Korg 01/W “no sound” repair
A few weeks ago my 01/W started sounding “hissy” and distorted, and the output level dropped audibly. After a short power off it recovered without further action. But then, on the next day, all analog outputs were dead.
When I opened the housing, I found two leaked electrolytic capacitors on the mainboard’s sub-PSU for the DAC and analog stages. This ±5 volts sub-PSU with two 100 mA voltage regulators is disposed behind the ±12 volts stabilisation circuitry of the main PSU and supplies stable and noise-free local voltages.
The caps C95 and C96 had ruptured, and the sub-PSU and even more distant parts were spattered with electrolyt. And the really bad thing about leaked electrolyt on a printed circuit board is, that it causes corrosion and damage of metallic parts and circuit traces. See the “overgrown” capacitor C100 or the diode D3 on the photos for an impression of how this affects and proceeds.
To clean this type of mess, I prefer cotton swabs heavily soaked with isopropanol (isopropyl alcohol). There’s no need to spare with the isopropanol, it does not do any harm to electronic components and evaporates without residue. And the cleaning should be repeated a few times with fresh swabs.
What has been left over from the “acid attack” on my 01/W did not look dramatic at first. I replaced the two evil caps, connected the mainboard and powered up the 01/W, but there was no sound. While measuring I found that the negative leg around the IC52 (79L05) was operational, but IC53 (78L05) floated around at 0 volts on it’s output and input. Then I noticed that one of the C100 capacitor’s leads had been “eaten” by the acid and – more important – the +12 volt trace below the lead had also been etched away.
So I replaced C100 and patched the broken trace by scraping off a bit of solder resist and bridging it with solder. As you can see on the photos, I also replaced IC53, which stabilised at 4.5 volts and not 5.0 volts. Of course, it is not state of the art to replace an SOT89 SMD component with a TO92 through-hole component, but firstly it would have taken some amount of effort to get the SOT89 variant, and secondly it is yet a robust and well-functioning replacement in this case (fitting pinout and leads, no thermal or mechanical aspects to be considered).
The other capacitors on my 01/W were apparently in a good condition, so I would not estimate this to be a general case of “bad-caps-alert” for all the other 01/Ws around. However, in the recent past I read about 01/W owners on the net, who have asked for advice on their whatever natured “no sound” problem, and so this article may give you a hint towards the possible cause.
Update (October 07, 2008):
J-man sent me photos of his “no sound” repair on a 01R/W, the rackmount variant of the 01/W. He writes: “I’m sending you the pictures of my fixed 01R/W, before and after the repair. [...] I’m sorry about the quality of the pictures before the fixing: they are quite blurred, expecially one of them.”
Hello Hajo,
vielen Dank für die super Anleitung. Ich habe heute auch meine 01/W reparieren können.
War das gleiche Problem. Ich mußte zwei Elkos und zwei Widerstände ersetzen.
Die besten Grüße,
Peter
Excellent work & a really effective help to everyone…!
Thanks for all of the info. I also suffered the same problem on my 01W. No sound first, eventually no display. I found other websites that claim solutions, but you have it right on. It is caused by bad electrolytic caps, google search “leaking electrolytic capacitors”. All of the electrolytic caps bearing the same mfg. in my 01W leaked. I changed every one on the circuit board, got my display back but still had no sound. I used it as a midi controller for a couple of years until I found your website. I changed the voltage regulators like you did but still did not have any sound. I checked every trace and component that the electrolyte leaked onto. I later found it to be R142 and R143, right next to the regulators. Service manual says they are 20 ohm fused resistors. Very hard to find unless you are buying thousands of them. I ended up using 20 ohm resistors and it has been working fine for the past 3 months. Money and time spent after seeing your site: The regulators 10/$1, Service manual $15 on ebay. Resistors from radio shack and 2 days of work. A local service guy wanted $500++ to repair. If your 01W has no sound, and no display, open it up and check for leaking E caps. If there is no sound, check the area near IC52 & IC53.
THANK YOU HAJO for helping me fix my 01W
I forgot to mention, I got the voltage regulators from ebay, and all of the electrolytic caps from Mouser electronics (www.mouser.com). They had all of them, even the NP (non-polarized) ones (8) near the output section in addition to the regulators. They dont have minimums like others. Hajo & Mouser are the best!!!
