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#1
Posted to rec.audio.tubes
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Fun with caps...
François Yves Le Gal said:
It seems that the nice people at Vishay Sprague have more and more problems with their Atom line of elcos. Vide some from a recent batch with inverted shrink sleeves: http://www.aingeal.com/atom/Atom.jpg Hmmm. Wonder how many mismarked caps have shipped... Not restricted to BC/Vishay, I'm afraid. We've had this happen lately with Nippon Chemicon as well. Seems to be happening since the RoHS directive became effective. What the exact relation is, is still unclear. We sent the blown up smaples back to Japan for further study. -- - Maggies are an addiction for life. - |
#2
Posted to rec.audio.tubes
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Fun with caps...
"François Yves Le Gal" wrote: On Tue, 13 Feb 2007 23:50:47 +0100, Sander deWaal wrote: Not restricted to BC/Vishay, I'm afraid. We've fully tested all the Atom's we've received today and found another "mistake" : the 80 µF / 450 V are not 80 µF caps, they all measure between 46 and 54 µF and are very probably mislabeled 40 or 50 µF caps of unknown max V. Yeah, talk about American quality : I've never seen such problems with European caps from F&T or JJ. Never. Caps in crossovers from old speakers sometimes vary 100%. In AR12 speakers I recently re-engineered, I found huge variations on C tolerances. When I then measured the accumulated my stocks of old caps left over from other re-engineered other AR, JBL, and other brand speakers mainly from the late 1970s, the cap values were way out, and all needed relabelling so I know what experimental values I am using when I assemble the initial crossover for testing during re-engineering. New bi-polar electro caps of 22uF, 47uF etc made in Taiwan, measure nearly exactly right. This tells me the meter reads right, and the old caps are wrong, and probably were wrong when originally fitted. Old caps are a PITA. But recently, while examining Auricaps in a preamp where they were fitted last year during routine maintenance I discovered dc leakage where it simply shouldn't be. So some new caps are a PITA. Patrick Turner. |
#3
Posted to rec.audio.tubes
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Fun with caps...
"Patrick Turner" wrote in message ... In AR12 speakers I recently re-engineered, I found huge variations on C tolerances. When I then measured the accumulated my stocks of old caps left over from other re-engineered other AR, JBL, and other brand speakers mainly from the late 1970s, the cap values were way out, and all needed relabelling so I know what experimental values I am using when I assemble the initial crossover for testing during re-engineering. New bi-polar electro caps of 22uF, 47uF etc made in Taiwan, measure nearly exactly right. This tells me the meter reads right, and the old caps are wrong, and probably were wrong when originally fitted. Old caps are a PITA. In times past naive folks have replaced old caps with new caps and the sound of the equipment changed. Some of them ascribed the differences to esoteric effects like dielectric absorption, when in fact all they did is replace a 5 uF cap with a 10 uF cap in a circuit where the proper capacitance was 10 uF. Very few people who do "capacitor upgrades" on old equipment, and do it right. That means doing trivial checks on the old parts to see what their status was, as well as checking new parts to make sure they are what they claim to be. Good work, Pat! |
#4
Posted to rec.audio.tubes
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Fun with caps...
"François Yves Le Gal" wrote: Patrick Turner wrote: So some new caps are a PITA. Most so-called "audiophile" caps are basically overpriced junk. But they're hand wound by nubile virgins under the light of a full moon ! Surely that counts for something ? Did anyone else see the capacitor modification for electrolytics to 'improve the sound' that involved transplanting the guts into wooden tubes ? Graham |
#5
Posted to rec.audio.tubes
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Fun with caps...
Patrick Turner said:
So some new caps are a PITA. Sure. The Nippon Chemicons I mentioned earlier, are radial types in the series SMH. Some of them had the sleeve crimped 180 degrees. The only way to tell what's plus and minus is the structure of the mounting studs where the pins ate welded to the internal structure. Not something you'd expect assembly line people to look at....... 4700 uF/100V, 12 pieces in a symmetrical power supply is a lot of charge and energy when things go wrong. -- - Maggies are an addiction for life. - |
#6
Posted to rec.audio.tubes
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Fun with caps...
On Feb 13, 11:24 pm, Patrick Turner wrote:
Old caps are a PITA. So some new caps are a PITA. Test 'em coming out. Test 'em going in. The only way to fly. Peter Wieck Wyncote, PA |
#7
Posted to rec.audio.tubes
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Fun with caps...
