Korg Forums

[mattf]

I recently bought an used pa4x and it's my first Korg keyboard and my first with aftertouch. Problem is, I am unable to hear the after touch doing anything.

I factory restarted it and upgrade to 3.1, the factory reset again and choose the big band brass 1 as in one of the demo videos on YouTube, but applying more pressure to the keys after they are playing does not have the same effect as the joystick up(modulation) or any effect at all.

The after touch is not off under global settings, I tried different modes there as well and none seem to do nothing (different curves). It is enabled under sound eddit -> keyboard assembly as well!

The keys don't seem broken at all, the keyboard was "new". It seems very conserved without any scratches so I don't think every single key lost sensibility or whatever could break on it. How could I even test this to be sure?

[karmathanever]

Not all sounds have aftertouch (A/T) configured so
try the harmonica DNC sounds - these have A/T configured to "bend" the notes.


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PA4X-76, Karma, WaveDrum GE, Fantom 8 EX
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## Please stay safe ##
...and play lots of music
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[mattf]

I tested some dnc sounds but only on some of the guitars I can slightly notice some difference, that would be acting as a pitch bend, but is too small.

[mattf]

I see no difference at all pressing the keys with more or less pressure after they are played with the harmonica dnc1 at all.

[karmathanever]

That's a shame Matt

You may need to get a service guy to look at it for you.
I can't really think of anything else to try...

I wish you good luck with it

Pete
_________________
PA4X-76, Karma, WaveDrum GE, Fantom 8 EX
------------------------------------------------------------------
## Please stay safe ##
...and play lots of music
------------------------------------------------------------------

[mattf]

I am looking at it. I dissembled it today and tested the ends of the cable of the aftertouch strip and it is there, clean and working. The resistance varies when I apply pressure over the keys.

I started printing the midi events send by the keyboard on my pc and I noticed something suspicious. The control 11 (0xB in hexadecimal) keeps sending the value 127. I didn't find nothing that triggers that controller. 1 and 2 were the y+ and y-, 7 was the channel volume and 16 the ribbon controller. What is 11? Is it the aftertouch? I didn't find a korg midi implementation/specification that showed what controller the after touch is supposed to take. Can anyone share this info?

Another hypothesis is that this is somehow disabled in some hidden menu. Does this keyboard have that secret maintenance mod triggered by holding some keys while powering up? Like the mz x500 has with power up + intro + tone (or something like that, now I forgot ).

[musiccankill]

As it seems the strip is working and you have some technical knowledge so lets see..
There is an aftertouch calibration option in the test mode but you have to be careful not to get anything else out of calibration.
_________________
~~~The best keyboard for any player is the one that fits his/her needs!~~~

Korg keyboards owned now: PA5X 61 ,PA300, Triton extreme 61, Korg 707, Trinity plus

[mattf]

I did the calibration and tested with both high and low weight or pressure. It now works but in a very weird way, by printing the midi messages seems that the aftertouch is getting on a minimum of 80 and never gets back to 0 after the key is released. This is for the soft 3 setting. If I turn it off then it gets back to 0 after touching the "after touch" again.

For it of the after touch curve configs it either doesn't get high enough or keeps going down to a value that is not 0. Is there any calibration that can be done on the normal keyboard menus or anything I could be missing here?

I think I will end up having to replace that strip.

[Korghelper]

CC11 is normally ‘Expression’, most likely the foot controller input if set to swell.

I think CC13 was reserved for channel Aftertouch, iirc.

[mattf]

So after some trial and error I managed to calibrate it in a way that using hard2 the aftertouch goes back to 0 after releasing any key. Problem is it goes to a maximum of 12 (sometimes 20) only with maximum pressure, which is very low (in a range of 0-127 it should go). I can correct this by raising the value of anything that uses AT a lot (Like the AMS for pitch bend or modulation, setting it to 12 makes it go one tone up since 12/127*12 is about 1).

Could not find anything else that can calibrate or set the AT curves more properly. I think I will need a new strip but doesn't seem those are sold separately. Is there any one from another korg keyboard/synth that would fit on this 76 keys model?

[mattf]

One thing I don't get though is why aftertouch doesn't go back to 0 even though the strip is cutting the current? Isn't this how this was supposed to work? Is there any deeper factory I could do?

I made a test short circuiting the two ends of the aftertouch strip connector on the PCB but and it did show 127 on my midi printing meaning maximum signal and this was never reached by simply putting pressure on the keys or not even with many keys simultaneously (which does produce higher values since there is less resistance on the strip!).

I am not sure if i should replace the strip or this is a software problem. Or maybe something on the keybed PCB?