Hello All,
I am in a quandary, I know there has been, and continues to be much discussion about electrolytics. I know there are some very educated users in this forum, and so I am asking for advice. I have a 30 yr. old Hafler 110 pre-amp & 500 Amp that I am still currently using, and they are working fine. It has been suggested that I replace all the electrolytics in the units, as the life-span has expired. I opened the cases, and the pre-amp has IC (Illinois Capacitor) 105* caps, and they look brand new. From what I have researched, the 105’s have a longer life span than most 85’s out there today. I put this together as a kit, and have always been in possession of it since new, and this equipment has never seen any adverse conditions.
So what are the ramifications of continuing to use it “as is” or change out the caps? Is there a qualitative difference between caps? Or is it all subjective to “ear” differences?
Thank you in advance for any input.
I am in a quandary, I know there has been, and continues to be much discussion about electrolytics. I know there are some very educated users in this forum, and so I am asking for advice. I have a 30 yr. old Hafler 110 pre-amp & 500 Amp that I am still currently using, and they are working fine. It has been suggested that I replace all the electrolytics in the units, as the life-span has expired. I opened the cases, and the pre-amp has IC (Illinois Capacitor) 105* caps, and they look brand new. From what I have researched, the 105’s have a longer life span than most 85’s out there today. I put this together as a kit, and have always been in possession of it since new, and this equipment has never seen any adverse conditions.
So what are the ramifications of continuing to use it “as is” or change out the caps? Is there a qualitative difference between caps? Or is it all subjective to “ear” differences?
Thank you in advance for any input.
Electronlytics are an aluminum can full of water and borax or something more modern, sealed with an elastomer at the end and leads. Early elastomers were very short life. Based on my 1961 dynakit st70, that was 1/3 power in 1973 when the Mcintosh salesman tested it, tall can caps were good for about 10 year. Much progress was made in chemistry since 1961. Nevertheless, 1000 hour and no rated hour electrolytic caps continue to be sold, because the cheap rubber is cheap. My apex DVD converter came directly from w*** M*** with bad electrolytics caps, ie the diagonal lines would go away after it warmed up.
Particular caps can be rated as high as 8000 hours now, at 105 deg C. I don't know what chemical they use to seal the end, but it is better than the red glyptol (hoary technician joke rubber from 1972).
when electrolytics on the main input evaporate dry and short, if you are lucky the silicon rectifier blows. If you are not lucky, the transformer burns. If you intend to keep your caps because of reputation, I would put a fuse after the transformer and before the rectifier. Or you could buy a rectifier with a defined fusing current, as so many in switching power supplies have now. See for example the KBJ606 bridge rectifier from diodes inc with a fusing rating of 120 amp^2sec. Datasheet is on datasheetcatalog.com. I salvaged my KBJ606 from a PCAT switching power supply.
I replaced 70 electrolytic caps in my 1968 Hammond H182 organ. It sounded like a kazoo when I bought it. The first 4 can caps doubled the power. I replaced the first 4 caps in the power supply, with film caps, so huge I had to put them in a separate chassis. Bet they never blow up. Two more cans doubled the power again and added some bass to the tinny sound. The can cap on the percussion amp made the percussion work again with no diagnosis required. The bypass and coupling caps on the SS preamps, added more bass and treble. Replacing the axial caps in the power amp added more bass, and made the string bass sustain feature work. I still have to do 115 $6 electrolytics in the harp feature, as my buddie's H112 sounds better than mine with 1968 caps. Incidently, tantalum electrolytic cathode bypass caps in the power amp were replaced by factory service in 1970, 1972, and 1973. The last one lasted until last year. What a waste of service time and driving around los Angeles. The tantalums should have all been done in 1972.
The electrolytic motor start cap on the organ, shorted in 1997 and burned the wiring harness leading to the cap. Dealer service replaced it in 1997, but did not replace the insulation on the burned wires. I replaced it again in 2010, with a film cap. The organ will jiggle your belly with the bass now, on the stock 15" speaker. Take that, B3 owners.
The second H182 organ (with an intact case) has had one can cap replaced by axials and the motor cap replaced by film. It is fairly bassless, and generally sounds tired, as the reviews of H100's on the internet all complain about.
Particular caps can be rated as high as 8000 hours now, at 105 deg C. I don't know what chemical they use to seal the end, but it is better than the red glyptol (hoary technician joke rubber from 1972).
when electrolytics on the main input evaporate dry and short, if you are lucky the silicon rectifier blows. If you are not lucky, the transformer burns. If you intend to keep your caps because of reputation, I would put a fuse after the transformer and before the rectifier. Or you could buy a rectifier with a defined fusing current, as so many in switching power supplies have now. See for example the KBJ606 bridge rectifier from diodes inc with a fusing rating of 120 amp^2sec. Datasheet is on datasheetcatalog.com. I salvaged my KBJ606 from a PCAT switching power supply.