Hi Sam and Hajo. My 01R/W was lying silent and dead in a flight case, since I found this web page… I opened it up and immediately found 4 broken capacitors, with lots of electrolyt all over the printed circuit. I see that there are some other components that suffered severe corrosion: a couple of polyester capacitors and a couple of resistors. There is no way to see their values, of course. Tomorrow I’ll check the board carefully to see if there are other damaged components. I tried to find the service manual on eBay but I didn’t find one yet. Do you have it in PDF format, and would you sell it to me directly ?
Thanks in advance for your attention. You both did a fantastic job, and I hope to follow your steps and bring the 01R/W back to life. Nuff respect
Well, after a couple hours of work my 01R/W is fully restored in perfect shape… and it sounds better than ever ! OK, maybe it’s just my imagination..
Anyway, I replaced the 5 exploded capacitors: C100, C101 and C110 by the power supply 5-pin plug, C29 and C30 by the audio output. All of them were 100 microfarad/16v: I decided to raise the tolerance of the new ones to 63v (C100-C101-C110) and 25v (C29-C30). I measured all the other capacitors on the board, and they seemed OK.
I had to replace one of the 22 ohm fused-resistors mentioned by Sam, R78, because it was burned by electrolyt. The smaller I found at home was 1/8 W… It’s a bit squeezed between the caps, but it works…
Of course I carefully cleaned the board: luckily enough just a few traces were damaged and it was easy to restore them.
Now I just need to know the value of C102 and C103, the small polyester capacitors in parallel with C100 and C101. I guess that 10nF should work, anyway if somebody could check the service manual and tell me about… Thanks in advance.
I’m so happy to have my 01R/W back again, for a number of reason: you couldn’t imagine how grateful I am to you guys. THANKS A LOT !
PS I shot some pictures after and before the job: if you’re interested please let me know.
Sam and j-man,
thanks a lot for your positive feedback and the detailed additions you gave with it. Your knowledge is welcome, and it will definitely help and motivate other 01/W users to get their boxes back on track.
Please send me your pictures and maybe personal information via email to 01w[at]kessener.net if you agree to have them published here on this site. This also applies to external links to your website(s).
Regards
Hajo
Found the manual, thanks to Yahoo’s 01W user group (http://launch.groups.yahoo.com/group/korg01w-list)
C102 and C103 value is 0.1 microfarad. Of course… I should have guessed it
Hajo, I’ll send infos and pictures as soon as possible. Thanks again for your unvaluable work, and also to Sam for his great contribution.
I am having the same problem with my Korg 01w. My keyboard has been laying dorment for several years. Everything works except no sound coming out. I took it to one repair place (Sam Ash actually sends their keyboards there to get fixed) and they told me it’s almost unrepairable. To get parts for it will be very difficult and expensive and will only result in the same problem eventually. From what I’ve heard, Korg used certain capacitors in the 01w which cannot handle the heat and over time they explode. So part of what this guy is telling me is probably true but now I found this site and see that some of you had no problem fixing it on your own. Unfortunately for me, I have absolutely no knowledge or skills to even think about attempting to fix this problem. I’m from New York. Does anyone know anywhere or anyone I can bring my keyboard to, to get fixed. I was actually going to throw it out a few months ago and held off because I just couldn’t imagine throwing out something I paid over 2 thousand for. This site has given me some hope, if I can only find someone with enough know-how to fix it for me. Any help will be appreciated. Thanks.
Frank, I’m in NYC. I had taken my dead 01/w to Rogue and they wanted $500 ++ to repair several years ago. I too was gonna toss it out but couldn’t do it. Thanks to Hajo and this site I didnt. I am an audio engineer and owner of a sound company. I can but dont repair equipment because of the time necessary for troubleshooting. I will send my email to Hajo and maybe sometime after this 2008 year, (I am booked til the end of the year) I can help or guide anyone in NYC what I had done to my 01/w.
