1 (edited by ning 2020-12-10 17:06:11)

Topic: capacitor leakage?

I found one of the capacitor in my 4-month-old ADI-2 PRO FS R BE looks weird. Not sure if it's leaking or not ---I had only seen one leaking from the top with a lot of burning traces, not from the side like this one (picture attached).  Is this normal and is there some way to test without voiding the warranty? It's the ones near the front, close to DAC ships.

https://i.ibb.co/sy6pLpq/capacitor.png

Re: capacitor leakage?

It won't leak, for now - it doesn't look like there's a hole, just a dent...
Looks like someone pricked it with a pointy screwdriver - shouldn't be deadly for some time.
I'd rather swap for any 2200mf common panasonic one, or similar, for now.
PRO FS is well known for overheating - try to keep it cool if replacing a cap is not an option now.

3 (edited by KaiS 2020-12-11 07:32:47)

Re: capacitor leakage?

This cap should be replaced under warrenty - not by you.

ADI-2 Pro is not "well known for overheating", but it gets significantly warm - depending on airflow and output power it has to deliver.

The hottest I could measure, at continous full power, on the headphone amplifier chips, was about 75°C.
Idle it's about 35°C.
A PC CPU runs up to 95-105°C before it throttles.

Best not to stuff ADI-2 inbetween other devices.

4 (edited by ning 2020-12-11 00:39:18)

Re: capacitor leakage?

KaiS wrote:

This cap should be replaced under warrenty - not by you.

I agree. But the replacement is not as simple as visiting my nearby apple store next street (there are five in the city I currently live). A lot of factors, including coronavirus, holiday break, customs, dealer's relays, for instance, that resulted my ADI-2 took 4 months and 100Euro+ shipping/tax this year to repair for free under warranty. I thank RME (especially MC) wholeheartedly for doing the best they could possibly do --- They really did a fantastic job and I fully appreciate it. But I still wish things could be easier.

So if this cap is broken I would either go through your suggested route as I just did this year, or bite the bullet to fix it myself under $1 at the cost of voiding the warranty. If it's just cosmetics and not a problem as yuriy_yarosh said, I would just table it.

Re: capacitor leakage?

I thought to see a dent in the cap.
That's a killer, as it affects it's reliability.

If you can DIY depends on you skills, but voiding the warrenty you might loose more then you gain.

There are 20 more month left where things could break you cannot fix DIY.

I suggest to try working out a "no cost on your side" solution with your dealer, as he's fully reponsible for the warrenty within the first 6 month.
It's not correct letting you pay shipping and customs/tax.
EU regulations are clear on that point.


If that doesn't work, contact RME to inform them about the dealer's behavior - MC and other RME people are reading along here anyway, but ...

6 (edited by ning 2020-12-11 00:33:54)

Re: capacitor leakage?

Thanks for the advice.

Actually this brand new device is a replacement of a 10-month-old previous broken device. There's only 6 months  warranty left (= 24-10[previous device life span]-4[time to fix it] - 4 [current device age]). I assume the dealer is law-abiding for letting me pay the shipping as it's beyond first 6 months. I also messed up the import tax myself as I just immigrated to a new country whose tax code I'm not familiar with, and I had my lesson learned :-(

7 (edited by KaiS 2020-12-11 01:28:15)

Re: capacitor leakage?

How's your solder skills and equipment?

Is the cap really dented?
Or just a blop of solder glued to it?

8 (edited by ning 2020-12-11 02:00:29)

Re: capacitor leakage?

KaiS wrote:

How's your solder skills and equipment?

Is the cap really dented?
Or just a blop of solder glued to it?

good enough for through hole.

Can't see clearly --- I haven't removed the warranty sticker on the bottom yet, and can only peek on the front side --- I can leave the sticker intact by removing the front panel only (don't tell MC I did that. smile ).

9

Re: capacitor leakage?

For the record: warranty is already voided by opening the unit. Replacing this through hole cap is nearly impossible without special tools. They have one pin on ground in a 10 layer (!) PCB. While I can't explain the scratch it doesn't look critical to me. This cap only has stable, no ripple and near zero current 5 V DC on it, it will never break or dry out as it is not stressed at all. I would just let it be as it is.

Also for me it looks like a soldering iron hit the cap, just melting away the plastic sleeve, and may have a little solder drop left. This is not a damaged cap, IMHO. The outer metal hull is quite strong and can't be damaged by this or a 'screw driver'.

Regards
Matthias Carstens
RME

10 (edited by ning 2020-12-11 16:50:51)

Re: capacitor leakage?

MC wrote:

For the record: warranty is already voided by opening the unit.

Manual only mentioned "warranty is void if seals have been damaged" but didn't strictly imply that's also true when customer opens the unit. In addition the warranty seal can easily be legally challenged. [Disclaimer: This is not a legal advice] In the US, warranty sticker is usually considered not valid at all. EU law may also lean strongly on customer's side if no change is being made to the device.

