Microkorg, one key reacting slowly

[Oscar_William]

Hi

One of my Microkorg keys is reacting slower than all the other keys. Like two seconds after i press it it reacts.

I did a clean recently because a few of the keys became messed up. I need to do this every couple of years when the contacts inside get gunky. It has always worked before. Just put some kontakt cleaner on a cloth and clean the contact board. This time one key just won't work properly.

This key is not dead, but it reacts slower. Are there two different contacts for each key and the one that reacts to the instant press is dead? Where can I find the source of the problem?

Many thanks!

Cheers
Oscar

[OpAmp]

Hi Oscar,

That is a kind of strange effect. Sounds like a cap that needs to be loaded (but there is no cap around).

Google the service manual, it may help you a bit further in debugging the issue.

As all keys are arranged in a matrix that is scanned and only as one key suffers from it it must be something really specific to that key.
A key has indeed 2 contacts (a make and a break one - not sure how exactly this works) hidden in the rubber switch. The purpose is to determine the velocity of the key hit by measuring the time between the 2 contacts closing. So maybe one of the diodes is broken or the rubber switch itself?

You may also look at the midi output generated by the broken key, especially the velocity may be interesting and reveal a clue.

Good luck

[Oscar_William]

Thanks you for the reply!

I will purchase a new key contact board. And see if it helps.


Will post my result here

[Oscar_William]

Update: I won't be changing the contact board because it's half the price of a new Microkorg, so I might just get a new one in that case.