One more thing, My repaired 01/w has been working flawlessly since my repair. Only problem I have now is the “clunk” from worn out felt under keys. Does anyone know where I can get replacement felt? or know the exact thickness it should be? I’ve seen replacement felts for keyboards and read that thickness will affect the action and velocity of the keys. Thanks
Let me just say, It ALWAYS pays to get a second opinion. After the repair place (that Sam Ash uses to fix keyboards), told me that my keyboard had capacitors which leaked and was basically unrepairable, my keyboard has sat in my house for two years untouched. Last week I was going to throw it out, but for some reason I just couldn’t bring myself to doing it and I went online to do more research on this problem and found this site. Now I don’t know why I didn’t think about this in the beginning, but I then went to the Korg website and found a listing of Korg repair people close to my location. I called one up, brought the keyboard over and in 5 days it was fixed for just over 200 bucks. The real kicker was that the problem I was initially told, was not the problem. I had no leaking capacitors. I forgot what it was, but something broke inside that usually happens when you don’t use the keyboard for awhile and its left in a damp area. That is exactly what happened. I didn’t use it for about 6 months and was kept in my basement. One day I decided to use it and everything worked except no sound coming out. Just to think, I was going to put this out by the curb and throw 2500.00 dollars into a garbage truck. The keyboard is as good as new and sounds wonderful. And I’m also just remembering that those scumbags at that initial repair place charged me 40 bucks just to look at it. Anyone having a problem, it may be worth going to the KORG website and looking up local KORG repair people. They obviously know these keyboards better than anyone else. I’m proof of that. Thanks for responding Sam.
I had the “no sound” and “sticky key” issues with a 01/W. searched the web a lot and found Hajo’s blog. the name was familiar to me, so i decided to ask the one i had in mind. and yes, it was Hajo. we live in the same town.
talking to him, made me replacing two elkos but still no sound. he then took a look on his workbench at home and found a tiny smd resistor next to the elkos. replacing it (R142 / 18 Ohm) and the elkos i used (35V – i was replacing the originals with 16V first) – the 01/w made sound again.
while half the device was partly apart, i decided to go on.
next was the keyboard, removed all keys, cleaned them, used hajos “Klüberpaste” and refitted them. as said by a comment above: its strongly adviced to remove the “activator strip” – at least, before you remount the single keys. its only 10 screws, but you wont risk demaging any of the metal-tongues of the “activator board” – i underline this hereby
next step was removing the key/lcd-panel. here its adviced to remove the huge metal-bar which sits partly under the psu. you have to partly unscrew some screws from the psu-holder – not totaly unscrewing them, just a bit so you can elevate the psu and remove the metal-bar quiet easily ( 5 or 6 screws on the psu, IIRC ).
next step was cleaning the key-pcb from dust and while thinking about using chemicals or replacing any key, we decided to replace them all.
afterwards I did connected the key-pcb to the mainboard and connected the display, to check, if all keys are working as expected. and yes, it was worth replacing them.
Next one: the lcd backlight. hajo ordered 2 panels, but unfortunatly one of them was defective – no light at all. the second one was working properly.
the good thing here: after unsoldering the back-light from the two soldering points, we were able to just drag the backlight out of its housing ( gently try to pull it out, a lttile bit forth and back ) – it was partly glued to the lcd-pcb. nothing got damaged. this way we didnt had to fully taking apart the lcd.
after fitting the new backlight and soldering it, we did a test, and there was light. no problems with any pixels, just perfect, i’d say
the reassembling took a while, but using photos i made while disassambling, i had a good orientation and could place all screws on its original place.
i also made some sketches of the postion of the screws on a paper – on each step: undersite, main-pcb, keyboard, key-pcb, activator-strip and -activator-pcb, lcd. placing the screws around the sketches on a free table. this was very helpful, when reassembling the device.
last update was the firmware. hajo got a capable burner, so the 01/w was refreshed from #31 to #62.
one last note: good tools are essential. starting with good screw-drivers, a desoldering-iron ( incl. some desoldering wire ), a good solder-iron/station.
Finaly I have to say, without this blog i never ever would have gone so far; maybe i should mention, the device isnt my own, a friend left it here, when he moved to another city; but i told him what happened meanwhile
Well, lucky enough to have hajo around. thats for sure a plus. a big plus.
thanks again, Hajo.
