I just got a box of dryer sheets. Have not been zapped since, as long as I touch the sheet with each hand. Great suggestion. Thanks!
Help me solve static electricity problem
Lately I keep sending my Classe Amp and/or conrad-johnson preamp into protection mode simply by touching anything in my system. A loud pop goes through my speakers and it's very, very disconcerting. I'm smart enough to try to touch something metal before touching my rack, but this does not always work. Apparently I'm not smart enough to solve this condundrum, though. Any ideas????
56 responses Add your response
All I can say is that rubbing a dryer sheet on my hands before I touch a component has been foolproof since i started this thread a year ago....and my static problem was severe. I'd be interested in hearing from anyone for whom this dyi fix has not worked...just in case I shouldn't consider it a panacea. |
Other than wearing rubber soled shoes, a grounding strap, remembering to discharge oneself to ground, or treating oneself, carpeting and furniture to reduce static buildup, is there any component, device or circuit that could replace the "capacitor idea" in my previous design to absorb and pass the discharge to ground without creating a ground loop or other ill effect?It seems to me that the use of braided ground straps from each chassis to a common ground point, as I described above, might do exactly that in many cases. Why are some components less susceptible than others?Good question. My feeling is that the root cause of these problems is most likely the failure of the designers of equipment that is susceptible to this problem to adequately address the issue during the design process. It's interesting that computers, which contain digital devices and circuits that are much more complex than in most audio components, and that run at much higher frequencies, never (to my knowledge) seem to have these kinds of problems when their metal cases are touched. Makes you wonder. Best regards, -- Al |
Thanks for the response. I'm not really sure how a capacitor might work in this situation is why I asked. I was wondering if there was a way to "grab" the static discharge absorbed by chassis and pass it to electrical ground before it got into the signal causing a loud pop without potentially creating a ground loop between any components. This was a "Hail Mary" idea of mine for Vhiner's problem. I imagined at least one of his components was highly susceptible to this problem because I have taken some real painful shocks in the past and never heard anything through my speakers, much less engaged protection circuitry. My approach was to search for a simpler, more user friendly way to manage this problem other than remembering to discharge oneself before touching anything. I was also looking for a solution that would work whenever an unfamiliar guest reached for the volume control. Believe it or not, I briefly considered metallic doors that would force the user to discharge themselves to ground before touching any equipment. As sure as I am that would work, even I wouldn't do it myself. Other than wearing rubber soled shoes, a grounding strap, remembering to discharge oneself to ground, or treating oneself, carpeting and furniture to reduce static buildup, is there any component, device or circuit that could replace the "capacitor idea" in my previous design to absorb and pass the discharge to ground without creating a ground loop or other ill effect? Why are some components less susceptible than others, and can that be applied here? |
Isn't static at very high voltage?Yes. Would a cap simply look like a resistor to a very high voltage...even if the current were essentially zero?It would look like some combination of capacitance, inductance, and resistance, with various resulting overall impedance magnitudes and phase angles at each of the many frequency components of the static discharge. But since those impedances together with the impedance of the connecting wires would be higher than that of a heavy gauge wire by itself, and much higher than that of a braided ground strap, the capacitor would serve no purpose. Re the Zerostat, keep in mind that what we are trying to de-staticize here is the person! Best regards, -- Al |
Isn't static at very high voltage? Would a cap simply look like a resistor to a very high voltage...even if the current were essentially zero? We had static problems at work and a bigtime solution in the form of HV electrodes protruding into the airflow...it was a top to bottom 'laminar' flow ROOM. We also had a little gun....called a 'ZeroStat' which was effective in the reduction static charge on say....Teflon Cassettes, used to hold silicon wafers. The static would attract dust like a mad dog. http://www.2spi.com/catalog/photo/zerostat.shtml |
12-12-10: HeyrazThat's an imaginative thought, but I don't think it would help. Basically a capacitor acts like an impedance whose value decreases as frequency increases. So it would shunt high frequency energy to ground, within the constraints presented by the inductance of the associated wiring. But the safety ground wiring that is already present will do the same thing, except better since it will conduct low frequencies in addition to high frequencies. A device called a Transorb is commonly used for dealing with brief but large voltage spikes, but determining how to best apply one within a particular piece of equipment would be problematical. One approach that I think might work in many cases is a variation of Kijanki's earlier suggestion, about lowering the impedance of the path between each chassis and a common ground point (such as the screw on a wallplate, or the chassis of a power conditioner). But my suggestion would be to do that with braided rf ground straps, rather than heavy gauge wiring, connected in a star pattern as Kijanki suggested. That would present a path for the extraneous currents that is truly low impedance at high frequencies. Industrial distributors such as Digikey carry ground strap material, but typically in large quantities. It is offered in smaller quantities by a number of eBay sellers -- search under "ground strap." Regards, -- Al |