Sander deWaal wrote:
Not restricted to BC/Vishay, I'm afraid. We've had this happen lately with Nippon Chemicon as well. The Atom line of Sprague Vishay capacitors are made by Nippon Chemicon aka United Chemicon, in North Carolina, and have been for a long time. So this is unlikely to be a coincidence. I would call these "Deputy Barney Fife" capacitors, Barney Fife not only was from North Carolina, Barney only had one bullet (in his pocket), and when he did try to use it, he tried to put it in his gun butt first. We sent the blown up smaples back to Japan for further study. "Smaples"? Something tells me they won't be transferring production to Holland to correct these production errors ;-) -- Ned Carlson SW side of Chicago, USA www.tubezone.net |
#8
Posted to rec.audio.tubes
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Fun with caps...
Eeyore wrote: "François Yves Le Gal" wrote: Patrick Turner wrote: So some new caps are a PITA. Most so-called "audiophile" caps are basically overpriced junk. But they're hand wound by nubile virgins under the light of a full moon ! Surely that counts for something ? Did anyone else see the capacitor modification for electrolytics to 'improve the sound' that involved transplanting the guts into wooden tubes ? Graham Some years ago I was asked to fully repair a couple of pairs of JBL speakers where the surrounds to bass drivers had rotted out, and in the process I checked everything else. I found there were coupling caps in series with tweeters which were plastic film caps but which were encapsulated in cardboard cylinders sealed at each end with cardbooard end plugs. Inside the cardboard tubes and surrounding the cap was an amount of what looked like Carly Fornia beach sand, because when I removed a cap that was stuck to a masonite circuit board of the Xover, the cardboard case tore open, and all this sand poured out. The sand must have been used to damp the capacitor's susceptibility for microphonic excitation by sound waves within the enclosure. Either that or the idea was something inneffectually dreamed up by a Carly Fornian resident's enthusiasm for elightenment effected with lsd or thc in the seventies. The crossover coils in series with bass speakers were about 1.8mH, and consisted of E&I laminations of 10mm stack, 6mm tongue, plus a few turns of thin wire. I figured that above very low levels, these would saturate with signal level and thus act as non linear filter devices so that the speakers were subject to expanded sound signals. After re-building the Xovers with all new LCR, the speakers did sound a lot better. Such speakers had about 1.5 cu. ft. enclosures, maybe 35Litres, but had 12" / 300mm dia bass drivers to boost bass, because a decent ported box would need to be 3 times the volume for a more flat response since the VAS was high... The speakers tended to have "one note" bass, and were not Carly Fornian boom boxes for nothing. They sold like hot cakes by the thousand.... But I digress from caps.... Boom chicka boom, boom chicka boom.... The Beach Boys spent several summers on beaches in Oz because there was a shortage of sand in the US. Patrick Turner. |
#9
Posted to rec.audio.tubes
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Fun with caps...
Patrick Turner wrote:
.... I found there were coupling caps in series with tweeters which were plastic film caps but which were encapsulated in cardboard cylinders sealed at each end with cardbooard end plugs. Inside the cardboard tubes and surrounding the cap was an amount of what looked like Carly Fornia beach sand, because when I removed a cap that was stuck to a masonite circuit board of the Xover, the cardboard case tore open, and all this sand poured out. The sand must have been used to damp the capacitor's susceptibility for microphonic excitation by sound waves within the enclosure. Either that or the idea was something inneffectually dreamed up by a Carly Fornian resident's enthusiasm for elightenment effected with lsd or thc in the seventies. Or was the sand just to fill out a larger package, so fooling the non-technical that this was a "better" capacitor? I've seen something similar done with batteries: a C-size cell put in a D-size casing, & sold at the D-size price. |
#10
Posted to rec.audio.tubes
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Fun with caps...
