My Jupiter 6 just died.. Any ideas why?

[jonnypowell]

My beloved JP-6 has died in the ass..
The thing still powers-up and i can change presets, but no (proper sound is coming out) I've tried both outs and the head-phones and all I can hear is this ocassional faint sound, but it seems to be the same sort of sound each time - a ultra quiet blip.

Any ideas?

[Tibbon]

Hmm. Can't get the filter to self oscilate either? Likely not the voices then, or the filter.

Something with the amp envelope section/ampliflier/adsr would be my first guess.

Or, even though it powers up... that part of the power supply is working, but not another part? I don't have a schematic, but maybe the +5VDC part is working, but not a +9VDC section of the power supply? I'm not sure if it's a single voltage power supply, or something different in there?

I built a x0xb0x recently and it had a 3.3V section and a 5VDC section if I remember right (for digital and analogue parts)

[jonnypowell]

I'm thinking it might be the cpu..
I bought a Jupiter 8 a week ago though, which will fill its shoes (when it arrives!) but am worried this could cost a lot to fix..

[Cojo]

Internal battery gone maby?

My Oscar is acting the same way. Have you tried to change ALL the sliders after you've powered it up to see if you can get any sound from it?

[James Meeker]

Maybe a connection went bad, the VCA's fried, or there's an output transformer/amplifier that died. Could be just connectivity between modules?

I'm not a tech, but owned a few Jupiter 6's. I'm guessing the repair shouldn't be too bad. The board opens up pretty easily and is well laid out internally. Generally speaking those boards are pretty rock solid so getting it fixed is definitely worthwhile.

Oh, just remembered... I had a Prophet 5 go weird on me in 2000. Just outputed low level white noise-ish sounds. Turned out the power supply was feeding the Z80 microprocessor "brain" improper voltage and it caused the CPU to lock up. On digitally controlled synths like the P5 and JP6 this could be a possibility.

Power supplies tend to be the cause of many analog synth woes.

[teknosmoker]

Here's a high quality .pdf scan of the Jupiter 6 service manual.

Sorry to hear about your sick JP-6. I can't think of any other ideas to suggest, other than what has already been mentioned.

Best of luck!




-T

[jonnypowell]

Thanks heaps for al your help guys!

Gonna take it in to get serviced next week.. Not sure if I'll keep it yet.. Depends on how different the sound is to the JP-8.

[Tibbon]

If it doesn't end up working, i might want it

[nofi]

I don't really see the point with speaking to non-electronic tech people about what their gear's faults could be..... at the end of the day even if I could say "it's component x" if you're not an electronics type, it'll never get fixed by you anyway.

But I'll take the time to say if the synth powers up and you can change presets, it's NOT going to be the processor at fault.... it's not the VCOs or envelopes that take button presses off the front panel and change the LED display, is it?

I'm thinking the fix will be quite trivial. So just take it in for repairs. Pete's musicians market (newtown) can arrange to have it fixed up by a couple of different synth techs in sydney, depending on who is available. Steve Jones is the best, but seems to get whisked away pretty often to be INXS keyboard tech when they're on tour.... so take the time to specify that if he's in sydney right now, it should go to him.. but really, anyone at all will be able to fix your JP6's problem.

[jonnypowell]

Originally Posted by nofi

I don't really see the point with speaking to non-electronic tech people about what their gear's faults could be..... at the end of the day even if I could say "it's component x" if you're not an electronics type, it'll never get fixed by you anyway.

But I'll take the time to say if the synth powers up and you can change presets, it's NOT going to be the processor at fault.... it's not the VCOs or envelopes that take button presses off the front panel and change the LED display, is it?

I'm thinking the fix will be quite trivial. So just take it in for repairs. Pete's musicians market (newtown) can arrange to have it fixed up by a couple of different synth techs in sydney, depending on who is available. Steve Jones is the best, but seems to get whisked away pretty often to be INXS keyboard tech when they're on tour.... so take the time to specify that if he's in sydney right now, it should go to him.. but really, anyone at all will be able to fix your JP6's problem.

I'm not seeking to "fix this myself". Just wanted to know if anyone has encountered a problem like this with their JP-6, and if so what was at fault.
I'm just worried it's gonna cost a lot to get fixed..

I spoke with Steve a few weeks ago and he was busy with INXS, but said I'm welcome to bring it down to his house way down south.. I think I'll just take it to Phase Engineering as they're pretty close to me. i also have a TR-808 that needs a look over.

