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deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

HI,

I have noticed digital distortion when my volume is bit before than 12 o'clock and up…

Can you suggest me what board has been damage?

This digital distortion coming from all rom/ram sounds on all outputs 1-4 + L/R + Headphones

According to the kronos service manual it should be boards

Klm -3002 – main board – which has the DAC connected to AUDIO BOARD KLM-3005 – maybe DAC chip is damaged?
Klm -3005 – audio board

1. What do you think and what are the prices for each board,
2. Is there any core charge for damaged board?
Thanks

SanderXpander · Platinum Member Joined: 29 Jul 2011 Posts: 7860

As far as I understand it the main volume is an analog pot directly connected to Main L/R and Phones. It shouldn't be able to cause/affect digital clipping at all. Additionally, it shouldn't affect the output levels of individual outs 1 through 4.

Just saying this because it may impact your conclusions about what the exact cause of your issues is.

deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

i don't think that the volume potentiometer is causing the distortion, the volume potentiometer seems to works well
i think its one from the boards...

anyone from korg japan can help here?
OPs?

SanderXpander · Platinum Member Joined: 29 Jul 2011 Posts: 7860

Then what do you mean with "when my volume is bit before than 12 o'clock and up…"?

There is nobody on here from Korg Japan as far as I know. Dan is from Korg US R&D but doesn't really comment on technical issues other than to refer to the official service centers, which is what I'd also recommend beyond this point.

danatkorg · Posted: Mon Oct 26, 2015 3:00 am Post subject: Re: i don't think

deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

Edit

Forget about the sentence "volume is 12 o'clock...."

This distrotion can be heard when ALL SOUNDS ROM/ RAM is on standard volume output level from the kronos mixer...(means, i see it on Kronos Screen)

dB from main/ hp output from the kronos is below -4 db

AND IT HAPPENS ON ALL 1-4 outputs aswell which aren't related to the volume control, so its ABSOLUTELY RELATED to damage of the DAC or ADC on the main board or something on audio board

Dan , can you ask there how to verify what's damaged exactly

deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

partsisparts doesn't have any replacement board parts for kronos

deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

partsisparts.com doesn't have any replacement board parts for kronos can you tell me where i can get replacement parts?

danatkorg

miljantoto · Joined: 28 Sep 2011 Posts: 21 Location: Belgrade, SERBIA

SanderXpander · Platinum Member Joined: 29 Jul 2011 Posts: 7860

I'm not sure what you're talking about here, I'm sure individual units can have issues. As I wrote to deliad, the analog volume control has nothing to do with the DAC and he then explained that it happens regardless of the analog volume setting. Maybe there was some confusion there for you too?

mintjamman · Posted: Tue Oct 27, 2015 6:35 pm Post subject:

Out of interest is sound handled by the motherboard or does the Kronos have its own seperate sound card ?

deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

Again, i was wrong in the way that i explained it

i have some defect in somewhere in the board

and i changed my words!, this distrotion problem doesn't related to volume knob or volume at all

it's digital distrortion because of problem in the MocASP which looks a part from the am1806/am1808 processing unit that talks with all the converters

please put attention that the spdif is not part from the analog in/out dac's and is not part from klm-3005 which is the Analog Audio input / output board

which means this problem coming from the klm-3002 main board, from this Signal processor on the am1808/am1806

attached the schematic of the kronos 1 which explains it all

geoelectro · Posted: Tue Oct 27, 2015 10:57 pm Post subject:

I believe you are going to have to deal with a service center. I service keyboards, (not Korg) and I can order any board that's available from my companies. I can tell you the retail price and availability.

A Korg SC should be able to do that for you as well. Typically if a part is installed by a service tech it is warranted, but if a user installs it there is no warranty. The biggest problem with this kind of repair is getting the correct part. If you buy a board on an educated guess but are wrong, you may end up having to pay for it anyway. If a SC does it they can usually avoid that scenario.

Geo
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deliad · Junior Member Joined: 06 Jul 2009 Posts: 59

but anyway, can you tell me the price for klm-3002 board?

PartIsParts doesn't have it and korg.com forward to them

korg UK doesn't sell parts anymore...