Trying to get rid of excessive noise

    Hello all - this isn't really a profiler problem as I had the same issue with my Axe-Fx II - but since i Just got the Kemper this weekend and have been playing all weekend - and have the itch to play again - I need to get this solved. I run the Kemper the same as the Axe - direct to an RCF NX 12 - guitar direct into the Kemper. I have been wrestling with the most horrendous noise and can't seem to get rid of it. I did manage tonight to figure out that my iMac is part of the culprit. I only get the issue with the guitar volume turned up - so the pickups must be catching all the EM this iMac is putting out. I don't think it's being coupled via the power outlet - althoughI guess it's possible. The iMac goes into a Monster Power - power strip and the Kemper right now is directly plugged into the wall - as is the RCF albeit a different outlet. Has anyone else had this issue? How did you solve it? Even with the iMac off I'm still wrestling with some remaining noise - that is more than just amp hiss. Any recommended solutions? Isolation transformers? Filtered UPS? I gotta get this solved or it's going to drive me crazy.

    Ok guys - in the hopes of getting people interested in this thread - and because I need to learn some tricks of the trade anyway - I just took some time to figure out first - how to hook the kemper up to the iMac to record. I'm going from the main out (left) into my Firestudio mobile. I used to have Reaper but I guess it's been so long since I've opened itthat it's not compatible with the current MacOS version I'm using - so I gave up on that. Will tackle that another day. This is what happens when you let 5 or 6 years go by without even touching your guitars.


    Really - I just want to play because I need to put what little playing time I have into relearning how to play - getting my fingers to cooperate and relearning songs I used to know. But I gotta figure this noise thing out - it's horrendous.


    I modified my hookup today - now sending the monitor out to my FRFR speaker - so I can record from the main. I made my first ever soundcloud recording just in the hopes that you guys might have some solutions for me. I'm not experienced at recording at all - and even though I paid for Reaper - I never bothered to learn to use it really. So in this case - I just used Garage band. Dragged over a backing track for one of the songs I was "relearning" today - and did a quick experimental recording. Excuse the clams - as I said - it's been a while but hopefully you can hear what I'm dealing with. I also stopped playing a couple of times to adjust the GB volume. First time trying to use it as well. It's really frustrating. Now - let's see if I can figure out how to embed a SoundCloud recording.


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    Wolfgang standard with Duncan JBs in bridge. Tried another guitar with same results.


    Not a CRT. It's an iMac. 2011 model.


    Interestingly the noise doesn't really vary with angle or distance - although I haven't moved far away but it actually gets a lot less if I put the guitar right up to monitor. Almost as if it's almost perfectly out of phase.


    Amplitude doesn't 't really vary much otherwise.


    Im surprised I'm the only person who has encountered this. Maybe I have a really bad EM radiating iMac.

    Different guitar. Did that - but maybe tomorrow I will try another.


    Cable- checked that.


    Room - well- I had this same issue in another house.


    I could try using a guitar cabinet bit wouldn't expect much difference.


    Possibly could use spdif- if I have a cable here. Will check tomorrow. Based on the limited number of people chiming in with similar issues I'm thinking I may have to find a different computer. Which is a shame - I like my iMac.

    The RCF is an active speaker but I get that noise - even with it off. Pretty convinced that the majority of this is coming directly from the iMac. Does anyone else use an iMac? I guess my only fix is a new computer - which is not cheap. I could mess around with various shielding ideas - but have my doubts. The noise is so bad though that it really makes it impossible to play - or to at least enjoy playing.

    Any way for you to try with a different computer to rule that it's the mac?


    Also try a different usb/fw port for your interface, sometimes those cause noise. Another thing that I can think of is do you have any external devices connected apart from your audio interface? I had lots of noise from my usb hard drive when it was connected to a certain usb port at one time.


    Found this thread: https://discussions.apple.com/…/2259725?start=0&tstart=0


    This happens on ALL of the new iMacs. It's a grounding issue.


