Overdrive clipping: very annoying noise with my new Strat

  • Howdy,


    I just bought a used Rocketfire Strat with handwound pickup, the model is 1954 s series. Great bell tone and twang and everything. Tried with Kemper: nice clean and distorted sounds.


    The problem occurs with overdrive sounds: as you can ear in the attached clip, the Kemper makes a horrible clipping noise if I pick just a bit harder. I'd like to know if the problem is related with the vintage pickups, which don't produce a high output but are very sharp and the attack is pronounced. So I attached the unprocessed guitar sound, played with similar dynamic. Can someone be kind enough to reamp the signal through the same rig (Ceriatone SSS SRV by Einar Nysted on rig exchange)? Thank you very very much.



    troubleshooting:
    I tried to lower the clean sens, (though both leds stay green) up to -12 db, no change at all;
    I didn't touch anything on the original profile; some other overdriven profiles have the same behaviour, including commercial profiles;
    Soundcard input is fine and I can hear the noise with the headphone output of the Kemper too;
    With other guitars I own the problem doesn't occour.
    Already tried a system reset;
    Guitar action and pickup height are fine and if I pick open strings the issue is still here. Strings are brand new; I also tried to dampen the tremolo strings. Unplugged, the guitar doesn't make any strange rattle sound. Truss rod is fine too.

    If I fiddle with the low cut on the graphic equalizer, the noise reminds a ring modulator effect.
    With my cheap zoom g2 unit, the guitar seems fine.


    Please help me! Thanks again!

  • I'd like to know if the problem is related with the vintage pickups, which don't produce a high output but are very sharp and the attack is pronounced.


    After a quick listen with headphones I hear just that - a sharp attack as is typical with lower output single coils.
    Try lowering the Definition parameter (~below 5) in the AMPLIFIER module, to give the profile a 'fatter' character.

  • I have had the same instance. For my clean sound I had to move the EQ to the stomp section. Also because I play a 7 string, I get an 80hz boom when switching patches and a hard attack. To compensate I have an EQ in the effects section that helps to stabilize the 80hz, but I still wonder if it is something in the KPA. Just using a work around for now. But will investigate more when time allows.

    “When the power of love overcomes the love of power the world will know peace.”

  • Why do you wonder if it is "something in the KPA" that you have to work around?


    Whenever a profile is created, the settings on the amplifier used to make the profile are the settings for a particular sound, with a particular guitar.


    If you use a different kind of guitar with the profile, you may need to adjust some of the parameters to get the sound you want from the profile. You would likely have to adjust the original amp to get the sound you want, too.

  • I strike a blow for SancturSolaris: a profile that sounds dull/harsh or too much bassy/trebly with a different guitar is a matter of settings. Another thing is a profile that produces "booms" or other strange sounds. I don't think that the original tube amplifier can produce that sort of thing (at least, I never heared it in any amp)

    I don't hear and low frequency content in the reamped example that wasn't present in the DI track. I checked with a frequency analyser and it confirms that. If anything, the DI track has a lot more very low frequency energy in the attacks.

  • As always it is hard to reproduce most issues on a different setup. What I know is that that the Kemper has always worked perfectly until recently when a sudden explosive like boom would occur. This is on clean channel sounds when the F# on string 2 is played with a hard attack, I solved it by moving an EQ to the stomp section rather than the effect section and considerably lowering of clean sense.


    During patch changes from a high gain rhythm preset to a lead patch the same boom would occur only when the first note was stuck. Never at any other time. Corrected this by keeping the EQ in the effect section but lowering the 80hz.


    Recently, the change from a lead patch to a high gain rhythm patch started having the odd boom. It only occurred on he first struck note and not at anytime afterwards. I solved the issue, but not totally, by keeping the EQ in the stomp section and lowering the 80hz.


    This is annoying at the very least, but something I am sure I can overcome. I do not post often on the forum as I become frustrated by many of the pedantic responses. I only update threads when I have discovered something note worthy.


    The problem does exist and whether it is with the KPA or something else will eventually be discovered. Either by myself in a very timely manner, or probably around the same time we have an editor when Kemper discovers a solution.

    “When the power of love overcomes the love of power the world will know peace.”

  • Have you tried recording a clean DI of the pure guitar signal and analysing it in a frequency analyser in your DAW? Just to rule out that there is anything wrong at source. I once had a guitar that would boom and it turned out to be a shielding issue.

  • @alex_it


    This is just my personal opinion but I have a feeling the guitar is the culprit. I am a long time Strat player and what I am hearing in your clips sounds very familiar to me. I used to experience the same type of sound when using my Strat with overdrive or distortion tones.


