Korg Forums

Xenophile · Senior Member Joined: 14 Nov 2017 Posts: 349

Over the last few days my ~6 year old Kronos2-61 started throwing intermittent “A problem has been detected” messages and/or spontaneously restarting. Coincidentally(?) I had just started playing with the sequencer to load backing tracks to play along with. This is literally the first time I have ever played with the sequencer, copied a wav file to the internal SSD and imported as an audio event. I can’t help but think something in the process of doing that somehow triggered the recent flakiness.

I have read that the most common point of failure on these machines is the power supply, but the fact that I had just copied a fairly large wav file (~6 minute stereo wav at 48KHz/16-bit) to the drive makes me think the SSD might be getting flaky… though I’ve read that is not a common point of failure.

So I expect I’ll open it up and re-seat the cables and memory. But I’m also thinking of replacing the power supply as well. I would like to hear about any experiences anyone might have had with swapping in a somewhat beefier Flex ATX power supply… I see that I can get 300-350 watt power supplies for $60-$70 USD, but the form factor is slightly different, with a built-in AC socket and power switch, so I’m guessing some DIY modifications would be required. So please share any stories you might have about this.

Also, if I should choose to replace the internal SSD… What tools have you folks used to duplicate the existing SATA drive? I know you can get stand-alone duplicators for under $100, but I would think that there are inexpensive PC- or Mac-based solutions using a couple of SATA/USB adaptors and some software… Would MacOS’s Disk Utility work for that? Maybe the UNIX-style “dd” command works on a Mac?

Please share your experiences. Thanks!

average_male · Senior Member Joined: 07 Feb 2011 Posts: 278

I have done both, swapped out stock SSD with larger/faster SSD and upgraded to better power supply.

For the SSD upgrade, please see this post (not my post but this is what I followed): http://www.korgforums.com/forum/phpBB2/viewtopic.php?p=801037&sid=1fdd3240a87313082eb9e438f031501f

For the power supply upgrade, yes, you will have some DIY tasks to perform, See this post which notes the power supply I used and what it looks like with the power supply lip off (lid needs to be on in final installation):
http://www.korgforums.com/forum/phpBB2/viewtopic.php?t=121491

some more details on the PSU can be found here:
http://www.korgforums.com/forum/phpBB2/viewtopic.php?t=126926

Xenophile · Senior Member Joined: 14 Nov 2017 Posts: 349

Thanks! That is really helpful information. There must be some other DIY stuff to get AC power from the connector on the back of the Kronos to the connector on the ATX Flex power supply.

Have you noticed any improvement in Kronos’ stability with the bigger power supply? I was looking at a Seasonic power supply similar to the one you used, but features something called “active Power Factor Control” for about $20 more. Not sure if that is worth the extra coin.

I was thinking that the “Problem has been detected… cycling power too quickly” message might be due to glitches on the POK signal from the power supply to the motherboard. I have my Kronos plugged into a UPS/power conditioner, so I don’t think line noise is my problem.

KK · Platinum Member Joined: 13 Oct 2016 Posts: 1422

Check the remaining free space on your disk as SSDs filled at 75% or more can bring problems.

average_male · Senior Member Joined: 07 Feb 2011 Posts: 278

Yea, at the time I was upgrading my PSU, the 300SUG was not available. That one is the Gold 80Plus where the one that was available, 300SUB, is Bronze. Both have high end Japanese capacitors, so better than stock.

For my case, I got the Kronos with the bad PSU (PS_OK was always low) so can’t speak to better or worse, but can speak to the quietness and cooling aspect , which where better in both cases (cooling based on other temp from users) But stable going forward.

One thing to note is checking with your Motherboard and what power features it supports, S2FC vs S3FC (IIRC, these are sleep modes?) The two models above differ in which features they support, where one supports one feature but not the other. https://seasonic.com/sug#modal (Overview section)

There was another approach PSU I was considering, pico-PSU, faneless,similar to this:
https://www.amazon.com/Mini-Box-picoPSU-160-XT-Power-Mini-ITX-Supply/dp/B005TWE6B8

Decided against it as I didn’t want to alter the power supply feed configuration of my Kronos. That is, the idea of accounting for the power brick, either being inside or outside of the Kronos and how to expose a power jack/receptacle and make life difficult for future owners and myself if the power adapter went bad. Having to drill and add such a jack or repurposing the existing power cutout in the back just would make everything look and feel “hacky” (hacked + tacky).

Xenophile · Senior Member Joined: 14 Nov 2017 Posts: 349

Begrudgingly bit the bullet and ordered the OEM power supply from Full Compass. It is expensive at $219 USD but I didn't want to spend hours fiddling with modifying the connectors and wiring harnesses. If I take it to a shop they would charge me $200 for the board plus another $200 labor. They told me to expect to wait 3-4 weeks for delivery. So I'm bringing my old Mainstage rig back on line for a couple of gigs. It sounds great, but there are so many things to plug in! Not to mention all the (re)programming I will have to do.