Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: cotton on March 18, 2009, 10:52:05 am
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Are you guys having good luck with these? I repeatedly read about high rate of failure with this brand e-caps. Anybody have a long term relationship with Illinois?
Thank You
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Good quality industrial caps. No problems when properly used. Quite inexpensive.
Maybe they'd be more popular if shipped in an oversized can at four times their price...
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Doug sells a lot of them here and I haven't heard anything suggesting they're not reliable. Maybe you heard from someone who stumbled on a bum lot? It happens once in a while with anything factory made and mass marketed, but I haven't even heard anything like that at all about the Illinois caps. Where have you been reading it?
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Doug sells a lot of them here and I haven't heard anything suggesting they're not reliable. Maybe you heard from someone who stumbled on a bum lot? It happens once in a while with anything factory made and mass marketed, but I haven't even heard anything like that at all about the Illinois caps. Where have you been reading it?
Oh Man -
On every forum I have ever been on. Seymour Duncan, The Gear Page, Dr.Z, etc. Here is just the latest...
http://www.fenderforum.com/forum.html?db=&topic_number=705251&lastpost=2009-03-1806:05:43
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Much of the anti-Illinois cap noise comes from Gerald Weber, lots of people have his books...and spread his "sales spiel" as facts.
I've re-capped so many amps with Illinois that I can't even estimate the number, I've never had a bum one...or one come back for a recap in the nearly 15 years that I've done this.
j.
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I have nothing against Illinois or their Caps. I've used them myself. But, I had a Blues Junior in the shop the other day that was only a few years old and all the Illinois caps had failed with stuff was coming out of the end. I replaced them all. The amp was not abused.
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I have nothing against Illinois or their Caps. I've used them myself. But, I had a Blues Junior in the shop the other day that was only a few years old and all the Illinois caps had failed with stuff was coming out of the end. I replaced them all. The amp was not abused.
Stories like this is what made me ask. This is not an isolated failure. I have been hearing stuff like this about IC for the last several years. So when I saw that they are sold on The Hoffman website, I thought I would see what kind of long term relationship you guys have had with IC.
I do not want to damage anybody's reputation, don't have an axe to grind with IC, and do not have much experience with IC. I have always used Ruby, Sprauge, Xicon, or F&T e-caps. Illinois is the only caps I have heard continuous complaints about. I just installed some IC 22/500 filter caps in an old Magnatone, but I am wondering if I should pull them out......
Thanks
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Pretty odd about the BJ, mines 5 + years old, looks pretty good I take care of it no tears, but its been riden hard at rehearsal's and small gigs and I'll tell ya the biggest bug a boo about them is the darn tube sockets on that board like to unsolder themselves. I wet a iron with just a small amount of solder and hit each one and it goes to working again. Cap's havn't been an issue at all, so it could a isolated incident. I've got some real small Illinois Caps in my little green juke 5e3 and then been doing great. I like anything but Spragues which I try to boycott if possible just because of price more than anything else.
Regards,
Dyna
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Both these stories are about bad stock caps on Blues Juniors... maybe there is something in the assembly process that is killing them early. I've used 'em in a handful of amps over the last 2 years and haven't had anything back or heard anything negative from the owners.
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Plenty of amps come through my shop with Illinois caps. Tube and solid state. Never seen a failure yet.
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Posting on an old thread here ...
I just picked up Gerald's latest book (2009 printing) and was surprised at how vehemently he speaks against Illinois caps; however, I've a friend who's an amp tech and swears he prefers the Illinois over Sprague Atom's. He's had problems with the Atom's in the past and never with the Illinois'.
Nice to see some support for them here. I've got 'em in my 5F2 and 5E3 and I think they sound great.
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I've used more Illinois than Atoms. Never had one fail. They're smaller and cheaper. I've been a tech all my life but this is just a hobby. Most of the people here have a more meaningful opinion than mine.
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Some of the guys over at the power scaling site don't like IC caps. Some of the same guys don't like sprague and F&T either. KOC and some others there seem to favor the small radial types like nichicon VZ(M) series iirc.
