Found Solution to the EMX-1 and ESX-1 Knob Jitter-Issue

[OMONOS]

This fix makes sense, I can't wait to try it! I got a used EMX1 off ebay and the program encoder is f'd, and usually, the display jitters at random parameters when I'm not even touching it. But I've lived with it for so long, its still a great piece of gear. I was thinking I needed a new encoder (which I'm having trouble finding). If this fixes all of the above, I will be so grateful! I'm ordering new tubes too!

[DrHoo]

Search ebay for 'silicone rubber sheet'. go for the 1mm. Maybe there's some other material too if you dig deep enough.
Just thinking that it may be less prone to fire & seems like a good electrical insulator choice. Views anyone ?

It strikes me too that there's no need to isolate the entire internal size is there ? I mean, isn't it one specific area that is the culprit ? Just wondering.

Much respect for the descovery in the first place.

[Discom]

Hello, I had this same problem, so I opened up my EMX and the CN1B ribbon popped right off! I put the ribbon back onto the pins, but it was all messed up and inoperable, so I had the crazy idea of crazy-gluing the ribbon to the pins; which worked for a while, but ultimately all the parameters got stuck at 30 (friggin' system failure). I got frustrated and tore the ribbon off out of sheer anger for having to deal with bad build-quality in the first place.

So, my question is if a new CN1B can be soldered onto the pcb, not that I'm capable of such a task, but if I brought my EMX to a local electronic repair shop, would it be possible for less than $100, new ribbon and all? If not, where can I find a new pcb + ribbon for less than $100? Sorry if this is the wrong thread haha..ha.....*quietly sobbing in the backround*

[stereoman]

Cheers for this, recently bought an EMX used off ebay, was gutted when it started jittering, figured i'd bought a dud, anyway did the baking sheet fix today, tightened all the screws and thoroughly cleaned everything, been running perfect for the last 3 hours or so, well chuffed

[synthtrip]

LMFAO, just got a pair EMX and ESX on ebay, there was a knob jitter disclaimer, but from what I've seen, it usually only is a problem very rarily

to my disappointment the EMX had SEVERE knob jitter and even worse none of the parameters would go below a value of 8 (or -53 for the center detent pots)
I felt a bit mislead by the "mild' knob jitter that was advertized to me

so after doing some research and coming across this thread I decided to open the EMX up to see what I could do

to my astonishment the previous owner had already done the baking sheet hack some of the masking tape had come loose and I think created a short (is adhesive conductive??)

put it back together, plugged it in, knob jitter isn't immediately obvious and values go down to 0 (or -63)
I guess only time will tell

one question though, are the bodies fot the ESX normally a little bronzer than the EMX bodies (not the faceplate, the under body) I suspect my ESX was previously owned by a smoker, just curious

btw, long time EMX user, new to the ESX, I f*ck*ng love it, 2 great machines

[MichaelAlois]

Hey, fairly recently I started experiencing the dreaded 'knob jitter' on my Emx sd. It mainly occurerd on the modulation section and the effects edit knobs. I have just ever so carefully performed the wax paper technique and at first. Delight. But after a day or so.. boom.. the effects knobs just break out in full knob jitter action.. so frustrating!!! Anyway... my friend suggested spraying the curcuit boards in crc clear urethane coating to insulate it all. I'm absolutely clueless when it comes to thus stuff and I'm not sure if it's a good idea, or not. Please help me out or add anything you can. Thanks. Mike

[drum4life42]

Ok, I just purchased a used emx sd version which is in mint condition. Came in the box with the manuals that seemed to be untouched. I was so excited until I found out that it had this arpeggiator issue... Every time I used it, it would change my parrameters on the cutoff, eg, pitch, etc, etc. I tried the parchement paper fix that has been posted and it worked until I turned it off and then back on again... 

I found that there were three little peices of solder that had pierced through the paper on the depth side of the board making contact with the power switch because they are too long. I then folded 2 peices of electrical tape and added 2 more strips, a total of 6 layers so that the solder could not pierce through and short out on the power switch. I also slightly tightened the black screws which hold this board up... They were fairly tight already. 

Anyways, its been day one, about 4 hrs of play and and I havent had any issues with the arpeggiator affecting any of the parrameters. I hope that this is another alternative fix to this problem because its extremely annoying and uninspiring when your machine tells you no. 

I will post an update once I put it through a few days of testing. Hope this helps anyone having the same issue. 

PS. Thank you dr nibbert for giving me the information to try the operation. Cheers.

[robbieboysmith]

I've had this problem for years. I was excited to see this post and immediately took my esx apart and applied a piece of wax paper to the bottom of the circuit board. I put it back together an no change. I covered the sheet with electrical tape and still no change.

I did replace the resonance knob a while back and that completely fixed the problem with that knob. I think the only real fix is to replace the knobs that are causing the problem and ill be replacing the rest of my problem knobs this week (even though its an enormous pain in the ass).

I'm amazed that there is no official word from korg on this issue. Would be a fantastic instrument if it weren't made with carp parts.

[robbieboysmith]

I've had this problem for years. I was excited to see this post and immediately took my esx apart and applied a piece of wax paper to the bottom of the circuit board. I put it back together an no change. I covered the sheet with electrical tape and still no change.

I did replace the resonance knob a while back and that completely fixed the problem with that knob. I think the only real fix is to replace the knobs that are causing the problem and ill be replacing the rest of my problem knobs this week (even though its an enormous pain in the ass).

I'm amazed that there is no official word from korg on this issue. Would be a fantastic instrument if it weren't made with carp parts.

[drum4life42]

I havent had any issues since I placed that electrical tape down onto the back off the depth knob solder.

And yes robbie, I agree with you that its kind of a joke that korg has not responded with a solution to this problem. It makes me very weary of purchaseing any of their new electronics. I love korg products because they are unique, sound great and are quite user friendly. But at the same time, I also like reliability, exceptional build quality and customer support.

[drum4life42]

So, upon further use of my emx... I transported it to a friends and it instantly started doing the same thing. I decided to file down the excess solder on the bottom of the depth, speed, pitch/glide pots. Fingers crossed, it hasnt had that issue since.

[rmaruani]

Hey guys,

I did the baking sheet fix and it worked for a few months but it recently started going crazy and I can't seem to fix it, any of you guys have an idea of how I could fix it ?

Thanks