Taking care of the steps described at this blog and some basic skills in handling electronic parts makes it possible for you too
as said above, i made some pictures and told hajo about them, so he might use them in some sort of gallery here. hope they will help you too.
best ragards.
[...] following is a set of photos from Freshman’s 01/W refurbishment. In fact, his 01/W suffered from the “no sound” syndrome, the [...]
hey frank,
you said “something broke inside that usually happens when you don’t use the keyboard for awhile and its left in a damp area.” my audio outs have also conked out after sitting in a basement for a while: can you elaborate on exactly what broke in your case so i can look for it?
thank you.
-a
Hi Andy,
I do not know anything about electrical stuff so when this guy was explaining what happened to my keyboard and what had to be fixed, I had no idea what he was talking about. At the time I didn’t care, I was just thrilled that it was fixed and I didn’t throw it out. Looking at my receipt, he wrote on it “Repaired open layered traces.” According to him it was 2 1/2 hours labor and it cost me $216.00 dollars. I don’t know if that explains anything for you. What I do remember him saying is that this usually happens when the keyboard is not used for some time and is left in a damp area. That explained everything for me because there was one summer where I had my keyboard in my basement and I wasn’t home for weeks at a time because I was working on my vacation home. Therefore there was no dehumidifier going and I actually started to get mold down there. This guy told me that even if you don’t have the time or feel like using it, to put the keyboard on for a bit, once in awhile. I don’t know where you live, but this guy I got from the Korg website. The name he’s under is Santorelli Prof. Electronics 102 Park Ave Bayshore, NY 11706, [edit: phone number removed by Hajo]. Hope this helps you. Good Luck!
I’ve got an 01W/R. The display screen works, but is too dim to use on stage….repair shop says the whole display needs to be replaced….special order….expensive…any ideas?
Hi TJ,
neither special order nor expensive. See this comment for an explanation and maybe also this article for a few shots. Hope this helps.
Regards
Hajo
Hello Hajo.
Thank you for your site and your efforts.
I was wondering if you can help, or at least guide me in a right direction
The problem is with my Korg i2.
I left it on. When i got back to it whole power line was down.
Since then, when i’m powering it on – LCD screen shows the logo, with a crossing horizontal line (each time line appears in a different place) and inage dimms away, while backlight stays on and the keyboard is working correctly.
It’s also possible to see what’s on the screen, under the sharp angle.
I’ve been told that this problem might be caused by a simple replacement of a capacitor, responsible for the image stabilisation.
Anyway, I would apreciate any comment on this problem.
Thanks in advance
Hi S.D.,
although I’ve not yet experienced the behaviour you describe, it sounds as if the problem is located on the LC display itself. Check the capacitors on the LCD’s circuit board, see the following link for reference:
Blown cap on LCD of Korg 01R/W
Have a look at the other capacitors on the mainboard as well.
Regards,
Hajo
Thank you for reply, Hajo.
I hope you had amazing holidays
Back to the problem…
Surprisingly, capacitors on my LCD board looked exactly the same as at:
http://pics.studiorepair.de/Korg/01RW/EL_Foil/slides/Korg_01RW_LCD_Blown_Cap.jpg
I’ve replaced the “burned” (right) one but it didn’t help.
I’ll try to replace the second one (which looks fine), hope it will help.
In addition to that, i forgot to mention, that i have a weird “whistle” sound coming from the power supply.
I remember this sound (it was barely noticeable), even when keyboard was operating normally, but now it’s very loud.
S.D.,
the “whistle” you describe is the sound of the inverter that generates the AC supply voltage for the EL-foil (the backlight) of the LCD. The inverter is located on the power supply unit on some Korg instruments. There’s always some noise around ~400 Hz with this type of inverter, but when it starts to audibly “whine”, this is indicating a high load due to the dying backlight; the backlight will also be dim in this situation. I would recommend to replace the EL-foil, see this article for photos.
Regards
Hajo
Apologies if this is off topic, but I cant see other sites where my problem might get a reasonably sensible answer!
I have a Korg M1 and all outputs including the headphone output, sound distorted. The distortion is not constant, but stays for about one second after the key is pressed. It sometimes returns but not always.
Anybody have any ideas as to the cause? I’m aware that it’s an old keyboard and that parts are likely to be difficult to come by, but it would be good to know what is required to fix it.