David R Brooks wrote: Patrick Turner wrote: ... I found there were coupling caps in series with tweeters which were plastic film caps but which were encapsulated in cardboard cylinders sealed at each end with cardbooard end plugs. Inside the cardboard tubes and surrounding the cap was an amount of what looked like Carly Fornia beach sand, because when I removed a cap that was stuck to a masonite circuit board of the Xover, the cardboard case tore open, and all this sand poured out. The sand must have been used to damp the capacitor's susceptibility for microphonic excitation by sound waves within the enclosure. Either that or the idea was something inneffectually dreamed up by a Carly Fornian resident's enthusiasm for elightenment effected with lsd or thc in the seventies. Or was the sand just to fill out a larger package, so fooling the non-technical that this was a "better" capacitor? No, No, No, the caps were hidden inside the speaker, and hardly anyone non technical had any idea what actually was inside there. Speaker makers often left out any serious attempt at x-over building, but with JBL at least there was a x-over; some speakers just had full signal to the bass, and 22uF to the treble, and 4uF to the tweeter, no impedance equalisation, and no inductors. In the 1970s, Marantz had a model with a bass and treble speaker with reflex port hole between the two with a grille over it to make it look like a midrange. Ppl were fooled, wow, a 3 way speaker! and it only a 4uF cap in front of the tweeter. But in fact it was about a 6 way speaker because each large thin box panel produced a range of frequencies.... I've seen something similar done with batteries: a C-size cell put in a D-size casing, & sold at the D-size price. Ah well, they probably sold them to deople with D-size brains. Patrick Turner. |
#11
Posted to rec.audio.tubes
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Fun with caps...
On Feb 15, 4:51 pm, François Yves Le Gal wrote:
On 14 Feb 2007 08:04:31 -0800, "Peter Wieck" wrote: Test 'em coming out. Test 'em going in. The only way to fly. Yup. A few years ago you could do some random testing. Now everything has to be tested. And all suppliers have gone ISO. Wonder if there's a connection? I am sure it is. ISO more-or-less works to some level of tolerable defects based on some level of testing. But with producers manufacturing for multiple labels with various degrees of tolerance, I can see that "first-run, fully tested" caps would be labeled to one supplier on that program, and "the rest of the crap" would be distributed amongst the peasants. Once upon a time a supplier would make their own products on dedicated lines with individuals trained at what they are doing. Today, just like the (actual event) Chevy Nova coming down the line as seen from the left and the Toyota Corolla coming down the line as seen from the right, that ain't necessarily so no more. When I am doing any sort of capacitor work from audio replacement and upgrading to shotgunning vintage radios, they are tested out and tested in. The small-value film caps are generally pretty good. The electrolytics... SHEESH... I am OK with +100/-20% tolerances for most applications, but these days I see far more +0/-40% than anything else. And boutique-caps are, if anything, far worse-by-test. Nichicon el-cheapos seem to test out the closest to label in my experience. Also US-made motor-run caps from my local motor rebuilder test out pretty close as well - but are real-estate pigs. Otherwise, it is a crap-shoot. Peter Wieck Wyncote, PA |
#12
Posted to rec.audio.tubes
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Fun with caps...
Ned Carlson said:
We sent the blown up smaples back to Japan for further study. "Smaples"? Something tells me they won't be transferring production to Holland to correct these production errors ;-) Damn lysdexia is playing up again. Should be smaples, of course. ;-) -- - Maggies are an addiction for life. - |
#13
Posted to rec.audio.tubes
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Fun with caps...
François Yves Le Gal said:
Should be smaples, of course. ;-) Snapples? Samples. ;-) -- - Maggies are an addiction for life. - |
#14
Posted to rec.audio.tubes
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Fun with caps...
"François Yves Le Gal" wrote: On Fri, 16 Feb 2007 18:37:00 +0100, Sander deWaal wrote: Should be smaples, of course. ;-) Snapples? Not to be cornfused with elmons, bacages, croboli, nabanas, wartsberries, aronges, sraep or retawmelons. More raviety can be found at Earth's rupple sister planet. Aptrick Urtner. |
#15
Posted to rec.audio.tubes
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Fun with caps...
"François Yves Le Gal" wrote: On Fri, 16 Feb 2007 23:38:17 GMT, Patrick Turner wrote: More raviety can be found at Earth's rupple sister planet. Smaple is the national tree of Scnadana, isn't it? No, its a nkid of kcor found in Uastrilaa. They nime it and its rowth a tol of nomey. The Hcinese yub it! Rickpat Nertur. |
#16
Posted to rec.audio.tubes
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Fun with caps...