I've seen/read where Gerald wrote that he only likes American and some German made types, sprague, F&T and Tech Cap. Also he's said that given say a 20uf/500v. cap, the bigger the physical size of the cap (with same ratings) will always sound/work better, that the larger caps can handle more ripple current. He's also said something about that the newer/smaller type (computer) caps when their made, their "plates" are "etched" during construction to get a larger surface area, to get a higher uf rating in a smaller package, but they can't handle a tube amps current demands.
KOC likes to point to the larger caps like, sprague and F&T, as still using/being made with the old technology of the 50s/60s. That the newer, smaller caps are made with newer/better technology, as a result of being driven by the PC "boom" market, including what their made of, giving a much better cap in a smaller package, lower ESR, higher ripple current ratings, in high temp packages, all at a much lower price to boot.
This is the kind of stuff that drives me crazy about tube amp electronics! :BangHead:
Me, I couldn't tell ya whats what! :laugh:
PRR, what do you think about this ? Would be helpfull to all of us.
Thanks, Brad :smiley:
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OK now I have seen some failures of the 22uF caps in two Blues Juniors. Must have been a bad run of caps.
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Some of the guys over at the power scaling site don't like IC caps. Some of the same guys don't like sprague and F&T either. KOC and some others there seem to favor the small radial types like nichicon VZ(M) series iirc.
I've seen/read where Gerald wrote that he only likes American and some German made types, sprague, F&T and Tech Cap. Also he's said that given say a 20uf/500v. cap, the bigger the physical size of the cap (with same ratings) will always sound/work better, that the larger caps can handle more ripple current. He's also said something about that the newer/smaller type (computer) caps when their made, their "plates" are "etched" during construction to get a larger surface area, to get a higher uf rating in a smaller package, but they can't handle a tube amps current demands.
KOC likes to point to the larger caps like, sprague and F&T, as still using/being made with the old technology of the 50s/60s. That the newer, smaller caps are made with newer/better technology, as a result of being driven by the PC "boom" market, including what their made of, giving a much better cap in a smaller package, lower ESR, higher ripple current ratings, in high temp packages, all at a much lower price to boot.
Crack open a Sprague Atom.... Unless it is over 20+ years old you will see a small modern cap inside that big can. You are paying for an Illinois/Nichicon/Xicon/Sino style stuffed in an oversized/overstuffed can. I've used all types, ATOMs, Nichicon, Xicon, Panasonic, etc. and have never received noticed a difference, nor has anyone else. I only use Spragues anymore on special request.... and haven't had a special request for them in over 3 years.
j.
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Thanks bigsbybender. Thats interesting, dont think thats "fair", but I can belive it.
Brad :smiley:
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Crack open a Sprague Atom.... Unless it is over 20+ years old you will see a small modern cap inside that big can. You are paying for an Illinois/Nichicon/Xicon/Sino style stuffed in an oversized/overstuffed can. I've used all types, ATOMs, Nichicon, Xicon, Panasonic, etc. and have never received noticed a difference, nor has anyone else. I only use Spragues anymore on special request.... and haven't had a special request for them in over 3 years.
j.
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Holy Cow! If anybody wants to post a picture of that I'd love to see it! Thanks for the mythbusting!
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^There it is... in a discussion about this topic a few years back, the only logic anyone could think of behind stuffing a little cap in a big can was for replacement part contracts...(Probably industrial or Military where technology is maintained and may be used for decades.) These would specify for a cap of not only a certain value but specific sizes as well. If you look at large electrical supplier catalogs, it lists the ATOM as a "Replacement Part" specifically.
In the end, Gerald Weber needs "sales points" to sell his amps at enough of a profit to keep him in business. I own all of his books but needed to look beyond what was salesmanship and what is real. He's trying to dig at Fender et. al. for using Illinois caps. Oddly enough he'll claim that you need the ATOM for the "classic" Fender tone, but "Classic" Fenders didn't use ATOMs at all.
j.
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Thanks Sluckey and Bigsbybender. Good to have a little perspective. There's often a lot of BS to wade through in the world of 'mojo' eh?
Cheers.
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why is this post in the tools board?
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Does anyone think he's got a totally objective viewpoint or a subjective interest in this?
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I used them in a lot of my builds in the past, maybe almost all of them. Never had a problem. I did get a bad F&T, one. But never had an issue with the Illinois. Good caps and a good price.
