JP-8000 Master Restoration and Blue LED Mod (FULL TECHNICAL VIDEO) シンセサイザー復元

[@TheScreamingFrog916]

I've had mine since the 90s. In storage for most of those years. But have been playing with it again, for last three years. In great shape, except was taking longer and longer to boot up, make sound. I found a schematic, and figured out which cap it was, replaced it. Next time I have problems, I'll refer to this video, and replace the rest of the caps. Thanks for sharing this info. Subscribed :-)

[@tonydunford6760]

Absolutely top notch job! Your JP looks totally stunning! The blue LEDs are a really nice touch. My JP, which I have owned from new, is undergoing a similar resuscitation process right now, she has had her keyboard contacts cleaned and new 105 degree electrolytics. I had to disassemble and restore the stereo volume pot (as I could not find a replacement). Also she has new tack switches and rotary pots. I am about to fit 10K slider replacements. The slider pots have 0V one end and 5V on the other, the wiper goes through a 100R to a 74HC4051 analog multiplexor input, then to a buffer op-amp and then finally to an ADC input, so am thinking 10K should work with the same resolution as the original 20K? Great video, very informative and logically laid out. A true professional and complete perfectionist at work. Liked and subscribed! Thank you! BIG love from Techtone in the UK. P.S. My pitch bend and modulation controller stopped working after a battery change. If any one else gets this problem here is the solution: 1) Turn on power while holding [OSC2 SYNC], [-12dB/-24dB] and [FILTER TYPE] to enter Test Mode. Wait until display indicates "[1] MIDI Test." 2) Press the [3] button to display "[3] Bend Mod." 3) Push the bender lever left fully and gradually return it to the center. Press [LOWER]. 4) Push the bender lever right fully and gradually return it to the center. Press [UPPER]. 5) Push the bender lever to the MOD position and then gradually return it to the original position. Press [KEY MODE]. 6) When the '*' appears on the display, press [UP]. 7) From the previous display, press [4] to display "[4] Ribbon." 8) While pressing down on the left edge of the ribbon controller, press [LOWER]. 9) While pressing down on the right edge of the ribbon controller, press [UPPER]. 10) While pressing down on the center of the ribbon controller, press [KEY MODE]. 11) When the '*' appears on the display, press [UP]. 12) Turn off the power of the JP-8000. (Thanks to BevBKeys for this solution)

[@TwistedGridStudio]

I'm not sure on the 10k vs 20k, but be sure to come back here in the comments and let us know!. Sometimes you just have to go for it and give it a try!

[@tonydunford6760]

Hey, thanks for your reply, I have now fitted 10K sliders in place of the original 20K sliders and can confirm identical control operation.... All good... Yay!

[@TwistedGridStudio]

@@tonydunford6760 Excellent! I hope this information will benefit others! Thank you for sharing your findings.

[@reybarr8670]

Wow. Your efforts are mind blowing. I hope you get paid well for this restoration.

[@TwistedGridStudio]

Thank you

[@arjanv]

hi, just wondering, which LCD did you use?

[@TwistedGridStudio]

I purchased a blue backlit display from an eBay seller (glitchscience). The description was for a JP-8080, but it worked on the JP-8000 after some mild trimming of the upper case.

[@Kurztakt]

What display did you use to replace the old one?

[@PvKAmsterdam]

Amazing restauration! Do U have a more detailed specs overview for each capacitor used?

[@TwistedGridStudio]

I do, please visit www.bendinggrid.com and shoot me an email there. I'll send you a link to the specs.

[@PaulvanKessel-xq8vv]

@@TwistedGridStudio Great, just have send you a message

[@WalterGalindo]

Excellent restoration, im glad you have a unit that you feel comfortable with, i do feel that some of the stuff was unnecesary, like replaciog the IEC socket and some of the output jacks, i get the mains but not the control ones, and the midi ones only im sure were just an asthetic touch.

[@majri5000]

Hi, what wolud be first to check when Midi In does not work (Out is fine)? Appriciate your feedback.

[@TwistedGridStudio]

Sorry for the late reply. I would check the where the MIDI input plug is soldered to the board first, to see if there are any hairline cracks in the solder joint.

awesome video

[@DustonsSounds]

Very educational video! Thx 🙂

[@TwistedGridStudio]

I'm glad you enjoyed it

[@ultimatefab]

good job !

[@pentacle9783]

Gogeous Restoration! Can you let us know what LCD screen replacement you utilized & what modifications were needed?

[@TwistedGridStudio]

LCD from Ebay. "Blue Backlit LCD Display for Roland JP-8080 Synth Repair Replacement Mod" sold by "glitchscience". Had to trim the inside of the JP-8000 upper casing to fit. Dremel.

