Hi:
Audio newbie here, and little to no understanding of electronics. I can solder. I do know that one of the large eletrolytic caps in my MiniDSP 2x8 is bulging. It's one of a pair, so obviously I might as well replace both.
Can someone tell me what purpose these caps serve and whether they are in the audio path or not? They're 3300uF and the brand name appears to be ChangX. If I'm correct about that, aren't those renowned for being of poor quality/reliability?
Also, what are the black flat-ish rectangular components in the next pics labelled "m-tek d4101dag"? Google searches seem to suggest they're voltage regulators? If so, is there ever any tiny variation on how flat the tops should be? Because two of them seem to almost completely flat on top, but not as flat as the other two. If I'm replacing components, I only want to do it once if something might be flaky. Does anyone know if those rectangular things are through-hole or surface mount? I'm pretty decent at soldering, but couldn't do SMT if my life depended on it.
Thanks
Audio newbie here, and little to no understanding of electronics. I can solder. I do know that one of the large eletrolytic caps in my MiniDSP 2x8 is bulging. It's one of a pair, so obviously I might as well replace both.
Can someone tell me what purpose these caps serve and whether they are in the audio path or not? They're 3300uF and the brand name appears to be ChangX. If I'm correct about that, aren't those renowned for being of poor quality/reliability?
Also, what are the black flat-ish rectangular components in the next pics labelled "m-tek d4101dag"? Google searches seem to suggest they're voltage regulators? If so, is there ever any tiny variation on how flat the tops should be? Because two of them seem to almost completely flat on top, but not as flat as the other two. If I'm replacing components, I only want to do it once if something might be flaky. Does anyone know if those rectangular things are through-hole or surface mount? I'm pretty decent at soldering, but couldn't do SMT if my life depended on it.
Thanks
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I'd put money on that those are common mode chokes, for the audio I/O. Prevent ultrasonic frequencies (RF...) from getting into the audio path. No need to touch.
Okay, great. What are some brands/models of really long-lasting caps I could use to replace those power supply caps?
And while I'm asking about that, do capacitors sometimes bulge because the gear hasn't been used, or is it always a sign of poor quality?
I was thinking of replacing those rectangular components, not to improve audio quality, but because it seems like two out of four have a very tiny arch/bowing at the top, whereas the other two are flat. It's barely noticeable, but it's there. Chokes wouldn't ever bulge, right? Or could the be embeded in some chemical that might?
And while I'm asking about that, do capacitors sometimes bulge because the gear hasn't been used, or is it always a sign of poor quality?
I was thinking of replacing those rectangular components, not to improve audio quality, but because it seems like two out of four have a very tiny arch/bowing at the top, whereas the other two are flat. It's barely noticeable, but it's there. Chokes wouldn't ever bulge, right? Or could the be embeded in some chemical that might?
It could be a simple as a little bit more encapsulating stuff got put over the coils on the one that appears domed. Nothin' I'd worry about.
How about https://www.ebay.com/itm/144669797737 for replacement caps - if they'll fit. (For <$10 shipped, I'd make them fit...)
How about https://www.ebay.com/itm/144669797737 for replacement caps - if they'll fit. (For <$10 shipped, I'd make them fit...)
Are we all sure that's a good place to add extra capacitance? Also, how do I know what physical size is appropriate to fit in there?
Do I just measure the distance between the leads?
Do I just measure the distance between the leads?
REPLACE the caps!
How will you add capacitance unless you change the value during replacement?
Any Japanese brand, Vishay, TDK Epcos, Sprague....all are good.
If needed, go for a higher voltage rating. Even 63V are good enough.
And order the smaller value ones as well if needed, might as well change all the electrolytics together.
Buy them from any reputed supplier, check the landed at your door cost, shipping charges vary a lot.
Sizes are pretty standard, check the existing ones with a ruler or tape.
Can put bigger ones if there is room in the housing.
3300uF is a common rating, don't worry about finding them.
How will you add capacitance unless you change the value during replacement?
Any Japanese brand, Vishay, TDK Epcos, Sprague....all are good.
If needed, go for a higher voltage rating. Even 63V are good enough.
And order the smaller value ones as well if needed, might as well change all the electrolytics together.
Buy them from any reputed supplier, check the landed at your door cost, shipping charges vary a lot.
Sizes are pretty standard, check the existing ones with a ruler or tape.
Can put bigger ones if there is room in the housing.
3300uF is a common rating, don't worry about finding them.