I replaced 70 electrolytic caps in my 1968 Hammond H182 organ. It sounded like a kazoo when I bought it. The first 4 can caps doubled the power. I replaced the first 4 caps in the power supply, with film caps, so huge I had to put them in a separate chassis. Bet they never blow up. Two more cans doubled the power again and added some bass to the tinny sound. The can cap on the percussion amp made the percussion work again with no diagnosis required. The bypass and coupling caps on the SS preamps, added more bass and treble. Replacing the axial caps in the power amp added more bass, and made the string bass sustain feature work. I still have to do 115 $6 electrolytics in the harp feature, as my buddie's H112 sounds better than mine with 1968 caps. Incidently, tantalum electrolytic cathode bypass caps in the power amp were replaced by factory service in 1970, 1972, and 1973. The last one lasted until last year. What a waste of service time and driving around los Angeles. The tantalums should have all been done in 1972.
The electrolytic motor start cap on the organ, shorted in 1997 and burned the wiring harness leading to the cap. Dealer service replaced it in 1997, but did not replace the insulation on the burned wires. I replaced it again in 2010, with a film cap. The organ will jiggle your belly with the bass now, on the stock 15" speaker. Take that, B3 owners.
The second H182 organ (with an intact case) has had one can cap replaced by axials and the motor cap replaced by film. It is fairly bassless, and generally sounds tired, as the reviews of H100's on the internet all complain about.
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When they say some part has a 10 year life span, it doesn't mean that a day after the tenth year ends the caps explode. It means that under average conditions, a reasonable expectation might be 10 years before performance starts to degrade. I have a 5 year battery in my car, and I certainly do not expect the battery to go dead as year 6 starts. And since I just love analogies, if my steak tastes good, should I dump salt on it because people tell me "all steaks need salt"?
If you recap your amp, it will sound good. But it sounds good now, so if it ain't broke, don't fix it. SOme people will make a case that changing them now will prevent a cap from failing outright in the future. Maybe, but my experience is that the caps are more likely to simply fade away over time.
If you recap your amp, it will sound good. But it sounds good now, so if it ain't broke, don't fix it. SOme people will make a case that changing them now will prevent a cap from failing outright in the future. Maybe, but my experience is that the caps are more likely to simply fade away over time.
be prepared, becauase that what they do
what happens is, one day it runs fine, and the next day it wont start 🙁
but supply caps are different, for sure
consider that the 80 - 105degr is exstremely hot
a cap that endures many many hours under such conditions could probably last forever
unless they leak ofcourse
might be equally or even more important to notice storage life
some caps are new when you buy the, some are not
I have noticed a German company Buerklin
every cap the sell are clearly marked with year of stock
I think most 105degr will be relatively new
and many 85degr could be older stock
older caps might be ok
but you have know about reforming proceedures
but even if working fine they may already have shortened life span
thats why you will find storage specs in the spec sheet
beyond those, thee promissed specs may not hold any longer
they might, and might not
with my limited skills I try to stick to new and trust worthy caps
and pay what they cost
I have a few stories. One,
I have a The Fisher transistorized amp from 1968. All components are originals, including the capacitors, which are Mallorys, if I recall correctly. I used the amp pretty extensively, and I've really cranked the hell out of it, especially back in my younger years. (1/4 volume = instant ear drum rupture).
After almost 50 years of use (not all from me, I'm not that old), does it sound any worse? Well I can't really tell...and maybe that's a good thing. But it still cranks and it still has an amazing punch to it.
And that's a 50 year old amp.
Earlier this year, I opened up an el cheapo Logitech 2.1 system, and was dismayed by the crap components inside...so I decided I would put some decent capacitors on there, and get it up to my standards...
Problem was, this thing was not meant for rework, and I wound up either shorting something or frying something, because it doesn't work now! Now if I had only left it alone...it would have been fine. Luckily, that only set me back a few bucks. But with something like your amp, why take the risk? As they say, if it aint broke, let it be. Only until it dies, or you hear some significant drop in performance would I replace the capacitors.
That being said,
if you do replace the capacitors, go value for value, and make sure to distinguish between polarized electrolytic and non polarized electrolytic, so you can replace accordingly. There's a good chance that there is ONLY polarized electrolytics on your amp, but just in case...
The general consensus is to use Panasonic FM, FC, as well as FR, which is essentially FM with a longer load life. Only downfall to FRs is that they are pretty ugly, if you care.
