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breakdown on my Eden WT800
- Thread starter bartoli
- Start date
Most likely the issue, but it's a job best left for a qualified tech. I've seen these boards cook the traces until theres not much of anything to solder to.
- Feb 12, 2006
- 61,037
- 5
- 220,961
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Right, then the trace opens up and a new problem emerges. Especially if it's the shunt regulator trace, an over-voltage condition throughout the preamp.
I think talkbass should set up an IA to automatically reply this actually.
Unfortunately Qualified techs are virtually non existent around these parts...
- Feb 12, 2006
- 61,037
- 5
- 220,961
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Can't help you there, it's what happens when qualified techs are no longer appreciated enough for them continue developing and refining diagnostics skills enough to remain in the industry.
As stuff becomes more complicated and cheaper to manufacture it no longer makes sense to get things repaired.
I know of 2 GB shuttle 6.0's with bad preamps. Are schematics available? Drawing one by hand is prohibitive in terms of time.
- Feb 12, 2006
- 61,037
- 5
- 220,961
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Schematics are only available to Fender authorized service centers with a valid NDA on file.
As far as diagnostics go, it’s rare to find a bad preamp, but there are a variety of things that can be bad based on what may have happened to the amp.
The factory flat rate service program ($85 USD) is available globally, though shipping outside of North America will increase the cost considerably.
Shuttle 6.0 preamp boards are still available as a factory service part.
Unfortunately unqualified techs often masquerade as qualified techs too. Example - I recently sent the logic board out of a friend's failed MacBook Pro to an outfit that specializes in specific generations of Apple products. I didn't want to risk damaging it being an 'unqualified' tech and all. They claimed my board was too far gone to repair. When I got it back it was painfully obvious a total hack went at it. I absolutely wish I had simply tried to fix it myself. They ruined it! Nobody is born as a qualfied tech. Everybody must learn somehow. I totally understand why people would like to try to solve these issues without 'qualified' intervention.
Right, also true in France, many people talking a lot and so few with real skills.
Fortunatly I know a quite old HIFI manufacturer, passionnated with his job and when I called him yesterday he knew exactly the amp model I have.
When I came in his store I saw he was reparing many Marantz HIFi reciever, I'm also a fan of these old things
50$ to make an investigation and then it depends from the kind of issue he founds.
Thanks for giving me your advices , I thinck I will have to bring my amp next month when I 'll get paid
Have a nice day guys
Fortunatly I know a quite old HIFI manufacturer, passionnated with his job and when I called him yesterday he knew exactly the amp model I have.
When I came in his store I saw he was reparing many Marantz HIFi reciever, I'm also a fan of these old things
50$ to make an investigation and then it depends from the kind of issue he founds.
Thanks for giving me your advices , I thinck I will have to bring my amp next month when I 'll get paid
Have a nice day guys
Sounds like it could be cold solder joints on the large power resistors on the preamp board. On older (US made) WT amps, these resistors are part of a circuit with zener diodes that drop the supply voltage from around 80V to 15V DC and they get hot, often enough to discolor the PCB and cause the solder joints underneath to fail. This failure is a common issue with these amps and will cause the preamp to cut out, sometimes causing loud pops and the flashing of the front panel LEDs. On my WT-500, I replaced the original 5W resistors with 10W units and cleaned up the solder joints. Others have used heatsinks and/or attached the power resistors to the chassis, away from the PCB. A little searching should bring up some of the solutions.I am investigating on an issue I have on my favorite Amp.
While I am playing the sound decreasses slowly, till I have no volume at all. And then it increases.
Same problem with the DI, so I guess it is a preamp issue.
It is a bit disturbing if I am on stage
During this, the leds of the equalizer are all lightening red.
I thought it was the tube that was KO but after changing it same problem occurs.
Do you have any idea of where does this come from ? Is it a "typical Eden WT" problem ?
is expensive to fix that ?
The power resistors can be seen in post #20.
There’s a chance your problem is related to those power resistors, but the symptoms are worse. So there’s probably more going on. And that would require actual diagnostic skills.
Modding those resistors doesn’t hurt. I’m one of those who posted about it. But I doubt it will solve your problem. Also: I seem to remember the later models used a different way to control the power input at the pre amp? You should wait for @Bassmann1968 to visit, he’s one of the resident Eden experts.
I do think finding a good repairman is worth it for these amps. Besides them being good amps, they are very repairable.
Modding those resistors doesn’t hurt. I’m one of those who posted about it. But I doubt it will solve your problem. Also: I seem to remember the later models used a different way to control the power input at the pre amp? You should wait for @Bassmann1968 to visit, he’s one of the resident Eden experts.
I do think finding a good repairman is worth it for these amps. Besides them being good amps, they are very repairable.
I moved the resistors off the board on my WT400, heres a post with the process if you wanted to share with the repairman you are using.Right, also true in France, many people talking a lot and so few with real skills.
Fortunatly I know a quite old HIFI manufacturer, passionnated with his job and when I called him yesterday he knew exactly the amp model I have.
When I came in his store I saw he was reparing many Marantz HIFi reciever, I'm also a fan of these old things
50$ to make an investigation and then it depends from the kind of issue he founds.
Thanks for giving me your advices , I thinck I will have to bring my amp next month when I 'll get paid
Have a nice day guys
Eden WT400 repair/mod
The WT-X05 series had a different issue (than the WT-X00 series) with the low voltage regulators early in their production (if I remember correctly)
Thanks for this video but my issue is quite different : The volume decreases in a few seconds and then increases with no "click"
Heres are a few pics of my amp's guts.
As you can see the two resistance seem to have been already touched and glued to the board.
Some of of the capacities and tored transformer.
As you can see the two resistance seem to have been already touched and glued to the board.
Some of of the capacities and tored transformer.