"Patrick Turner" wrote in message ... Eeyore wrote: "François Yves Le Gal" wrote: Patrick Turner wrote: So some new caps are a PITA. Most so-called "audiophile" caps are basically overpriced junk. But they're hand wound by nubile virgins under the light of a full moon ! Surely that counts for something ? Did anyone else see the capacitor modification for electrolytics to 'improve the sound' that involved transplanting the guts into wooden tubes ? Graham Some years ago I was asked to fully repair a couple of pairs of JBL speakers where the surrounds to bass drivers had rotted out, and in the process I checked everything else. I found there were coupling caps in series with tweeters which were plastic film caps but which were encapsulated in cardboard cylinders sealed at each end with cardbooard end plugs. Inside the cardboard tubes and surrounding the cap was an amount of what looked like Carly Fornia beach sand, because when I removed a cap that was stuck to a masonite circuit board of the Xover, the cardboard case tore open, and all this sand poured out. The sand must have been used to damp the capacitor's susceptibility for microphonic excitation by sound waves within the enclosure. Either that or the idea was something inneffectually dreamed up by a Carly Fornian resident's enthusiasm for elightenment effected with lsd or thc in the seventies. The crossover coils in series with bass speakers were about 1.8mH, and consisted of E&I laminations of 10mm stack, 6mm tongue, plus a few turns of thin wire. I figured that above very low levels, these would saturate with signal level and thus act as non linear filter devices so that the speakers were subject to expanded sound signals. After re-building the Xovers with all new LCR, the speakers did sound a lot better. Such speakers had about 1.5 cu. ft. enclosures, maybe 35Litres, but had 12" / 300mm dia bass drivers to boost bass, because a decent ported box would need to be 3 times the volume for a more flat response since the VAS was high... The speakers tended to have "one note" bass, and were not Carly Fornian boom boxes for nothing. They sold like hot cakes by the thousand.... But I digress from caps.... Boom chicka boom, boom chicka boom.... The Beach Boys spent several summers on beaches in Oz because there was a shortage of sand in the US. Patrick Turner. The sand was a feeble attempt to cut down on microphonics. west |
#17
Posted to rec.audio.tubes
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Fun with caps...
west wrote: The sand was a feeble attempt to cut down on microphonics. What microphonics ? Graham |
#18
Posted to rec.audio.tubes
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Fun with caps...
west wrote: "Patrick Turner" wrote in message ... Eeyore wrote: "François Yves Le Gal" wrote: Patrick Turner wrote: So some new caps are a PITA. Most so-called "audiophile" caps are basically overpriced junk. But they're hand wound by nubile virgins under the light of a full moon ! Surely that counts for something ? Did anyone else see the capacitor modification for electrolytics to 'improve the sound' that involved transplanting the guts into wooden tubes ? Graham Some years ago I was asked to fully repair a couple of pairs of JBL speakers where the surrounds to bass drivers had rotted out, and in the process I checked everything else. I found there were coupling caps in series with tweeters which were plastic film caps but which were encapsulated in cardboard cylinders sealed at each end with cardbooard end plugs. Inside the cardboard tubes and surrounding the cap was an amount of what looked like Carly Fornia beach sand, because when I removed a cap that was stuck to a masonite circuit board of the Xover, the cardboard case tore open, and all this sand poured out. The sand must have been used to damp the capacitor's susceptibility for microphonic excitation by sound waves within the enclosure. Either that or the idea was something inneffectually dreamed up by a Carly Fornian resident's enthusiasm for elightenment effected with lsd or thc in the seventies. The crossover coils in series with bass speakers were about 1.8mH, and consisted of E&I laminations of 10mm stack, 6mm tongue, plus a few turns of thin wire. I figured that above very low levels, these would saturate with signal level and thus act as non linear filter devices so that the speakers were subject to expanded sound signals. After re-building the Xovers with all new LCR, the speakers did sound a lot better. Such speakers had about 1.5 cu. ft. enclosures, maybe 35Litres, but had 12" / 300mm dia bass drivers to boost bass, because a decent ported box would need to be 3 times the volume for a more flat response since the VAS was high... The speakers tended to have "one note" bass, and were not Carly Fornian boom boxes for nothing. They sold like hot cakes by the thousand.... But I digress from caps.... Boom chicka boom, boom chicka boom.... The Beach Boys spent several summers on beaches in Oz because there was a shortage of sand in the US. Patrick Turner. The sand was a feeble attempt to cut down on microphonics. west Had they placed the whole crossover in a box screwed to the outside of the speaker where it is away from the loud sound levels **inside** the box, and then filled the whole box with sand, they'd have been more effective at reducing microphonics. Not even the beach babes would have had anywhere to sunbake, and think of the dissapointment that would have caused! Patrick Turner. |
#19
Posted to rec.audio.tubes
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Fun with caps...
Eeyore wrote: west wrote: The sand was a feeble attempt to cut down on microphonics. What microphonics ? Graham Low level ones. Sound excites caps so plate dimmensions change which dynamically phase modulates the sound signals. Coils of wire in inductors rattle around to change L, so more phase twitching. Not a big issue though eh. Patrick Turner. |
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