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I have used a ton of Illinos caps in a lot of different applications and had very few failures
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I probably repaired 300 Fenders and other types of amps
I used 22/500v and 100/350v Illinois all day long.
Never got a customer complaint.
Naver saw one fail.
The amps sounded great!
They are also in all the Hoffman 30 watt heads.
I never used Atoms in the repair business or in my amps.
I did use Cornell Dublier 60/500's in the Hoffman 50 and 100 watt heads
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I'm just an avid hobbyist, but I've used the IC's in several builds with no issues. One BIG selling point for me is the smaller size. Makes them fit in some builds better than the Atoms, and leaves a bit more room to work. I don't mind paying less, either. :laugh:
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Have never had a problem with the Illinois capacitors. They are half the price as well as the Spragues
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There seems to be a common thread here, IC caps that are in Fenders seem to have the high failure rate, not the ones we buy on the open market!
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It's dectective work 101. If all the failures seem to come from one amp company (Fender) and most of them from one model (Blues Junior), it would be considered admissable evidence that Fender got a bad run of caps. I've never had a bad Illinois cap and I've used a lot of them. On the other hand, my son's first amp was one of the earliest Blues Junior's. I bought it for him new and it still is just fine... and doesn't sound bad either, BTW. I'd bet the amps with bad caps were all made about the same time. If so, I'd consider that proof!
Dave
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I agree B-bear but I was also wondering about other related issues too. Such as those cheap ass pcb's that are used on them. I've had to re-solder a bunch of contacts on those and who knows what's happening (shorting/overloading) as a result of which one's of those that are going bad and when?
I can say the Illinois caps haven't given me any issues in the past either on any re-cappped or personal build amps, including green board or a tan board BJs that I've modded.
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I do Fender warranty repairs and I have run across a few Fender amps that have had faulty IC caps in them.They start leaking goo out of the positive end and sometimes there is a little bit of hum associated with the amp.
I would say after three years I've done about 4 amps.The preamp 22uf/500v ones were the ones that were leaky.I replace them all because of the PC board removal necessary.
I also have used them in a few amps builds with no issues nyself,but the ones in fenders make me wonder if there was a bad run of the 22uf ones??
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Could there manufacturing process be such that they are over heating them in such a way as to cause premature failure, I only ask because it seems to be all fenders and nothing else.
Thanks Bill
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I think it was a just bad bulk run that Fender purchased from IC.
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I think at this point we all know the story. Fender got a bunch of bad IC caps.....victim of a bad run. It is doubtful if many or ANY of those caps went to Mouser, CE, Hoffman or anybody else. Just one of those Bad Deals that can sink a company's reputation (both Fender and IC). Kind of like what happened with Bridgestone Tires and the Ford Explorer. Both companies make fine tires and fine cars. These things sometimes happen during the manufacture of a product that uses a large number of components.
Also at the time there was that weird Electrolytic Formula Ripp-Off. There was a crucial mis-step in the make up of the paste that effected a large number of caps. I do not know if IC got caught up in that disaster as well.
When I posted this question originally, I was not aware of all the peripheral problems. I have also used quite a few IC caps and as of yet, I have not had a problem with any of them. I was not slighting IC in any way. I was just curious about "all the problems" I had read about IC caps. As it turns out, as normally happens, truth was a bit different than a lot of the stories I read. It was a problem peculiar to Fender, and primarily with one value of cap from IC. That storm is well behind us. Thanks for all the responses, and thanks once again to Doug Hoffman for giving us a medium to talk about "All This Stuff".... :smiley:
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So, maybe, just maybe, Gerald Weber's continual trashing of Illinois Caps is not true? :icon_biggrin:
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In my opinion, Gerald Weber's books are the very best out there as learning tools. I also believe he's like everyone else. He has opinions and beliefs and some of them are pure voodoo. Also, as we all know, what works for one, doesn't always work for another. Take people's facts and make up your own opinions and you can't go too wrong.
Dave
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I'm glad I read this thread. I wondered why I'd shy away from Illinois in my shopping cart... I have two of Weber's books. I'm sure that's why because usually I buy on a budget. I've recently been browsing back through his books after learning and building more... why is there not one plate characteristics chart? Don't get me wrong, I learned quite a bit from the books, but the Illinois lesson will be one I forget.
