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Feb 12, 2019 22:07:10 GMT -5
Post by Ex_Vintage on Feb 12, 2019 22:07:10 GMT -5
105c caps SHOULD have a longer lifetime and higher reliability. If the amp came with 105c, THAT'S what goes back in. period. If the amp came with 85c, No Harm in going to 105c. 105C caps have a shorter lifetime than a similar 85C part. As was stated, the failure mechanism is vaporization of the electrolyte which is the same for an 85C or a 105C part (they use the same electrolyte). The higher the temperature the part is operated at the greater the vaporization rate and subsequent lifetime reduction. Higher operating temperature is realized by a combination of local ambient temperature and the operating current stress. 105C parts will have a lower rated current than an 85C part given an equal volume.The advantage of the Liquid-type 'lytics is they are self healing. The anode foil will REOXIDE. Only film caps have a "self healing" property. When the insulating layer in a film cap fails, the resultant short clears the metalization off of the film and they "self heal"
resulting in a slight loss of capacitance. When the insulating paper in an electrolytic cap fails, the resultant short causes an arc and the associated heating boils the electrolyte and they expand rapidly (explode or vent) And when a piece of equipemnt has been out of service for an extended time period, it can be saved sometimes by brining up the voltage SLOWLY with a Variac and allowing the caps to heal. Electrolytic caps that have been unused for several years may need to be reformed. Using a variac or a current limited voltage source which will allow the re-formation of oxide on the aluminum foil re-establishing its voltage withstand capability.Nelson Pass is on record as saying that such 'wet' caps SHOULD last 20 years or more. No that it means anything, but I have an old Kenwood Ingtegrated with original caps. This amp is around 30 years old and my nephew uses it for his guitar, of all things. 'Audio Grade'? I don't know. Many DIY guys I know use the Panasonic 'computer grade', whatever the heck THAT means. And YES, by all means. Cooler gear lasts longer with fewer wacky failures. People that stack stuff up and shake their heads when stuff breaks makes me shake MY head.
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Feb 12, 2019 22:12:46 GMT -5
Post by DavidR on Feb 12, 2019 22:12:46 GMT -5
And if you cannot find 105, than 85 is fine. Period. Who knows why Emo used 105 to begin with; they got a good deal on a lot, used them in other earlier equipment and had many leftover, etc.. Russ It's not an Emotiva amp. Its a Sherbourn with a few additions by Emotiva. DYohn stated what the difference is with 105' vs 85'
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Post by teaman on Feb 13, 2019 1:00:09 GMT -5
And if you cannot find 105, than 85 is fine. Period. Who knows why Emo used 105 to begin with; they got a good deal on a lot, used them in other earlier equipment and had many leftover, etc.. Russ It's not an Emotiva amp. Its a Sherbourn with a few additions by Emotiva. DYohn stated what the difference is with 105' vs 85' If it was sold by Emotiva it was an Emotiva amp. These SA-250 Audiophile quality amps were marketed as brand new entries by Dan, with top quality internals that bettered the XPA-2. That sir, is an Emotiva amp.
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Feb 13, 2019 1:13:46 GMT -5
Post by leonski on Feb 13, 2019 1:13:46 GMT -5
And if you cannot find 105, than 85 is fine. Period. Who knows why Emo used 105 to begin with; they got a good deal on a lot, used them in other earlier equipment and had many leftover, etc.. Russ I 00% understand your view vis-a-vis cap temp. that being said, I'd be reluctant to 2nd guess the original specs and go to a LOWER temp rated cap. do the designer / engineers know something we don't? Maybe.....maybe not..... And yes, they might have had a bunch of the 105c rated laying about. Or simply gotten such a good price on 'em it was Too Good to pass up. Unstacked gear in the open? I'l give you 90%++ of getting away with 85c. Stacked or enclosed? Go with 105c.
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Feb 13, 2019 1:34:46 GMT -5
Post by garbulky on Feb 13, 2019 1:34:46 GMT -5
It's not an Emotiva amp. Its a Sherbourn with a few additions by Emotiva. DYohn stated what the difference is with 105' vs 85' If it was sold by Emotiva it was an Emotiva amp. These SA-250 Audiophile quality amps were marketed as brand new entries by Dan, with top quality internals that bettered the XPA-2. That sir, is an Emotiva amp. I guess it's a matter of perspective. Yes it is an Emotiva brand amp. But Emotiva owned Sherbourne and the two companies shared very similar design. I beleive this one was based on the PA-2 250 which was also very similar to the XPA-2. Though of course there were some changes like the neat gain swithc. I would be interested in hearing one of these units. I'm not sure why they are having a tough time with QC on them.