D.
OK…a bit more info….it’s not the D/A PCB. I swapped the one from my M1R (which are both the same) and had the same result…the M1 is noise, the M1R isnt!
My own feeling is that this might be a preamp problem….basically, that the preamp is hitting whatever it’s given at 100% and therefore ultimately distorting…..OR whatever is going to the preamp is at too high a voltage, thereby causing distortion. When the sound decays to a lower volume, the distortion reduces. Just my own musings, mind you…nothing really to back it up…..
Oh….dont all rush to help!
D.
Hi Donal,
as you’ve already dared to swap boards, I’d recommend to check the +/- supply voltages on PSU output and op-amps. If possible, try to monitor voltages when distortion occurs.
Regards
Hajo
Hi Hajo,
Thanks for the reply. I’ll try that and get back to you on it.
Reagrds,
Donal.
Hi Donal,
I just had a look at the M1 service manual and noticed, that there’s an additional active (op-amp) stage on the output connector board KLM-1262 behind the D/A board. If the power supply is ok, then the error is likely to be found on this output board. Drop me a line, if you need the schematics.
Regards
Hajo
Hi Hajo,
I’ve had a look at the +/- voltages on PSU, and I get 11.7v each side regardless of whether it’s distorting or not. I also had a look on the 1261 and 1262 PCB’s and I get no variation from 11.7v. While i was at it, I removed the 1262 PCB for a visual check…nothing obvious to be seen…no popped capacitors or dry joints. In fairness, this keyboard shows no signs of having been gigged or otherwise given any kind of rough treatment.
Am I wrong in that I’m beginning to think that the distortion is probably eminating from the synthesis side rather than from the amplification side? I have an older, more worn (but working!) M1. I’m wondering if I should start considering a heart/main board transplant?
Thanks for your continuing help!
Donal.
Hi Donal,
one idea fom my side, before you start transplanting mainboards: hook an amplifier on pins 4..7 of CN13A and listen to the audio. If all four signals sound distorted, even if you disconnect CN13B, and if both 1261 DAC-boards behave the same, you may not be wrong with your theory. It would then still be interesting to find out, what is going wrong on the mainboard.
Regards
Hajo
Hi Hajo,
I hooked up an amp on pins 4-7. Only 4&5 had signal as the program I selected was only programmed to output on A&B, but both were distorted. I disconnected CN13A (it was easier to reach and would, i assume have the same effect as disconnecting CN13B) and there was no change.
Would a small audio file of a couple of piano notes be of any benefit in trying to diagnose the problem? If so, send me an email and I will reply, attaching it.
Regards,
Donal
I think I’ll give up on this and send the m1 to Korg for repair. .
I’ll let you know what the problem was when I get it back!
D.
Donal
I do have the very same problem. I’m not skilled in any electronics stuff but friends are… now I would be very happy if you could drop a line on what the problem really is.
I bought mine off ebay and the problem came up after a couple of days, at first it worked perfectly.
I hope Korg still has M1 repair, maybe there’s even a simple solution…
I live in Switzerland, hope I don’t have to ship my M1 around the world for that repair…
Thanks
Simon
Hi Simon.
My M1 was delivered to Korg UK on Wednesday 29th. I expect to hear from the shortly and I will post any information I get here.
Before I sent it, the repair person in Korg said that main boards are not available any more, but that it may be possible to repair the board at component level.
Regards,
Donal.
Thanks Donal!
I hope it’s not the Mainboard… That would be 250 $ thrown out of the window for me then…
Thanks
Simon
Hi Simon,
I just got the quote from Korg. It says “To strip and rework pcb, dry joints found on DAC PCB and main PCB.”
The cost is £60 plus carriage of £31.88 so including taxes the total comes to £105.66. As I live in Ireland, I think that this is quite reasonable. I actually sent the keyboard via post from Northern Ireland so that only cost me £23.
People tend to complain loudly when they do not receive good service, but in this instance I’d like to give Korg a thumbs up and say that I’m very happy with the service I’ve received. It’s been prompt, polite and efficient. Well done all.
D.
Hi Donal,
thanks a lot for your feedback and information, much appreciated, and also thumbs up for Korg and your decision to send your M1 for repair.