[rachel]

Steve is now living in a new place. I got him to do my Jupiter 6 Mod panel
which had stopped working last year. He had gone over the rest of it it and said mine was working OK, since it had originally had a service when the Europa board went in. Apparently my
JP6 has silver paint sprayed inside it for some reason. I would like to know what
the problem ends up being. I would be so annoyed if my JP6 went out on
me, since I am using it a lot. I still have to send Steve my OSCar but have to arrange a courier!


rachel

[jonnypowell]

Originally Posted by rachel

Steve is now living in a new place. I got him to do my Jupiter 6 Mod panel
which had stopped working last year. He had gone over the rest of it it and said mine was working OK, since it had originally had a service when the Europa board went in. Apparently my
JP6 has silver paint sprayed inside it for some reason. I would like to know what
the problem ends up being. I would be so annoyed if my JP6 went out on
me, since I am using it a lot. I still have to send Steve my OSCar but have to arrange a courier!


rachel

He seems to be pretty popular.. Phase is kind of easier for me, but last time they took 6 weeks to service my Pro-5..

[nofi]

Originally Posted by jonnypowell

Just wanted to know if anyone has encountered a problem like this with their JP-6, and if so what was at fault.

Ok then. well in that case, it's most likely your rotary timing crankshaft chain that's bent a spoke, which caused a gasket to blow, and oil to leak out everywhere, in turn causing your envelope generators to lose traction.... happens all the time with these models. messy.

Originally Posted by jonnypowell

I'm just worried it's gonna cost a lot to get fixed..

it won't.

Also, any decent repairer can be asked to estimate total repair cost in their first hour you pay for, before running off and doing $2k worth of repairs. They will be able to give you a much better idea from looking in your synth and measuring voltages, than some random internet person will by reading about the problem online.

Originally Posted by jonnypowell

I spoke with Steve a few weeks ago and he was busy with INXS, but said I'm welcome to bring it down to his house way down south.. I think I'll just take it to Phase Engineering as they're pretty close to me. i also have a TR-808 that needs a look over.

I'm sure phase will be able to make it live again, too.

[jonnypowell]

Originally Posted by nofi

Ok then. well in that case, it's most likely your rotary timing crankshaft chain that's bent a spoke, which caused a gasket to blow, and oil to leak out everywhere, in turn causing your envelope generators to lose traction.... happens all the time with these models. messy.




it won't.

Also, any decent repairer can be asked to estimate total repair cost in their first hour you pay for, before running off and doing $2k worth of repairs. They will be able to give you a much better idea from looking in your synth and measuring voltages, than some random internet person will by reading about the problem online.



I'm sure phase will be able to make it live again, too.

Sorry dude. next time I encounter a problem I'll be sure to keep it to myself ok!

p.s. Steve is gonna take care of it..

[triez]

Originally Posted by nofi

Ok then. well in that case, it's most likely your rotary timing crankshaft chain that's bent a spoke, which caused a gasket to blow, and oil to leak out everywhere, in turn causing your envelope generators to lose traction.... happens all the time with these models. messy.




it won't.

Also, any decent repairer can be asked to estimate total repair cost in their first hour you pay for, before running off and doing $2k worth of repairs. They will be able to give you a much better idea from looking in your synth and measuring voltages, than some random internet person will by reading about the problem online.



I'm sure phase will be able to make it live again, too.

Very true, a JP6 should not be an expensive repair. It is extremely rare for serious catastrophic failure in Roland gear, I have been servicing Roland gear for 23 years and have yet to see anything like a power supply failure going over voltage.

The JP6 has a master CPU board and 2 slave CPU's on the voice boards, and quite a few Roland custom IC's which are still pretty easy to source. If the machine is making no sound out of the headphone jack as well as the line out then that mostly leaves out the Jack board because the line outs and the headphone outs have different op-amps, (IC3 for the line out, IC 4 for the headphone out), BUT half of IC 4 is used in the volume VCA circuit, so a dead IC4 on the jack board could be the problem.

The first thing to try is to put the machine in panel mode and making a patch with the sliders and buttons to see if it is just a flat battery dropping the memory. If you get a sound then the battery needs replacing. If it does not work then, the next step would be to open it up, check the power supply rails (always the first thing in any repair), and then start looking at the various points in the analog path with a scope to see if the VCO's are changing pitch with the keyboard, the filters are opening and closing in response to the sliders, the voice VCA's are opening and closing in response to the ADSR controls, and if the final VCA is passing signal.

It is unlikely to be a voice board, as they would both need to fail together, so it is more likely the CPU board or power supply. It is quite common for bridge rectifiers to fail in Roland and Yamaha gear of this vintage, giving a rippley power supply which stops everything.

A leaking battery can cause a lot of damage, I haven't seen this in a Jupiter yet though, most of them seem to have the original batteries in them which is truly amazing.

[elwrongo]

Hi Triez

I just finished reading your post above from 2008! I know this thread is very old but it's very interesting and informative and I was hoping may hold out some hope for my dead JP6.

Mine turns on and all the red lights are on but there is no sound or any action whatsoever. I took it to a repair guy here in Perth and he said the mainboard is cactus. However you post seems to suggest that that is unlikely. What do you think?

Do you know any knowledgable synth repairers in Perth? Thanks Rick