Korg Prophecy - issues (updated)

Greetings from Sunny Florida :sunglasses:

I have a Korg Prophecy keyboard that I’d like to bring back from “limbo”.

Issue #1 - I need to update the System ROMs to the latest (last) to version #20, since sysex cannot be sent back and forth unless this version is installed.

I purchased the EEPROM pair online. When I installed them the unit no longer functions past the welcome screen. I bought a second pair of EEPROMs, and I was assured they were tested prior to shipment.

When I power on the unit and hold the [EXIT] and [COMPARE] buttons down simultaneously, I can confirm the Prophecy is version 1.13.

Wondering if perhaps this system version needs to be updated before the new ROMs will function properly - hoping perhaps y’all have some information/documentation there since I can’t find anything on the interwebs.

Thanks in advance for your help!


P.S. Synth Wizards has changed my life, thank you!

One Step Closer!

So I found the bin files for a firmware update to the Korg Prophecy (v 1.7) and the files are named identical to the #20 ROMs. I think this will solve my problem, especially since the current firmware is v 1.13 - sounds like a pretty big jump.

Does anyone know how to upgrade the Korg Prophecy firmware? All I have is the bin files and I RTFM’d (read the friendly manual) the service manual and this process is not mentioned.

Thanks in advance for your help!


You need an EPROM burner and given you have ROMs already a UV ROM eraser (that is if your ROMs have a clear window under a sticker.

It’s a lot of faff, so if you know anyone with the kit already I’d get them to help. I did a Wavestation to EX conversion and I had to bend pins and solder wires just to flash the ROMs as Korg used some chips with slightly non-standard pinouts.

Thanks for your response, but I’m confused.

Are you saying that in addition to the two ROMs for the #20 upgrade, I also need to burn and install ADDITIONAL ROM(s) for the firmware upgrade?

If so, which chip(s) will I be replacing?

The Prophecy is from the age of synths where there is no flash memory for firmware. So the code is stored in ROMs. Often the factory ones are non-reusable. So you get reusable ones, which are typically in a ceramic packaging with a clear window on the top (there are some electronically erasable ones, but they’re less common). What you do with an EPROM is place it under UV light to erase it using an EPROM eraser (or UV nailpolish curer will do). You then get an EPROM programmer and program the chip.

It can be a lot of faff and an EPROM programmer will set you back about £30 UKP. Some need adaptors for larger ROMs, meaning multiple passes.

Some EPROMs are hard to get hold of and there’s a lot of recycled chips on ebay and places. You end up having to grab a big bunch of them and then weed out the bad ones.

Here’s a review of the one I use.

Thanks for taking the time for the information and explanation.

Unfortunately, it appears what I need to find out is simply lost information in 2020 - so I’m going to put the original EPROM set back in and dump the Prophecy since it’ll work fine that way - just without SysEx.

I understand how EPROM burners work and since I have two sets of #20 ROMs that work perfectly fine in someone else’s Prophecy I don’t see how RE-doing what I already have will be helpful to me.

The only difference I can determine is that my System is 1.13 and the other Prophecy is 1.7. My Prophecy didn’t update to 1.7 when I swapped ROMs, so if you’re correct - then I’d need to identify and replace another EPROM. That information seems lost in time, so it’s looking like I should simply give up.

Thanks for taking the time to answer me though - much appreciated :slight_smile:

I have a prophecy that I updated the eproms on. Its super plug and play assuming you know where the 1 pin is on your board and they flashed the eproms correctly. I have purchased eproms that I installed correctly but weren’t loading. Switched them around and they were fine. The person who burned them didn’t maintain consistent orientation. Anyway, the one thing to say about those prophecy’s is that there is latency in the midi no matter what eproms you’re running. It can be a total pain on most days.