    The new iMacs introduce a ton of noise into the ground pin which can be heard on any high quality external speakers. The best solution is to plug your iMac in through one of these: http://www.ebtechaudio.com/humxdes.html


    See the following posts on this issue:


    http://discussions.apple.com/message.jspa?messageID=10857870


    http://discussions.apple.com/message.jspa?messageID=10748818


    http://discussions.apple.com/message.jspa?messageID=10748807

    Hey brother - I appreciate you taking the time and effort to research that. The last three links don't work for me but the first thread link did. The thing is - I don't get that noise just during play back. As I've posted this thread and walked through some troubleshooting ideas - I've become more and more convinced that I have a leaky iMac. Meaning it's leaking EM and my guitars pick it up. I am going to try your suggestion this weekend of using my MacBook Pro and seeing what improvement i get. I expect to get a LOT. I even chatted with my little brother tonight - who actually makes a living as a pro musician and also does some producing (he lives in Nashville) - he uses an iMac and no issues. Pretty convinced that this fan or perhaps its the HD - don't know - but whatever it is - it's radiating and my guitars are picking it up and it's just the worst. Sucks because outside of that - this iMac has been an awesome computer. I remember retiring Windows PCs after a year or two and I bought this in 2011 and it's still fantastic.


    Thanks again for the effort. Much appreciated.

    I have discovered that if i take the noise gate intensity up to about 9.0 it helps immensely!!! Does this seem abnormally high to anyone? I always shied away from noise gates - even on my other amps because of sustain kill.

    Quote from nakedzen

    Maybe your guitars need their pickups repotted since the noise seems to be coming from there? You said you had them laying in storage for years before this, maybe the wax has dried out and isn't doing the shielding anymore.


    You can take them to a luthier to get them potted or do it yourself, it's not really rocket surgery.


    https://www.premierguitar.com/…w_To_Pot_Your_Own_Pickups

    That's an interesting suggestion that hadn't even come close to crossing my mind. Although - I'm not sure how the wax assists in shielding - is it conductive? Your point about them laying around for a long time is well taken though - I hadn't given any thought to something deteriorating on them over time. I'll have to mull that over. To be honest - I'm probably too lazy to repot - would probably be just as happy using new pickups.
    I listened to a YouTube demo from another thread here - and was just marveling at how noise free that tone was. I'd be pretty damn happy with this Kemper if I can solve this noise issue.
    Gotta say - this noise gate is impressive. Even though I think 9 is too high - and do feel some tone/sustain suck - considering how jacked the NG is - it's not bad. Nice to not have to look at other parameters and just turn one knob. Good for lazy guys like me.

    Just thinking out loud there^ it's not necessarily the cause.


    You can remove the pickups and take a look at the wax, it's around the coils. If it's still soft it should be fine and problem lies elsewhere. The wax works against feedback and noise.


    If the pickups aren't potted at all, then the problem may or may not be the missing wax, some pickups don't benefit from it.

    Thought I'd update this thread just in case anyone else finds themselves dealing with this. As suspected - it was a fan - the graphics card fan. Evidently a known issue for that year Mac (not so much the EM leakage) but just that the card and fans have issues. I could have had them tear the iMac apart and replace it for $600 on a Mac that Apple considers "vintage" in 3 months or - consider modernizing. Downside of iMacs is they're a bitch to work on. I decided to get a new MacBook Pro - for several reasons besides just the fan. It's so awesome to hear dead silence on the Kemper now. I can finally really start auditioning rigs and enjoying the machine.

    If am near my computer, I can get all kinds of awful noise, no matter what my guitar is plugged into. It gets much worse depending on the angle between the computer and the pickups. I wasn't sure what on the computer was causing it, but it may be my gpu fan, as well. I wonder if there is anything I could buy/make to stand on the floor, between the computer and me, to block out the interference.