Korg Forums

Recently I've discovered a low level background noise out of all of my Korg Kronos output jacks, including the headphone jack. I borrowed a friends Kronos for an upcoming show. And his Kronos has the exact same problem. Same for all patches, and out of all outputs. I'm wondering if there is an easy fix for this... Any help, much appreciated!

My first suspicion would be a ground loop. Can you reverse or isolate the ground? Hopefully you are using a UPS?

I have tried lifting the ground on direct boxes etc... The only way I've been able to at least attenuate the noise is using the graphic EQ and bringing down 16k. But of course that is also effecting the sounds.

Check that the input level controls on the rear panel are set to Line and minimum.

Most likely to be the analog inputs on the rear panel. They can be a bit noisy if the gain is set high. If you're not using them, then you can disable them in the global audio options, or the audio tab of any program or combi that isn't using the global options.

Don't forget to check your cables too.

If you have nothing connected to the Kronos but its power cord and good headphones, do you hear that noise?

If so, it's likely a power related issue. Or it could be EMI from a flourescent light, a MacBook power brick, a nearby motor (fan) or other electronics (wireless mic or router).

If no buzz with just headphones, try one cable at a time to narrow down the culprit.

Must be the audio ins. My Kronos is the most quiet piece in my setup.

I use the optical out straight into my AI and it’s perfect.

Lots of good tips here that I haven't thought of. Went into global and adjusted the audio inputs and that has definitely made an improvement on my Kronos. I will try that again tonight on my friend's Kronos in the pit. I love the idea of using the S/P DIF optical out but unfortunately my interface (Presonus AudioBox) has the optical ins/outs reserved for ADAT. Very grateful for all of your responses. Thank you! I will update after rehearsal tonight on the noise level.

Ok on my friend's Kronos changing the audio input settings in global completely solved the problem. Mine is running much quieter, however, there is definitely still an audible noise. Not enough to bother the sound guy, but it's still there. I don't think it's a power issue, because I can hear the noise at my home studio, and also in the theater. I'm wondering if it could be an accumulation of dust.. Any other ideas?

Accumulation of dust on audio connector contacts can cause noise, and output level fluctuations, but noise would only be heard if there is a DC offset present, either on Kronos Outs or sound system Ins and normally requires the connectors to be moved for the noise to be heard, producing a "scratchy" sound. It's good practice to periodically give these connector contacts a good clean with contact cleaner.

The Kronos Outs are normally very quiet relative to Line level signals, which means using the Kronos' main volume control generally set to 12 o'clock or higher. Connecting the Kronos to a Mic In would be a bad thing, since these inputs expect much lower signal levels.

A noisy internal power supply could cause audio output noise issues.

Certain amplifier modelling effects intentionally introduce noise, as part of the effect, as will distortion effects, and some Combis have some background noise by design, even when the keyboard isn't being played.

If the low level noise can still be heard with main volume set to minimum and only headphones connected, with everything else apart from mains power disconnected, and no celular/mobile phones or active transmitter mast in the vicinity, then suspect an internal power supply issue.

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Most of the time that I've heard noise, it's gain staging issue....like if I run into my K10 monitor with it on the Mic setting instead of Line.

I have noticed it makes a lot more noise while booting up, but then when it's done it goes quiet.

I tried using the optical out but was unsuccessful. My interface (M Audio fastrack pro) has a coax S/PDIF. I bought an optical to coax converter but could never get it to work in my DAW. I believe the problem may have been the FastTrack Pro drivers being able to match the settings of the converter box. I just ended up using the balanced 1/4" analog in for recording and it was fine, I just thought for digital recording the S/PDIF would have been ideal.

Again thank you to you all on this forum. I developed a hiss and just put up with it for a while until sound checking a show recently the sound guy said the hiss was extremely loud. Remembered seeing this thread. I had messed around with Yvette vocoder and forgot. Set line input and reset gain back to minimal and fixed!!! Thank you!!!