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SPDIF transformers most likely. The bulge is the encapsulation resin doing its thing after it's been squirted into the mold. They're fine.
Make sure to measure the pin spacing of your caps before you order replacements. They're probably 5mm, but it would be a bummer if they're 6.35mm and you get the wrong ones. Likewise for diameter and height. You can buy thicker/taller ones if they fit, but the pin spacing is not really negotiable. If you're in EU, try Reichelt.
About ebay caps...
At least Rubycon, not a chop-suey brand!
If genuine Rubycon, of course.
Which is why I tend to use Keltron, cheap and good quality.
If genuine Rubycon, of course.
Which is why I tend to use Keltron, cheap and good quality.
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Yeah, I've read not to buy from eBay sellers before. Some real horror stories sometimes.
I'll go with the Rubycons.
I'll go with the Rubycons.
Yeah. I guess you have to do your homework; at least as much thought as on size, value, voltage etc. This would be in the context of who's selling. In the case of the ebay part I suggested, I note seller is 99.9% positive, which is ebay's means of reflecting a satisfied customer - and that's across 11k+ sales. I'd say chances are the part you'd receive would be that depicted in the listing; an actual Nichicon Gold audio grade cap.
Now for what sonic value having a Nichicon Gold audio grade cap in that particular position, I dunno. I assume Nichicon at least tried to make a good product.
It is a filter in the power supply, so an audiophile grade capacitor is a waste.
Better go for a type more suited for SMPS.
Or whichever is cheap and good...
Better go for a type more suited for SMPS.
Or whichever is cheap and good...
I've never understood why people buy electronic components on ePay - unless they're out of production and not available elsewhere. Even with shipping it's usually cheaper to order from Digikey.
As for the original question: De-solder the caps. Measure the pin pitch and diameter. Pick a cap by a good manufacturer (CDE, Rubicon, Nichicon, Panasonic, etc.) Get the same capacitance and the same or higher voltage rating. The pin pitch is critical. And don't exceed the diameter of the OEM cap (smaller is fine).
Tom
As for the original question: De-solder the caps. Measure the pin pitch and diameter. Pick a cap by a good manufacturer (CDE, Rubicon, Nichicon, Panasonic, etc.) Get the same capacitance and the same or higher voltage rating. The pin pitch is critical. And don't exceed the diameter of the OEM cap (smaller is fine).
Tom
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwj-s5HIoLb5AhWpqVYBHdpCAmcQFnoECBoQAQ&url=https://www.electrikkart.com/keltron-3300uf-50v-85-18x37mm-50pcs&usg=AOvVaw2Z7HJauLyXi1QDfdrUhtUy
About 40 cents each, Keltron 3300uF/35V.
I have no ties to seller.
Buy regular caps, the cheapest from a reputed maker, from a reputed seller.
Pitch can be got around by bending leads, if the one you need is not in stock or wildly expensive in comparison.
And if you have room, as in this case, a larger cap, slightly higher off the board, is fine as well.
That said, it is not an odd value, should be in stock at most places.
About 40 cents each, Keltron 3300uF/35V.
I have no ties to seller.
Buy regular caps, the cheapest from a reputed maker, from a reputed seller.
Pitch can be got around by bending leads, if the one you need is not in stock or wildly expensive in comparison.
And if you have room, as in this case, a larger cap, slightly higher off the board, is fine as well.
That said, it is not an odd value, should be in stock at most places.
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Thanks everybody. That's great advice. I will follow up on it as soon as I can.
Now, if I could just figure out how to get the darn thing to take a firmware update. The unit keeps disconnecting from my PC, and the solution is a firmware update. Wow, bad problem cause obviously if I can't keep a stable connecting to it, how can I update the firmware?
Now, if I could just figure out how to get the darn thing to take a firmware update. The unit keeps disconnecting from my PC, and the solution is a firmware update. Wow, bad problem cause obviously if I can't keep a stable connecting to it, how can I update the firmware?
Those black plastic things are the SPDIF isolation transformers.
If I were you I would buy the caps from RS Components as you know what you're getting.
I assume you haven't replaced the caps yet and the're in the onboard SMPS so the problem with not a updating could be due to unstable voltage rails. Replace the caps then try again.
If I were you I would buy the caps from RS Components as you know what you're getting.
I assume you haven't replaced the caps yet and the're in the onboard SMPS so the problem with not a updating could be due to unstable voltage rails. Replace the caps then try again.