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Feb 13, 2019 1:36:14 GMT -5
Post by teaman on Feb 13, 2019 1:36:14 GMT -5
If it was sold by Emotiva it was an Emotiva amp. These SA-250 Audiophile quality amps were marketed as brand new entries by Dan, with top quality internals that bettered the XPA-2. That sir, is an Emotiva amp. I guess it's a matter of perspective. Yes it is an Emotiva brand amp. But Emotiva owned Sherbourne and the two companies shared very similar design. I beleive this one was based on the PA-2 250 which was also very similar to the XPA-2. Though of course there were some changes like the neat gain swithc. I would be interested in hearing one of these units. I'm not sure why they are having a tough time with QC on them. I'm pretty sure the QC has gone downhill since the assembly came back stateside so I expect less now than I did then.
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Feb 13, 2019 10:26:38 GMT -5
Post by DavidR on Feb 13, 2019 10:26:38 GMT -5
My understanding is that they had a number of these Sherbourn amps lying around and decided to move the stock. DragonV seems to have a very serious issue and very different from chicagorspec. At first I thought the PS caps were leaking from manufacturing defect and not ruptured from venting.
Gar, they've only had issues with a handful of these; maybe 1% Wonderful sounding amp and seems to loaf around with difficult loads.
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Feb 13, 2019 11:10:18 GMT -5
Post by Deleted on Feb 13, 2019 11:10:18 GMT -5
Will these fit? www.amazon.com/Capacitor-Rubycon-10000uf-Electrolytic-degree/dp/B00YAP73B0You can call a distributor that sells what brand/type you want and ask if they have the lug spacing/size you need. All Japanese caps are considered of high quality, and I like the following cap brands: Rubycon United Chemi-Con (or Nippon Chemi-Con) Nichicon Sanyo/Suncon Panasonic Hitachi FPCAP or Functional Polymer Capacitor (ex-Fujitsu caps segment, which was bought by Nichicon) ELNA Besides Japanese manufacturers there are also several US and European vendors that make high-quality capacitors. Probably we won't meet any of the below cap brands inside a consumer grade PSU, at least their electrolytic offerings, but we decided that it still worth mentioning them. Cornell Dubilier (USA) Illinois Capacitor (Currently owned my Cornell Dubilier) Kemet Corporation (USA) Vishay (USA) EPCOS (TDK company, Germany) Würth Elektronik (Germany) Second-Tier Caps On this list you will find capacitors made by some of the Taiwanese manufacturers, which often use factories in China. These caps perform well, so they are usually used in mid-level PSUs and sometimes even in high-end units, and they strike a balance between good performance and affordable prices. Taicon (belongs to Nichicon) Teapo SamXon (except GF series which belongs to a lower Tier) OST Toshin Kogyo Third-Tier Caps These third-tier capacitors, according to information from various PSU manufacturers and people with knowledge of RMA statistics, along with our own experiences with caps, might not be among the best choices, but are still a grade above the caps that belong to the last category. Jamicon CapXon This group includes the rest of the capacitor brands. When you see one of these brands in a contemporary PSU, you’ll know that the manufacturer set lower-cost production as a priority instead of reliability over time. We are listing only the popular cap brands that are usually found in low-cost PSUs, but we are well aware that many other low-cost cap brands exist and there is a good chance that you'll find them in non-branded PSU, and even in some branded units. G-Luxon Su'scon Elite Lelon Ltec Jun Fu Fuhjyyu Evercon
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Feb 14, 2019 14:28:39 GMT -5
Post by leonski on Feb 14, 2019 14:28:39 GMT -5
I don't see the need to go beyond the 'First String' list from texzick. ALL good brands, the only one I'm not familiar with is United Chemi-con, but that doesn't mean much.
I'm partial to the Panasonic in the correct range (they make a bunch of different lines) or ELNA, which I think is in my Parasound.
No Reason to go 'Off The Charts' $$$, since these kinds of parts are essentially commodity.