I understand promoting publicly "freedom to repair" may cause a lot of trouble for manufacturers.
But I hope manufacturers could be more tolerant, especially to actions that do not cause harms.
My wife's childhood curiosity of tearing down her Christmas gifts, for instance, stimulated her to pursue STEM education, and become a successful engineer. We certainly need more people who can create amazing engineering wonders like the ADI-2s.

MC wrote:

Also for me it looks like a soldering iron hit the cap, just melting away the plastic sleeve, and may have a little solder drop left. This is not a damaged cap, IMHO. The outer metal hull is quite strong and can't be damaged by this or a 'screw driver'.

Thanks for your input, MC! Your professional feedback solves my concern! I can now have a sound sleep in the evening wink

11 (edited by RME_fan 2023-01-20 11:24:17)

Re: capacitor leakage?

MC wrote:

For the record: warranty is already voided by opening the unit. Replacing this through hole cap is nearly impossible without special tools. They have one pin on ground in a 10 layer (!) PCB. While I can't explain the scratch it doesn't look critical to me. This cap only has stable, no ripple and near zero current 5 V DC on it, it will never break or dry out as it is not stressed at all. I would just let it be as it is.

What will happen later on 20-30 years from now or more? Can the capacitors be replaced with a soldering iron then? The capacitance or ESR of electrolytic capacitors can deteriorate by then.

12 (edited by KaiS 2022-04-18 20:46:51)

Re: capacitor leakage?

RME_fan wrote:
MC wrote:

Replacing this through hole cap is nearly impossible without special tools. They have one pin on ground in a 10 layer (!) PCB. ...

What will happen later on 20-30 years from now or more? Can the capacitors be replaced with a soldering iron then? ...

It can be replaced, I already did that.
It‘s just not an average Joe’s DIY job.

You need some special tools.
Call me in 30 years then smile

13 (edited by RME_fan 2022-04-18 23:38:01)

Re: capacitor leakage?

KaiS wrote:

It can be replaced, I already did that.
It‘s just not an average Joe’s DIY job.

You need some special tools.
Call me in 30 years then smile

Can I get an explanation of the special tools needed to replace the capacitors and the specific technique needed if there is any, or is this a trade secret? smile

Re: capacitor leakage?

There're tools which can do it very quickly and reliable --- for instance a desoldering iron that has a vacuum sucker pump.
But for caps you don't really need those tools.
Just use two soldering iron and melt both joints at the same time, then you can pull it off from the front side easily.

As said by MC and KaiS, I wouldn't worry about the caps at all. other electronic parts surely have shorter life span than the caps, and are way more complex to replace.

15

Re: capacitor leakage?

ning, you missed the 10 layer PCB. Several of these are planes. Trying your trick will damage either the vias (all through-hole pads here are vias) or not work at all. One needs a lot of heating power, often enough putting the whole PCB on a heater, to get things off and out.

Regards
Matthias Carstens
RME

16 (edited by Johannes AU 2022-04-19 06:28:01)

Re: capacitor leakage?

RME_fan wrote:
KaiS wrote:

It can be replaced, I already did that.
It‘s just not an average Joe’s DIY job.

You need some special tools.
Call me in 30 years then smile

Can I get an explanation of the special tools needed to replace the capacitors and the specific technique needed if there is any, or is this a trade secret? smile

It is not a secret, SMT is known for years, it needs special equipment during manufacturing, not as simple as soldering a pass through componet like resistor or capacitor which is easier using a good soldering iron with temperature control and a suction pump. A skillful electrician possibly can handles it with extreme care, some cannot due to the complexicity and miniature size of the circuit and componemts.

A capacitor can be replace with its own old legs remain at the circuit board and solder the new one to its old legs, but not easy to do it. Temperature control is important otherwise will damage the board and other electronic componets.

Pacifist, dumb, not stupid
Listen music out from a box which sounds
Reading words on paper/ screen

17 (edited by KaiS 2022-04-19 13:03:20)

Re: capacitor leakage?

RME_fan wrote:
KaiS wrote:

It can be replaced, I already did that.
It‘s just not an average Joe’s DIY job.

You need some special tools.
Call me in 30 years then smile

Can I get an explanation of the special tools needed to replace the capacitors and the specific technique needed if there is any, or is this a trade secret? smile

It needs the tools and material, a lot of experience and careful handling.

As mentioned by MC, the solder pads are through-hole contacts with connections to board-internal layers.
Combine heat (you need a lot) AND pull and you can almost be sure to send the board into the happy hunting grounds, by ripping and pulling out the contacting tubes.


There‘s no reason to remove the caps anyway. All functional testing can be done in-board.
I only did it to gain the workspace to replace an OPA1688, even less of an easy job.


There are NO caps in the signal path in ADI-2 DAC, and only 2 pairs in a special arrangement in the analog inputs in ADI-2 Pro.

Nothing to gain by fooling around with the caps, like the guy who replaced them all by too small valued foil caps with too long connect wires.
(I‘m bet ADI-2 sounded different after this stupid action, because it didn‘t work properly any more).


If you really NEED the info how to do it, send a PM, but I will not inspire the fools to fool around by making it public here.