CHAD
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Quote:" Bridgestone Tires and the Ford Explorer."
Actually I believe it was FIRESTONE tires.Correct me if I'm wrong.
It does put a strain on manufacturers credibility when there are issues with even one product.
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In one of his books, KOC makes mention of "cheap offshore caps" and specifically mentions that IC should be avoided. On this he is in agreement with GW. He is generally a frugal type of builder--this part worries me because he feels it important to pay extra for premium. Aside from the reliability issue, I have replaced IC caps that are working--I can't hear any particular difference in tone. Jim
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Quote:" Bridgestone Tires and the Ford Explorer."
Actually I believe it was FIRESTONE tires.Correct me if I'm wrong.
It does put a strain on manufacturers credibility when there are issues with even one product.
The same company.....
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"In 1988, the (Firestone) company was sold to the Japanese Bridgestone Corporation.
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But for the record,the tires in question were branded 'Firestone' .and I believe owning a company doesn't mean that the manufacturing process of those particular tires had anything to do with Bridgestone proper.
It's really gray area because the design and country of origin,materials used and quality control protocols all come into play when you manufacture large quantities of anything,especially capacitors.We don't know if IC contracts work out to other companies and re-brands them or uses multiple companies to meet quotas etc,etc....
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I vote yes for Illinois! Good results over a period of time, smaller size for easier fitting and smaller price in a continuing inflated economy. What more for you want! :icon_biggrin:
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When thousands of people buy millions of caps, there's bound to be some bad ones. I don't think Spragues are any better... or even as good, just cheap junk living on their name. We're living in a world of corporate junk. The boutique caps are sold in far less quantities. I suspect that their average rate of failure is no better than IC. Remember, if 0.1% of 10,000 is bad, it's only 10 caps. If 0.1% of 10,000,000 is bad, it's 10,000! Which do you think it's more likely you'd hear about?
Dave
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I vote for any 20uf - 450v cap that costs under a buck!
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Makes you wonder if business is down for Sprague electrolytics
There caps just cost quite a bit more than the other choices
Thankgod we have other choices or we would be broke
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In one of his books, KOC makes mention of "cheap offshore caps" and specifically mentions that IC should be avoided. On this he is in agreement with AW. He is generally a frugal type of builder--this part worries me because he feels it important to pay extra for premium. Jim
Hi Jim,
The gist of KOC writings and personal communication is as follows:
KOC dealt with repeated issues of failures with Illinois caps and in his experience IC caps are unreliable. The IC caps has been mentioned in his books. His opinion was a cheap cap that failed, you get what you pay for. "Illinois Caps still make the worst electrolytics on the planet. Their claim to fame was low cost back in the early '80s - their plastics are fine; don't waste your money on their electrolytics!" & "The IC electrolytics are just poorly designed as far as I can tell. Tophat used them and anyone who replaced the caps with any other brand found the amps had better low end response and a less gritty sound.
Illinois Capacitors hit a price point that makes them very appealing - at least it did so ten years ago. The 500V rating on their axial-lead units is also appealing with the prevalence of 470-500V operation of most modern circuits. I was never a fan of axial-lead caps, so had no problem subbing radial-lead units where axials used to be, but many techs are afraid to make such changes.
Modern manufacturing allows less expensive caps than IC's to outperform them very easily. Electrolytic caps are very compromised by design, that is, they deviate from ideal capacitor function in many ways, but Illinois manages to have about the most deviant examples possible."
The owner of Island Amps (another professional Canadian Guitar Amp manufacturer) also saw more than his fair of Fender amps and Peavey with bad IC caps in repair work. "I completely agree with Kevin when it comes to the Illinois caps! I've seen a lot of Peaveys and newer Fenders... so I see a lot of bad Illinois caps." Dante likewise, saw issues with F&T caps. His recommendation, once you go radial, you never go back.
Dante Carrers' comment seems to indicate that IC failures weren't restricted to one model by one manufacturer.