Regards
Hajo
where can i get those small chip capcitors from
and what is the capcitance value? c21, c19,r243, r142
Samuel,
the parts are available at electronic stores. C19/C21 are 100nF, R142/R143 are 20 ohms fused resistors, which were hard to find for me, so I replaced them with standard SMD resistors. Btw: You may get the schematics from the 01W group’s download section on Yahoo.
Regards
Hajo
I’ve got a loud annoying high-pitched whine coming from the PSU of an O1/W Pro. It seems like that’s probably the backlight issue, so I figure I should try replacing the EL panel.
Do you have any recommendations on what to purchase for a replacement EL panel? I’d rather not take the whole keyboard apart twice — once to figure out what’s in there, and once to replace it — if at all possible.
Hi James,
see this answer. For a replacement EL-foil, I’d recommend MIDI-Rakete, they ship worldwide.
Regards
Hajo
Hi,
I’ve got the same problem with the M1.
The sound is distorded. I Wan’t to check the sound just after the DAC but I’ve no service manual.
Some boby can send me that ?
Regards.
Damien
Hello,
I’m look around the web and find this place. I read some up messages in here, it’s very good information. But can not find schematic for Korg 01W/FD. I need help with Service Manual or Schematic for Korg 01W/FD so I can repair it. Anyone has service manual please help me.
Here is my email: [edit: removed by Hajo]
Thanks a lot in advance
Hi Trung,
the service manual is available at the download section of the Korg 01/W Yahoo group.
Regards
Hajo
HELP!!!! Just finished installing a new backlight. Works fine except that there are no numbers displaying….just a beautiful , bright green glow! Also (even worse), I get no sounds.
I thought I was very careful about re-installing everything, so I’m really concerned that something else crapped-out. Guess I’ll have to dis-assemble everything all over again. Sigh……….
Anyone have any thoughts?
O.k……a lesson well learned. Turns out I forgot to plug in a multi-pin connector! I guess after 7+ hours of benchwork I was getting a little impatient.
My thanks to Hajo and all the posters here who enabled me to undertake this project.
I purchased the backlight from Telesis, P.O. Box 19015, Anaheim Hills, California, 92807 U.S.A. for $35.00 which included a pdf instructional cd.
Hi BigBillKahuna,
thanks a lot for your feedback and clarification. All the best to you and your Big Kahuna Band.
Regards
Hajo
Hello, Hajo! A friend has asked me to look at his Korg Pa-60. No sound. I’m just reporting this in case anyone else has similar problems with a pa-60.
The midi out works fine. This model has external audio inputs, so I can confirm that the amp and speakers are working OK.
The I/O board has plenty of garden-variety electrolytic caps, and no visible problems. It’s connected to the rest of the unit by four cables. One sends signals to the power amp. Another goes to the panel volume controls. The remaining two are ribbon cables from a board encased in a steel shield, which I infer is the “main board.” One of the ribbon cables is from the “main board digital” and feeds the midi, which as I said is working fine. I scoped the signals at a nearby 7404 and I can see digital activity when I press a key.
The other cable connector is marked “main board audio signal.” The connector has 20 pins. (I don’t understand why you’d need a 20-pin ribbon cable to carry audio signals.) One of them has a steady AC signal, regardless of whether a key is pressed, and the others don’t show any activity on a scope. A couple of them carry DC.
Presumably the main board power is OK, because the midi is working. I took the shield off and looked around, but I couldn’t see any obvious problems. Almost all the caps on this board are uniform in size, rather squat, flush to the board, and encased in shiny metal with one side painted black.
Just reporting in, although of course if you have any advice I’d love to hear it.
I have the main board out again. On the underside are four large proprietary chips labelled “BANK0H, BANK0L, BANK1H, BANK1L.” Each of them has a whitish bloom at one end. The bloom also appears on the PCB, and under high magnification I can see dark blotches on or around the traces. Humidity damage does seem to be a possibility. Redcall that the board is encased in an envelope of solid metal, so it wouldn’t breathe well.
Is it advisable to clean this off with isopropyl alcohol for a better look, or should we just take it to a specialist as is?
Hi Jim,
a cleaning is recommended and worth a try, in my opinion.