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Feb 14, 2019 23:25:18 GMT -5
Post by dragonV on Feb 14, 2019 23:25:18 GMT -5
Thanks again for all the replies. I will be very happy to stick with a quality lower priced cap if can locate them. Have sent that many emails and searched a heap of sites. The drama is finding the specific specs in particular the heat rating, and in stock. Plenty of suppliers will be happy to supply me 200 of them minimum order if I can wait 28 weeks!! eBay, Amazon etc have all been fakes and more fakes. I had no idea until this repair that there were so many fake capacitors still being put out...though I do remember the capacitor scandal from many years ago. So basically it is spend a couple hundred on Mundorf or keep searching...if anyone can prove me wrong and find a better option I would be very happy!!! 👍👍🤪
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Feb 15, 2019 9:16:46 GMT -5
Post by DavidR on Feb 15, 2019 9:16:46 GMT -5
The Mundorf don't have the snap in connectors.
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Feb 15, 2019 10:10:29 GMT -5
Post by dragonV on Feb 15, 2019 10:10:29 GMT -5
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Feb 15, 2019 11:13:08 GMT -5
via mobile
Post by audiosyndrome on Feb 15, 2019 11:13:08 GMT -5
Once again, 105 not necessary. 85 will do fine.
Russ
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Feb 15, 2019 12:38:02 GMT -5
Post by DavidR on Feb 15, 2019 12:38:02 GMT -5
Once again, 105 not necessary. 85 will do fine. Russ For performance it is
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Feb 15, 2019 12:40:23 GMT -5
Post by DavidR on Feb 15, 2019 12:40:23 GMT -5
Those don't look like snap-in connectors. This is a snap in connector
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Post by Ex_Vintage on Feb 15, 2019 17:42:51 GMT -5
Once again, 105 not necessary. 85 will do fine. Russ For performance it is Please specify the "performance" parameters of the 105C caps. Thanks
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Feb 15, 2019 18:20:06 GMT -5
Post by DavidR on Feb 15, 2019 18:20:06 GMT -5
Please specify the "performance" parameters of the 105C caps. Thanks read the posts in the thread. someone 'in the know' has it correct.
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Feb 16, 2019 12:55:24 GMT -5
Post by audiosyndrome on Feb 16, 2019 12:55:24 GMT -5
Please specify the "performance" parameters of the 105C caps. Thanks read the posts in the thread. someone 'in the know' has it correct. DavidR- Ex-Vintages' question was rhetorical. He knows the correct answer as do I. There is no "performance" difference between an 85C capacitor and an 105C capacitor in the subject application. That application being a power supply revisor cap in a consumer electronic product. If the ambient temperature plus the internal temperature rise come even close to 85C, then something is very wrong with the design of the product, or it's in an environment that's not meant to be e.g., in a rack in a closet with no forced air ventilation. At best 105C offers a slight increase in margin. 105C makes sense for some military equipment which has to operate full performance to specification at 55C and must be able to survive storage at 70C. But for consumer electronic equipment, nada, no, nicht regardless of what is posted above in this thread. By the way, the OP posted early on that the 105C requirement was the major difficulty in finding a replacement part for the caps and even the Stones know "you can't always get what you want". Russ BSEE, MSEE
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Feb 16, 2019 14:15:13 GMT -5
Post by leonski on Feb 16, 2019 14:15:13 GMT -5
Regardless: Go with what the designer / builder intended. That is 'safe'.
Very, Very unlikely the 85c will fail on that basis, but......If the piece is stacked or used in an enclosure? Or if the PS design is crowded and runs warm, anyway?
I am reliably told that the higher temp caps ALSO have a higher ESR.....which is the 'Sum of Equivelent Series Resistance'.
In some circuits it makes a difference. Others? Not. The extra resistance tends to limit surge current at startup, if THAT'S an issue?
Capacitors and inductors are NOT purely and only capacitance or inductance. They also are 'resistive' and that's where the waters get muddied. How much resistance is acceptable in any given circuit or usage? For example? The inductor in my Magnepans is 040ohms DCR. DC resistance. This part can be easily replaced with a part of 1/2 or less the DCR, but it changes the level of the driver it is connected to. A small change, to be sure but effectively a redesign of the original intent. Some of the speaker mod guys like the change....others not so much. I doubt I'd hear the difference.
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Post by DavidR on Feb 16, 2019 21:43:49 GMT -5
Regardless of whether or not the OP can get 105C or use 85C is NOT his biggest issue. Finding the cause of why the PS cap keep rupturing/venting IS his biggest issue.
David, BSME Northeastern U
You can get the caps in 105C and that's what the designer used and that's what I'd use if I had to replace them.
You can hash out the differences with the other EE.
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