On the repairs that I have done on Fender amps (the non-vintage ones) the components sourced came from the cheapest suppliers, as far as I could determine mostly from China, Thaliand, Indonesia, etc. I couldn't find anything that could be verified as being made in the US, other than the Speakers. Also, the PCB traces were thinner than should have be for long term reliable operation. It was as though every possible cost reduction that could be incorporated into a design was there. I haven't had to replace an IC in a Fender amp, but I've seen and replaced my share of resistors and zeners that should have used a higher wattage for added reliability rather than save a fraction of a penny. It was though overbuilt or overspec'd and Fender are mutually exclusive concepts. Consumer grade quality sold as professional grade product.
KOC does not recommend Atoms caps, any expensive components, or Voodoo parts. His only positive comment on Atoms were their larger physical size reduced parasitic capacitance in some amps, but larger spacing (with smaller sized parts) achieve the same goal for less money.
KOC uses Solen PP film Fast Caps in place of Electrolytic Caps for a clearer sound, reliability, and longer life expectancy than Electrolytic Caps (the life expectancy of the amp). Solens do not have the "electrolytic distortion" that E-caps have (but one can recapture this tonal quality by various methods). To offer a lower price amp model, KOC has introduced an amp with Electrolytic caps.
In his "Super Stock" or updated versions of classic amps or in projects of his design in the TUT series, KOC recommends radial caps for better physical reliability over axial E-caps. And yes, the Axial Caps by any of the "cons" and other brands without "con" in their brand name have been lower priced (Japan's recent disaster may or may not change these prices) and are generally of high quality. This market has been driven by computers, mostly the monitor market. "Mitsushita through their Panasonic brand make very excellent caps at low cost, sold also as Nichicon. These function and sound better than caps costing many times what these do, and occupying much more space than these. Sprague and Mallory are not better than Nichicon but cost a lot more and have the "favoured voodoo" approval."
I have used Atoms (I test all my caps with a Heathkit or Sprague Capacitor tester at full voltage before hand) and Nichicon for that matter, and hadn't had issues others have mention, just as many have used IC without a hitch, especially the history of IC with Hoffman Amps. Your mileage may vary.
Best Regards,
Steve
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Are you guys having good luck with these? I repeatedly read about high rate of failure with this brand e-caps. Anybody have a long term relationship with Illinois?
Thank You
I've heard some people have run into problems with cheap Chinese counterfeit Illinois caps. Apparently the fake versions are much poorer quality than the real thing and will often burst after very little use. If you buy from a reputable supplier you shouldn't run into these. These days with all the Chinese fakes around, if the price seems too good to be true, it just might be.
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Makes you wonder if business is down for Sprague electrolytics
There caps just cost quite a bit more than the other choices
Thankgod we have other choices or we would be broke
Wholesale Distributors that stock Atoms such as CEDist (and also their retail antique electronics supply) run out all of caps from time to time. Sprague Atoms. If people didn't purchase the caps Vishay-Sprague wouldn't continue to manufacture them.
Best Regards,
Steve
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Actually I have a had fair luck with Atom's too :laugh:
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To be perfectly honest, I've never had ANY new cap be bad or go bad on me. I did fix an 18 watt for friend of mine who couldn't make it work and it turned out to be a new Sprague Orange Drop that was defective. That's the only bad cap I've seen except for old ones. Given that, it doesn't make sense for me to pay a premium unless a customer insists. Then it's on HIS dime!
Dave
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So, maybe, just maybe, Gerald Weber's continual trashing of Illinois Caps is not true?
No, that can't be? :l2:
I don't know K O'c dude
Who knows what his beef is, I can only go on my real world results.
Maybe Fender had a batch made for themselves that is different from the off the shelf Illinois.
Maybe they wanted to shave another $.030 off each crappy cap they had made for their application?
Maybe they are operating the caps too close to the working voltage limit?
Could be many things.
The number of users who use the Illinois and have had no issues speaks volumes.
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It's dectective work 101. If all the failures seem to come from one amp company (Fender) and most of them from one model (Blues Junior), it would be considered admissable evidence that Fender got a bad run of caps. I've never had a bad Illinois cap and I've used a lot of them. On the other hand, my son's first amp was one of the earliest Blues Junior's. I bought it for him new and it still is just fine... and doesn't sound bad either, BTW. I'd bet the amps with bad caps were all made about the same time. If so, I'd consider that proof!