Regards
Hajo
Hi Jim,
the 20-pin ribbon cable: does it transport analog or digital signals, and where did you locate the DAC circuitry?
Regards
Hajo
HI. I no longer have the synth. I did clean the suspicious-looking parts with rubbing alcohol, most of it came off. The tracks appeared to be intact; I double checked with an ohmmeter and they seemed OK. But this did not revive the sound. I had to reassemble it to find this out. After I got the unit back together, I thought I might as well just return it to the owner. There was nothing simple and obvious that I could do, especially without a schematic.
I wasn’t reading any signal at all on most of the 20 pins. You’d think they’d carry digital, but the circuitry on this half of the destination board (the IO board — the other half is MIDI circuitry) consisted mostly of clusters of discrete components and a couple of 8-pin ICs — more what I’d expect to see in a preamp. That’s what puzzled me. Maybe that’s all you need for a DAC though — I’ve never worked with them.
Thanks for the reply!
hi Hajo,
thx for your infos. a few days earlier i got my 01w/fd repaired (the stick keys), and after that i found the ivory key on the rightmost doesn’t sound anymore. can u figure out the reasons?? thx a lot.
Hi guys, I nee the service manual for 01/W and 01/W pro X. Can someone point me in the right direction or [text & links removed by Hajo]? My 01/W pro X died last week and I need to repair it……help is apprectiated regarding service manuals. Thanks in advance for any hint. Nice blog……….!
Hi Aykman,
the service manual is available at the download section of the Korg 01/W Yahoo group.
Regards
Hajo
hello hajo, i am a korg 01/w user and looking for help to repair the unit. right now i am facing problem with the sustain/damper pedal not working. I undersand there is an ic controlling the damper switch. do you know whece can i get the parts for that? thks in advance.
Hi Kyzee,
how or why do you suspect an IC to be damaged? I’d recommend to check the obvious first, which is the pedal itself with cable & plug and also the DAMPER jack and respective soldering joints.
Regards
Hajo
I just turned on my Korg 01W pro, which was sitting in the garage for about a year. It was working just wonderful and then i hear a “pop”. What can that be. I have turned in on and off, tried different cables, re’inialized it and still no sound. I tried headphones and that doesn’t work. I live in Dallas Texas. Is there a repair place that can fix it or maybe I can if pointed in the right direction. I have only used Korg for the past 25 plus years and will stay loyal.
Thanks,
Sparky
Hi Sparky,
sounds like you witnessed the death of resistor R142 or R143. Have it fixed by a trustworthy technician.
All the best,
Hajo
Hi,
me again. So, my Korg 01/W pro X is working approx. 5min without problems but after that slowly distortions appear until I have very loud noise & distorted.
I am planning to open my Korg after 24.Dec and check for leaky caps and damaged parts.
One guy told me that hissing sound (distorted sound) can also be caused by the faulty E-Foil or damaged FD Drive? I do not really understand how the FD drive can influence the sound?
My other questions is: Did someone update the DA Converter by Korg service? What improvements did you get? Or is this part of the ROM update?
Thanks for any answer
cheers
Aykman
Does anybody have the exact part number of the “fused resistors”? Or what is the “german” term for it?
Hi Peter,
the german translation is “Sicherungswiderstand”. My search for a replacement part ended with the conclusion, that SMD type fused resistors are expensive and/or only available in large quantitites.
Regards
Hajo
I own a KORG 01/W ProX, I am only interested in one sound and one sound only and that’s the Grand Piano sound. The guy I bought it from programmed it with a bunch of layered voices and I can’t figure out how to remove all those layered voices, I’ve tried downloading to users manual and I tried resetting it back to the default settings, back to how it first left the factory, but I am totally clueless. I can’t even find the Grand Piano voice, I’ve looked in both banks A & B, but out of 256 voices or however many voices there are I just didn’t see Grand Piano, but I have a feeling it’s hiding in there somewhere. So, please help me with my KORG 01/W ProX – please. Thanks.
Hi Angel Sing,
try these links on how to initialize the 01/W and use the “preload” function:
http://www.sweetwater.com/sweetcare/ts/detail.php?Index=16001
http://indra.com/~cliffcan/01faq.htm
Regards,
Hajo