luke II has active EMG's and I have to crank Clean Sens a lot for turning the LED into red. That's why I think that PU's have to be really hot for a red LED.

    I could have farted and it would have sounded good! (Brian Johnson)

  • I don't use any high output PUPs at all. I play mainly 3 PRS. The DGT has vintage output PAF style, a P22 with prototypes of the 85/15 and a 513 that I tend to run in single coil or low output humbucker. My other main guitar is a self build with a pair of Seymour Duncan P-Rails which I use in the P90 or parallel humbucker settings most of the time. Set to 0 I get red fairly easily and I need to go down to around -5 to make sure I never hit red even on my hardest playing. I know I do pick hard and I play with 11 - 49 most of the time so I probably put out more signal than many for the same PUPs but I do wonder if the calibration of the LED is a bit imprecise to put it mildly ^^

  • Yeah, I wonder about that too. I think my active EMG's are hotter than your PU's und my Clean Sens is at zero with no clipping problem at all. On the other hand I'm playing lighter string gauge (9-46). With my Ibanez Jem also no problem. What about distance between PU's and strings?

    I could have farted and it would have sounded good! (Brian Johnson)

  • I just upgraded the pups in both my Les Pauls - I'm running a set of Bare Knuckle Rebel Yells in one (fairly hot), and some Bare Knuckle Mules (PAF style) in the other. Reduced the clean sens to 0, and not getting a red light now, no matter how hard I thrash away (giggidy).

    Use 10-52 strings on both guitars, about 3mm from the bridge on both.

  • 10-052's were my string of choice for about 20 years :)


    Good question about the pickup height. I can't remember measurements but I don't like them too high (probably a little lower than PRS recommended factory setup). Because I pick hard with a Jazz III and I like to bend too much I tend to have my action higher than most to avoid any fret noise and to be able to really grab the string.


    I wonder if my light is just overly sensitive. At the end of the day, I am happy with the sound so am not overly bothered either way but better input monitoring would be a nice feature. I wonder if it could be added to the main screen like the tuner function as the hardware wouldn't support any other metering? Then again if the KPA is as forgiving of gain staging as seems to be the case, input metering might not be that important anyway.