Dave
I'm a retired investigator who repairs a lot of Fenders. I have observed failed IC caps in the Tweed/Hot Rod series of amps as well as the Blues Junior and one Custom Shop Tweed Twin. I wasn't keeping track but it would be fair to say at least 20 amps in the last five years. Most had some discharge from the positive end. I don't think IC caps are bad- Fender used(s) them exclusively in tube amps for 15+ yrs and I would say less than 1% of the Fender amps I've serviced had IC caps fail (amps dated from abt 1994-2010) Factor in the zillions that have not come in for repair and I bet any cap manufacturer would have the same or worse failure rate. I'm pretty sure that if IC's were bad, Fender would have switched vendors way before now. I replaced them with IC's, Spragues, and F&T (whatever I had in hand and fit) and none came back with the same issue. (I like F&T and Atoms in my builds but it's probably superstition)
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I use the JJ multisections for filter caps, except for bass amps and I've only gutted and rebuilt those so the cap cover was already there. I've never had a bad one. Doug sells them. They take up very little real estate and I like to make the amps as small as safely possible.
"Factor in the zillions that have not come in for repair and I bet any cap manufacturer would have the same or worse failure rate."
I agree. I've never gotten a bad electrolytic from anybody.
Dave
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>Maybe they are operating the caps too close to the working voltage limit?
I wondered about this too. I noticed from perusing various Blues Jr schematics that the voltage rating on the power rail caps is 450V on some schematics and 525V on others. What is the voltage spike = to before the tubes start conducting?
IC is just fine and dandy. I find it a little interesting that the only comparisons are drawn to Sprague and F&T. Nichicon and Chemicon both make a far superior cap, but only in radial leaded. From reading speculation sheets, Panisonic makes a good cap too but I have no experience with them.
Cap failure is nothing new to tube amps. We all know this to be true. We also know that Fender has a 60ish year history of power supplies that just barely cut it. Who is at fault, IC or Fender? Many would argue that a barely adequate power supply is a big contributor to tone. Personally I think a weak power supply is the root of all that is evil.
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It's dectective work 101. If all the failures seem to come from one amp company (Fender) and most of them from one model (Blues Junior), it would be considered admissable evidence that Fender got a bad run of caps. I've never had a bad Illinois cap and I've used a lot of them. On the other hand, my son's first amp was one of the earliest Blues Junior's. I bought it for him new and it still is just fine... and doesn't sound bad either, BTW. I'd bet the amps with bad caps were all made about the same time. If so, I'd consider that proof!
Dave
As a retired investigator I'd like to share my investigative results and conclusion. I don't have precise numbers but I have observed about 12 IC failures in Fender Tweed/Hotrod Dluxe and Dvilles as well as Blues Jr. ALso 1 Custom Shop Twin. Amps were produced in the 1994-2010 timeframe. I replaced them with ICs, F&Ts, and Atoms (whatever I had on hand and would fit) None came back for cap issues. I would say they accounted for < 1% of Fenders I serviced/repaired since 1994. Some residue or actual dishcharge of material, 120 Hz hum etc. So in my experience the observed fail rate is < 1%. Now factor in the thousands they have built that did not come into the shop. The fail rate drops below .001% Please stipulate that anyone's caps would fail at or above the same rate.
Fender has used IC's almost exclusively since 1994 in most of their tube amps. They would have switched vendors long ago if the product wasn't up to the job. I bought an early VibroKing (#488) and had issues w/reverb. I talked with Bruce Zinky and in the conversation mentioned the IC caps. Bruce told me to call him when one of them failed. I'm still waiting for one to fail...
My bet is the jury will find IC not guilty of bad cap charge. Of course, we all know that not guilty is not the same as innocent... (I use Atoms and F&Ts in builds, but it is probably cap profiling...Or superstition, or just habit. I can't say I heard any difference.) Interesting topic and responses.
Larry
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I talked with Bruce Zinky and in the conversation mentioned the IC caps. Bruce told me to call him when one of them failed. I'm still waiting for one to fail...
