Korg KingKorg
This time a truly special instrument landed on my workbench – the Korg KingKorg with a tube in its output stage. It came to me straight from a major, well-known service center. Despite being declared “fully operational,” its owner was still hearing obvious distortion at higher volumes – especially on organ and string sounds. At first I was skeptical. I checked the audio path, replaced electrolytic capacitors and op-amps – no result. I even tested the digital I2C volume controller and the complex multi-voltage power supply. Everything seemed fine, but the issue persisted.
I had to return the instrument, feeling unsatisfied.
Two months later, though, I contacted the owner again and asked if he could send it back – I had one more idea and was willing to try at my own cost. This time I went deeper into the electronics, took extra measurements and replaced the 24-bit Burr Brown DAC right before the audio section. The problem was gone!