Anyone with knowledge of Capacitors? What would happen if the chassis of each component were connected in starfish pattern through capacitors to one central ground point and then on through another capacitor to a common ground? Would the capacitors act to absorb the static discharge and then slowly release them to ground? I'm not 100% sure how caps work but they seem to behave like water hammer arrestors sometimes. |
I got a nice Parasound A23 amp and P3 preamp pair from this site. As soon as last winter arrived, one modest static touch blew out the pre, to the tune of a $300 repair. I tried to be careful afterwards to discharge before I touched it. But, alas, first cold day this winter I transmitted a static charge so small I could barely feel it, and poof! flashing lights, preamp dead again. I've had it now, and rather than repair, I would like to replace the preamp with a different brand/type that isn't so susceptible to static electricity damage. All advice welcome. |
Puremusic, If you read kijanki's explanation of this, it sounds complicated and dangerous if you don't really know what you're doing. I'm absolutely NOT a DYI'er...so I'm not sure who I'd pay and trust to do this properly. Again, the dryer sheets seems to have solved my problem..but I'd like to be able to do the ultimate fix if it's necessary. |
"So my wool rug is the problem, . . . " Indeed, I had what I thought was a serious issue with a piece of my equipment that through trial and error, tracked it down to static. And more interestingly, by design I could drag my 'slippered' feet (didn't work with socks or bare foot) across 35 ft of my wool rug and give my finger enough of a jolt that it would be uncomfortable for a day or so. So I did it again just to be sure . . . . . . ha |
It has been very cold here and I have been having a variant of this problem that drove me nuts till I figured out what was going on. I would play one side of an LP and when I put the next side on a channel would be out. I finally realized that the static discharge when I touched either my phono stage or int. amp would mute one channel. When I would turn the phono stage off and then back on the channel was back. Also it affected only the MC and not the MM. So my wool rug is the problem, when I move the phono stage to another location no problem at all, it may be in the amp or somehow in the interaction of the two. If you are having mysterious problems this time of year it may be static electricity. |
I too may have been having a static problem. Just started testing a new (used) Sonic Frontiers Preamp and the thing went to full volume before the APC power conditioner shut everything off in a fraction of a second. I had read that there was an issue with the attentutor being defective on some Line 2 machines. The designer offers a $300 fix. So now I am unsure if it is the static or the volume control electronics acting up? |
I was also having static shocks, some strong enough to reset my Plinius integrated out of standby. Strongest shocks, and the ones causing concern, were coming off of a PS Audio Humbuster, but shocks off pretty much anything metallic. Not unexpected as winter on the edge of the prairie is dry and cold, and wool carpeting compounding it. Spoke to Plinius and they indicated it is technically possible if a strong enough shock i.e not something wrong with the amp or the system. As with another post, amazing discovery was that I only got these shocks when wearing slippers or shoes with synthetic soles. Barefeet or socks = no static shocks at all. So I live with it. |
Just an update for anyone interested: after two weeks, no pops at all and the weather is colder and dryer than ever. The only change has been the use of a dryer sheet on my hands before touching components and making sure NO cables are touching each other. Thanks to everyone who contributed. Hope this helps someone else. |
Just a quick update. I've not encountered a static charge since moving several of my cables and using dryer sheets on my hands before touching components...but it's still early days. I plan on checking out a humidifier, as well as a grounding mat if I can find unobtrusive locations for them. Kijanki..I appreciate the technical detail and will be sharing it with an electrician if the problem doesn't resolve. Please keep the ideas coming. All of you are what makes a'gon so great! The humor has also been appreciated. |
Vhiner - when you touch metal (case) in your system static creates huge current that is "looking" for very fast (nanoseconds)return to earth ground. It always finds many returns and current divides in order of paths' impedance. In your system case ground connects to conditioner (cable inductance) and then from conditioner to wall outlet (again cable inductance). It gets worse when cables are longer (like 6') because folded cable has even more inductance than straight one. To lower this big current going thru your PCBs circuit grounds (and creating voltage drops)and then transformer's capacitance to neutral of power cable - lower inductance of your chassis ground return by grounding it separately with short wires to earth ground (ideal if close)or third prong of your wall outlet. Use star grounding of all components (do not daisy chain grounds). Verify that your outlet's box has good ground return (conduit might be loose etc.) Use decent gauge (at least 16) since currents are huge and thicker wire has a little lower inductance. After that, there will be still multiple return paths during static discharge with one going thru PCBs' grounds and circuitry (this is more like wave that goes everywhere) but current ratios will be different and your protection might stop triggering. |