[@pentacle9783]

@@TwistedGridStudio Thank You Friend

[@ClementsAudio]

Any possibility of you uploading that sweet folder with all of the schematics and parts? I'm having the issue where my unit only powers on once in a blue moon. Usually it won't boot up and only has the green blocks at the top of the lcd. I'm pretty sure it needs to have all the elec. caps replaced. This video is excellent by the way! I've had my JP8000 for about 14 years and I haven't been able to use it in the past 3 :(

[@TwistedGridStudio]

If you provide a way for me to share the files with you I can do so. Contact me at our page in Facebook for Twisted Grid Studio via message with a dropbox or similar file sharing link and I can dump the files into your box.

[@ClementsAudio]

@@TwistedGridStudio you’re the best!

[@ClementsAudio]

@@TwistedGridStudio I sent you a message on your FB page

[@TwistedGridStudio]

@@ClementsAudio Sent you a DB link. Good luck!

[@audiovolts9577]

@@TwistedGridStudio Hi, Thanks for your info in this video, i'm having all the usual symptoms on one i just bought and have an 8080 too with issues and would love to get the files you patiently researched too, i'd be glad to donate to your patreon for your troubles. Thanks Al

[@aizoyurei]

Looks awesome. I'm currently in the process of looking for someone to change all the capictors in mine. Luckily all the slides, etc work, but seeing this video got me thinking about full restoration. I saw the LCD on ebay and was thinking about doing that mod but now seeing all the blue LEDs (and blue being my favorite color) makes me want to go that extra step. How much would you charge to do this to my JP?

[@aizoyurei]

Also for the OCT LEDs, how does that work? Are the LEDs like two stage or something or is it two separate colors for the -1/-2/+1/+2 buttons?

[@TwistedGridStudio]

I would charge too much, because it's a major PITA and I wouldn't want to do it again. Lol.

[@trco422]

@@aizoyurei It looks like he used Di-chromatic LEDs similar to the originals, but different colors.

[@ClementsAudio]

Ha! Aizo! What's up friend from real life?!?! My JP won't power up and I need to replace the caps. Hoping to find the parts needed to fix this bad boy up!

[@kaesori4685]

Looks Superb & great documentary. I replaced my LCD but it still becomes jumbled after a few minutes to the point where its just jibberish. Can you enlighten me as to which cap to change out please? Thanks a bunch in advanced.

[@TwistedGridStudio]

Have you changed the battery?

[@kaesori4685]

@@TwistedGridStudio Yes, yes I did. I should note the previous screen was going thru the same flaws so I ended up changing the LCD screen unnecessarily. Im thinking it has to be one of the caps. The other cap I replaced definately gave me clearer sound and free from distortion. Any ideas perhaps?

[@TwistedGridStudio]

@@kaesori4685 Download the JP-8000 service PDF. Page 13. It talks about checking Q8, IC1 (Pin number 1) on the main board.

[@kaesori4685]

Hmm, You think it's an IC Chip over a cap? Thanks for checking it out.@@TwistedGridStudio

[@TwistedGridStudio]

@@kaesori4685 Try to run the Jp8000 in diagnostic mode and run the display test if you can. It's in the service manual and just a few button presses

[@antoniosardara1000]

A cosa possono servire i LEDs blue???

[@prestonostra]

EXCELLENT video! Hey my JP-8000 wont save patch or performance changes anymore. I tried swapping out the battery, but no luck. Everything else works great. I hit write, I get the "Completed!" message, but the patch is the same before the modification attempt after a power cycle. Gracias for any ideas I could pass on to a tech! thanks!

[@TwistedGridStudio]

The JP-8000 has a self diagnostic mode. Google search for JP-8000 service pdf. Go to page 10. Do the memory test on your keyboard and it will indicate which item is the problem. It also has a list of where each component is on the circuit board for each error code. Then you refer to the circuit board schematic to see where it is on the board physically.

[@reiherreracl3459]

hey can you share the files you showed?

[@alanmarcero]

Great vid, thanks for the info. Thankfully mine has no issues so far, only a dead battery I replaced a few years ago. That restored JP8000 looks awesome with the updated LEDs. Do you know if JP8080s are susceptible to the same audio issues? I would guess the hardware is the same, for the most part...

[@TwistedGridStudio]

Yes the hardware is very similar, but different configurations on the board. This blue screen will fit the 8080 model with having to trim the casing of the synth. The JP-8080's are newer therefore the caps are newer. It's likely that as they age similar issues with sound output may arise.

[@jetset808]

don't the blue LEDs have a bigger voltage drop? isn't that going to mess things up ?

[@Pintosonic]

He explains it in the video, he had to change the resistors in line with the leds to a lower value so that the current remains the same.