The glue dries out, and the sticker falls off.
Using the key production milestone we know (serial #100,000 in November 1990), you can estimate your M1's production date. The table below provides a general guideline for estimating the production period of your Korg M1 based on its serial number range. Korg M1 Serial Number
Early units are more prone to standard aging issues. The rubber contacts under the keybed may require more frequent cleaning, and the factory internal backup battery (CR2032) is guaranteed to be dead if it hasn't been replaced. Early firmware ROM versions (such as v1x or v2x) are common here. Late Era (High Serials) The glue dries out, and the sticker falls off
: Serial numbers ranging from 000100 to approximately 050000 . These units feature the earliest firmware versions. Early units are more prone to standard aging issues
It's worth noting that vintage units often have dead internal batteries, which can cause them to lose their factory sounds. If you discover this, you can find guides online for replacing the battery and reloading the original data, but knowing your serial number is the first step in this restoration journey.
If you are looking for the serial number for the (Legacy Collection), this is not found on the hardware, but rather, as a Korg Forums post explains , on the black piece of paper included in the plastic bag with the manual.
: Press and hold the INT , CARD , and COMBI buttons simultaneously while powering on the unit. The screen will display the internal firmware version. A low version number indicates an early-production chassis.