You're right, Jea48, but there are room humidifiers and there are room humidifiers. The TWO Bionaire units I had originally were only barely able to keep the relative humidity above 30% in my listening room and I could still mute the CJ preamp by touching it, a tonearm, the front of a tape deck, or practically anything else in the system made of metal. |
I have switched to a wool rug for the sonic benefit, happy with it but am getting a similar effect in the very dry conditions of the cold weather we are having. I can unmute my MF M3 amp just by touching it. This, obviously,is not a desirable effect but has not risen beyond the irritating level so far. However, a friend had a CD player damaged by something similar so there is some cause for concern. Moisture should help as suggested above, I have one of the old static guns and I think I will try using it on myself before I touch the amp. I just thought of this, it is surly an improvement on my my original plan of a long ground wire attached to my posterior. |
Vhiner, Like others have said just add humidity to the room. The static charge is a good warning the air in the room is too dry. Really dry air can cause damage to wood speaker cabinets as well as fine wood furniture. I would also think the dry air would not be good for a driver speaker surround. Buy a humidifier as well as a humidity sensor. Example of a humidity sensor. http://www.indoorhealthproducts.com/humidity-sensors-buying.htm |
I had exactly the same situation with a CJ preamp (Premier 17LS2) and "solved" it only by getting an Aesthetix Calypso and selling the CJ. Mine muted itself even when I touched the SPEAKERS. I tried everything, even had anti-static copper tinsel (very festive) strewn around everywhere. I've had static problems since then, but not nearly as severe, and attacked them with reasonable success using room humidifiers (plural). I tried this with the CJ in place, too, but replacing it, which I loved for its sound, was the only way to go, for me. The temporary fixes -- antistatic guns, clothing, rugs, shoes, sprays, incantations -- made me feel like I was attacking the problem but didn't do a whole lot to overcome it. Oh, and there's one other thing that will fix everything: the coming of spring. Good luck, Dave |
Your equipment is not defective. I live in Arizona and have the same problem and have read of others having the same problem. You just have to find a way to discharge your static electricity before touching your gear. I rap a knuckle against a metal post on my equipment rack. Since our knuckles are less sensitive than our fingertips this eliminates the little sting you get when you touch a fingertip. |
Vhiner -- Well, with all of that good protection and filtering, most likely one of the possibilities I was envisioning, that you have a damaged line bypass capacitor in one of the components, can be ruled out. That was why I asked about surge protection, and also about the age of the equipment. However, the fact that everything is separately filtered, and the power amp is on a separate dedicated line, increases the likelihood of noise voltages developing between the chassis and circuit grounds of the different components. The degree to which that might happen would depend on the shield resistance of the interconnect cables, which connect the component chassis together. That is why I asked about the possibility of a damaged interconnect. I'm envisioning that the rfi (radio frequency interference) generated by a static discharge could induce noise into any susceptible point in the system, which would then get amplified by everything downstream, causing the pops you hear. A phono input would be a likely suspect, because of the high gain factor that is applied to it. So besides continuing the interconnect experiments you are already doing, I would suggest: -- Putting shorting plugs on any unused phono inputs, and/or disconnecting any used phono inputs and putting shorting plugs in place of the cables from the turntable. -- Disconnect all source components from the preamp, and see if you still get the symptoms when the preamp or power amp is touched. -- Disconnect the preamp from the power amp, and see if you still get the symptoms when the power amp is touched. -- As an experiment (to help in diagnosing the problem) plug the entire system into the Guardian, assuming it has enough current capability, and see if you still get the symptoms. Hope that helps, -- Al |
How about an antistatic mat in front of your rack? http://www.americanfloormats.com/corrugated-static-dissipative-runner-mats/ |
Thanks for all the responses. I'll pass on the rubber suit and naked listening...even *my* wife isnt't that patient. LOL. I'm using two separate 20-amp lines and Shunyata power conditioners on each line. The Classe runs through a Guardian and the rest of the gear runs through a Hydra Version II. I've got everything on a seperate filter. I just discovered that my digital interconnect was touching the single-ended interconnects that run from my preamp to the amplifier. This digital interconnect does not appear to be particularly well shielded. Hmmm. I moved it and will monitor...I've also repositioned several other interconnects. What do you think, Al? |
I agree with Al- a static shock should not cause your system to go into protection. My guess is something else is wrong. Where I live low RH is just a fact of life in the winter, and even though I run 3 humidifiers shocks happen regularly. All of my electronic components have recieved several shocks and I have never heard any pops or had any problems with them. Mark |