    Here is a tip I learned from a very well respected local luther and guitar builder. Lower your pickups. I can't give you an exact measurement as all pickups are different, and it will vary depending on your style. But definitely try bringing them down a touch. Also I would suggest angling them so they are lower on the bass side as those strings create a wider arc when vibrating. Another tip is to have the neck pickup lower than the middle, and the middle lower than the bridge pickup. Again, this is to accommodate the fact that the arc is wider further down the string length.


    Some amps attenuate the problem more than others which is why you may not experience this issue with every profile.


    Give it a try and see if it makes a difference.

    Husband, Father, Pajama Enthusiast



  • Thank you mightypudge and the other people for your replies.
    I already tried to lower as much as possibile the neck pickup (pickguard level), the signal was weaker but I still could hear the noise.
    I already know the other tips you recommended to me, indeed this and my other guitars are set like that.


    I once had a guitar that would boom and it turned out to be a shielding issue.


    Can you explain what the shielding has to do with this kind of noise? We're not talking about a buzz noise.. maybe you mean a wiring issue?
    thanks


    I don't hear and low frequency content in the reamped example that wasn't present in the DI track. I checked with a frequency analyser and it confirms that. If anything, the DI track has a lot more very low frequency energy in the attacks.


    DonPetersen, surprisingly I slightly reduced the noise by adding an eq with -7 db on 4347 frequency. The bass reduction seems to be ineffective, indeed if I set a low cut the noise is much more unbearable, like a ring modulator effect as I stated before.

  • Ah I think I missed your "ring modulator" description. This to me sounds then like "stratitis", I'm afraid. I'm not really sure if there's a certain cure, only remedies. From what I read, it can be an accumulation of many things, but the biggest culprits are too low action and too much pickup magnet pull.

  • @alex_it,


    Hello Alex,


    I believe this question has been asked, but I didn't see your specific response to the question. Have you tried a different guitar? When you hook up a different guitar, are you getting the same issue? If not, then you can be pretty confident it isn't your KPA. I know you want to get it working with your new Rocketfire Strat...but the possibility exists that it is some issue intrinsic to your Rocketfire Strat (e.g. wiring, pickups, shielding, etc.).


    So, to cut to the chase, are you able to duplicate the anomalous behavior using a completely different guitar connected to your KPA?


    Cheers,
    John

  • So I finally downloaded and listened to the clips. This is definitely stratitis. I have it to a lesser degree on some profiles with my new Custom Shop strat, mainly the medium gain TopJimi stock profiles. It occurs mainly on the middle and bridge pickups. For some reason, it is only provoked by certain profiles. I can use those same profiles with another of my strat-type guitars with no symptoms whatsoever. A quick Google search will advise you of lowering your pickups, increasing string height and even checking for any shims in the neck joint!

  • @alex_it,


    Have you tried a different guitar? When you hook up a different guitar, are you getting the same issue?


    Cheers,
    John


    Yes, with other guitars I don't hear this kind of noise. Just a bit with my PRS in single coil split mode, but it's almost imperceptible. It certainly does not annoy me and in the mix you can't hear it.


    This Strat is the most treblish guitar I have though.


    So I finally downloaded and listened to the clips. This is definitely stratitis. I have it to a lesser degree on some profiles with my new Custom Shop strat, mainly the medium gain TopJimi stock profiles. It occurs mainly on the middle and bridge pickups. For some reason, it is only provoked by certain profiles. I can use those same profiles with another of my strat-type guitars with no symptoms whatsoever. A quick Google search will advise you of lowering your pickups, increasing string height and even checking for any shims in the neck joint!



    Thanks,
    I thought Stratitis concerns some kind of wobbly sound, like two notes together with one slightly out of tune. I had a Strat that behaved like that above the 12 frets of the g string, but didn't produced the noise described.
    I'll try to lower the three pickups but I'm afraid that I won't solve the problem.
    In the neck joint there's no shim, actually it's very tight to the body.


    Unplugged, I don't hear any strange sound. The ring modulator effect is audible by completely removing the bass frequencies.

  • Tried to lower the 3 pickups to the pickguard level, I still hear the noise..


    Probably poor wiring and/or shielding of the pickups. I mean, you have definitely pinpointed that it is the specific guitar that is the problem, not your KPA. I would re-solder the pickups. If that doesn't work, I would replace the pickups. At the same time, you should look at shielding the pickup cavity...assuming you want to stick with true single-coil pups. Personally, I would toss them, and go with something like Dimarzio HS-3s.