If you want to be cheaper, use Nichicon HE or PW. HE is pretty much equivalent to FM and PW is pretty much equivalent to FC....but I'd use the Pannys if you can get em. Either way, it'll work, though, and sound good.
Illonois Capacitor is a good brand, so I doubt any of them are dead. Maybe their electrolyte has gotten a bit dried up, but other than that...
Well good luck!
I have a The Fisher transistorized amp from 1968. All components are originals, including the capacitors, which are Mallorys, if I recall correctly. I used the amp pretty extensively, and I've really cranked the hell out of it, especially back in my younger years. (1/4 volume = instant ear drum rupture).
After almost 50 years of use (not all from me, I'm not that old), does it sound any worse? Well I can't really tell...and maybe that's a good thing. But it still cranks and it still has an amazing punch to it.
And that's a 50 year old amp.
Earlier this year, I opened up an el cheapo Logitech 2.1 system, and was dismayed by the crap components inside...so I decided I would put some decent capacitors on there, and get it up to my standards...
Problem was, this thing was not meant for rework, and I wound up either shorting something or frying something, because it doesn't work now! Now if I had only left it alone...it would have been fine. Luckily, that only set me back a few bucks. But with something like your amp, why take the risk? As they say, if it aint broke, let it be. Only until it dies, or you hear some significant drop in performance would I replace the capacitors.
That being said,
if you do replace the capacitors, go value for value, and make sure to distinguish between polarized electrolytic and non polarized electrolytic, so you can replace accordingly. There's a good chance that there is ONLY polarized electrolytics on your amp, but just in case...
The general consensus is to use Panasonic FM, FC, as well as FR, which is essentially FM with a longer load life. Only downfall to FRs is that they are pretty ugly, if you care.
If you want to be cheaper, use Nichicon HE or PW. HE is pretty much equivalent to FM and PW is pretty much equivalent to FC....but I'd use the Pannys if you can get em. Either way, it'll work, though, and sound good.
Illonois Capacitor is a good brand, so I doubt any of them are dead. Maybe their electrolyte has gotten a bit dried up, but other than that...
Well good luck!
105 deg caps and 85 deg caps have all been made for 40 years. I don't buy surplus or old stock caps, life is too short. Oxygen in the air attacks the rubber right in the box.
Reforming is fine for the aluminum and borax, but doesn't do anything for the deterioration of the rubber seals.
I had a friend paid a $100 premium for a 1970 H300 organ that according to the dealer "sounded great". It did, when he bought it. A month later, the kazoo effect had taken over, the bass and treble were gone. My theory is lightly used caps contained water when he bought it, but heating them up by actually using it evaporated the water right past the aged rubber seals.
Panasonic makes some good caps, but the ones in AB motor drives used in ovens are nichicon, producing life of over 10 years in a rediculously hot area. Nichicon makes 1000 hour caps and 8000 hour caps, you get what you pay for. Part number matters. The NHG panasonic datasheet I have, some caps are 1000 hours and others are 2000 hours, based upon capacitance size. 1000 years could be used up in one year. So both Panasonic and Nichicon make short life and long life caps, the details of the part number matter.
99.9% of electrolytic caps gently fade away, but when they blow up, they make a *** awful mess to clean up, as borax water is conductive and corrosive. The aluminum foil that spools out and shreds also has to picked up bit by bit. See "cap explosion" on the Hammond and Leslie threads of organ forum. For transistor circuits, I've also seen some motor drives where this happened. The caps in the power supply near the power transformer are the ones most likely to do this. If you like your gear, you really don't want to clean up after a cap explosion.
When I recap, I do one or two and then reassemble and listen to it to make sure I didn't make it worse. If I did put a cold solder joint in, or an incompatible part, or make a wiring error, I go right back and fix it then, I don't abandon the project. I draw out the circuit before I take it apart, those with close focus camaras could use them to good effect. If something I just did makes something worse, if I only did one or two things then I know pretty well where the problem is and can focus carefully to rework it.
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Thank you for all your replies, you have re-assured me that leaving this working amp will be fine; I will just keep an eye on the caps periodically inspecting them, and when I see / hear any signs of EOL, I will then re-cap. Thanks. 
One would be a fool to replace caps without measurements. One would be a fool to replace caps where the dissipation factor was acceptably low and the capacitance was within spec. Age means nothing because some electrolytic caps are bad two years out and others show no faults at 50 years. You can even be sure that good caps that have been in service a while will have lower leakage than brand new caps, that won't exhibit their lowest leakage until they've been under voltage for a few weeks. You can also be sure that, unless the tech is an absolute artist with a soldering iron, the PCB will be in poorer condition after a recap, than before.
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