Is'nt he the guy who said in the book that he wrote on tube amps the way to discharge filter caps is to take a - Big - screw driver with a plastic handel and lean the shank of the screw driver on the side of the chassis and keep it there and then touch the tip of screw driver to the positive terminal of the filter cap. :w2:
Brad :think1:
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I talked with Bruce Zinky and in the conversation mentioned the IC caps. Bruce told me to call him when one of them failed. I'm still waiting for one to fail...
Is'nt he the guy who said in the book that he wrote on tube amps the way to discharge filter caps is to take a - Big - screw driver with a plastic handel and lean the shank of the screw driver on the side of the chassis and keep it there and then touch the tip of screw driver to the positive terminal of the filter cap. :w2:
Brad :think1:
Never read that one, Brad. :laugh: I guess it would drain them, but a bit noisy. No mention as to the status of the power and standby switches? Anyway, he called the IC cap quality right. I am new to this forum but so far I've seen a number of well-known-if-not-respected guys take hits. Of course, if the shoe fits they gotta wear it. This forum is no place for sensitive egos! They might be trying to make a buck, but who isn't? They all believed in their product. Thirty-five years ago, I would have died for the resources we have now on line or published books. On the other hand I could get a decent 7025 or 6L6 at the local drug store... Man, I should have bought those cases of tubes in the basement...
What I like(d) about Gerald, Fischer, and Pittman is/was their willingness to share their knowledge and experience with everyone. For the price of a guitar mag or the Angela catalog, you could get information that was not forthcoming elsewhere. The books came and I got a lot out of them. I now have a cabinet full of reference material. (The gem of my collection is most of the Fender service manuals and bulletins from about 1965 to 1985. Some stuff from FMIC. Inherited them when we discontinued being a service center.)
Well I think I gone on way too long. I appreciate the insight from all. (I'll probably keep using the Atoms and F&Ts, and yes, I use JJ's too- I forgot about them. I keep a few DeVilles worth of IC's in stock also. )
Semper Fi, Larry
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I talked with Bruce Zinky and in the conversation mentioned the IC caps. Bruce told me to call him when one of them failed. I'm still waiting for one to fail...
Is'nt he the guy who said in the book that he wrote on tube amps the way to discharge filter caps is to take a - Big - screw driver with a plastic handel and lean the shank of the screw driver on the side of the chassis and keep it there and then touch the tip of screw driver to the positive terminal of the filter cap. :w2:
Brad :think1:
On a slightly diff'rent tack, I have a standard bit screwdriver that someone tried that trick with in a Toyo Si150 injection molding machine's servo power supply rail by accident (it was locked and tagged out). It has a couple farads worth of 500V capacitors behind said rail... took a few minutes with a grinding wheel to fix it. I left a bit of the damage as a reminder to be more careful next time. Fortunatly the guy had hold of the insulation instead of the shank. I been looking at the caps on a fried servo amp, but the caps are a leeetle too big for thermonic work. <snicker>
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Probably not the "best" method to discharge a cap, but certainly the fastest. Reminds me of Discharging a CRT.
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I talked with Bruce Zinky and in the conversation mentioned the IC caps. Bruce told me to call him when one of them failed. I'm still waiting for one to fail...
Is'nt he the guy who said in the book that he wrote on tube amps the way to discharge filter caps is to take a - Big - screw driver with a plastic handel and lean the shank of the screw driver on the side of the chassis and keep it there and then touch the tip of screw driver to the positive terminal of the filter cap. :w2:
Brad :think1:
I accidentally crossed the terminals with a screwdriver tip on a big cannister cap in an old Yamaha G100-210 solid state amp I used to have and it went POP and blew a big chunk out of the tip of the screwdriver... I didn't get hurt and it didn't hurt the amp, but I sure wouldn't recommend discharging caps like that.
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Quote:"I've never gotten a bad electrolytic from anybody."
I have.A super reverb I re-capped had one bad 22uf/450v cap in it.The owner played it for an hour and then it emitted the magic smoke.I checked it over very thoroughly after and nothing was amiss.I replaced the cap and all was well.It's still ok after 5 years now.
It happens.Just not very often.
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Probably not the "best" method to discharge a cap, but certainly the fastest.
That has not only got to be hard on the screw driver, but very hard on the cap.
Brad :icon_biggrin:
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I can't remember the brand but I had a cap (installed correctly) that boiled over when powered up...