ericn
Temp
Balance Engineer
Posts: 16,098 
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Post by ericn on Jan 29, 2024 20:08:54 GMT -6
The only real cure for grounding issues is a decent ground, depending on age of building it would in way suprise me if some did what we in Galveston referred to as “ an Island complete re wire”, this where someone replaces all the Metal outlet boxes with plastic and all the 2 prong outlets with 3 and the ground just hangs. The bad news, HVAC is one of the worst sources of problems, that and restaurant equipment and if someone has an old school fluorescent tube light grow house. Oh yeah if the space has fluorescent even the compact fluorescent bulbs get rid of them. Also and this is one that always crops up if you don’t check, make sure all the outlets on the circuit are in your room. I had a customer many years ago who had intermittent power issues, the problem was the circuit in his apt living room also was strung through the wall to a hallway outlet. The cleaning lady used that outlet for a crappy vacuum, that was the source of his intermittent pops and hum. Very, very interesting. I know for a fact that all there are outlets on the circuit not in our room. Well not for a fact, but I'm pretty sure. Because when the light to the storage closet goes on, it also flips a (you guessed it) horrid fluorescent light on in our room. Now, that rarely happens when I'm in there, but I have no idea what else is plugged in in that room. I will check that out for sure. Incidentally that room also has a vacuum cleaner that goes back to Egyptian antiquity but I've never seen it used. While not sexy in the least most of the time tracking circuits can yield real answers vs just buying expensive band aids. A fact that few realize is almost all possible power solutions are current limiting devices, usually it’s not the breakers that’s limiting the current. The other day I was looking at the PCB from my 20 amp Furman conditioner, can’t believe that thing is rated for 20amps! |
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Post by lee on Jan 29, 2024 22:39:04 GMT -6
Iso transformer is the right way to do it at scale, assuming ground and wiring are not your problem.
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Post by mattbroiler on Jan 30, 2024 2:34:48 GMT -6
For more around the $1000 price you can get the Furman P 1800 PF R furmanpower.com/product/15a-prestige-power-conditioner-w-power-factor-technology/Sweetwater has it on sale for $750 at the moment and I got mine for $500 on ebay This one actually conditions the power rather than being a glofiried power strip - it stores the incoming power in capacitor banks and doles it out in the proper levels. Another older model that has done similarly well for me is the Furman AR-1215 perhaps you can find some deals on ebay or REverb for these units Battery backup ups's a good idea for running computers and internet gear through but not amplifiers hell no. Another thing I discovered during our recent Oregon ice storm - at one point the house power/studio room developed some incredible noise despite running through the aforementioned Furman devices - loud hum crackling and seemingly compromised/bad grounding due to who knows what going on with the outside line coming into the house. Turning off all the music gear and shutting off that circuit breaker briefly then turning it back on cleared things up. I have a separate breaker circuit for the music room/computers so it is not shared with the house lighting and other stuff. This depends on whether you have access to the circuit breaker for your space and is not a guaranteed scientific fix but it worked for me that time to clean up the dirty power whatever was going on. |
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Post by svart on Jan 30, 2024 8:01:14 GMT -6
For more around the $1000 price you can get the Furman P 1800 PF R furmanpower.com/product/15a-prestige-power-conditioner-w-power-factor-technology/Sweetwater has it on sale for $750 at the moment and I got mine for $500 on ebay This one actually conditions the power rather than being a glofiried power strip - it stores the incoming power in capacitor banks and doles it out in the proper levels. Another older model that has done similarly well for me is the Furman AR-1215 perhaps you can find some deals on ebay or REverb for these units Battery backup ups's a good idea for running computers and internet gear through but not amplifiers hell no. Another thing I discovered during our recent Oregon ice storm - at one point the house power/studio room developed some incredible noise despite running through the aforementioned Furman devices - loud hum crackling and seemingly compromised/bad grounding due to who knows what going on with the outside line coming into the house. Turning off all the music gear and shutting off that circuit breaker briefly then turning it back on cleared things up. I have a separate breaker circuit for the music room/computers so it is not shared with the house lighting and other stuff. This depends on whether you have access to the circuit breaker for your space and is not a guaranteed scientific fix but it worked for me that time to clean up the dirty power whatever was going on. AC power can't be stored in capacitors. I can't find any description of HOW it works. |
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Post by svart on Jan 30, 2024 8:05:26 GMT -6
1: RFI isn't necessarily RF frequencies that are getting into your gear. At some point they need to be down-converted to audio frequencies to be, well, audible. Honestly there's a thousand ways this might happen. It could be happening IN the gear, or it could be happening in the wiring of the building. My best guess is that it's poor grounding with possible corrosion somewhere. Corrosion causes currents to flow through oxides which act like diodes and can end up creating a rudimentary mixer of sorts that mixes the line frequency with whatever the RF frequency is.. Again, it's possible but who knows if that's what's happening here. 2: Probably not. Power surges (fast enough not to be considered a brown out) would probably be filtered out through the power supplies, especially in the case of SMPS devices which are mostly isolated from input to output. Best guess is grounding, again. Unfortunately, if grounding is compromised, then nothing can fix the rest. 3: Not much can be done here unless you put everything on UPS units, but then you might start getting other types of noise since most UPS units are square wave outputs. "True Sine" or "Pure Sine" type outputs are available, but you'd need to make sure that you're buying a good one because a "Modified Sine" output will likely be comprised of smaller voltage steps. The other issue is that when it switches from AC to battery, it WILL likely pop and click as everything switches over. A computer doesn't care much but audio gear might. The vast majority of "power conditioners" are just fitted with RF filters and minimal surge protection. Using a "balanced power conditioner" usually just adds a large 1:1 transformer to isolate the Line and Neutral outputs from the input and float them so that the neutral is no longer tied to safety Ground directly. The large transformer will add a degree of filtering (acting like a large inductor). An "isolated power conditioner" will essentially be the same thing. Do you know of any machinery being used elsewhere in the building? Lots of machinery will use power-factoring to maintain performance, but it will cause a lot of noise on power lines and grounds when it starts and stops. Hilariousy the power went out in my house just after receiving this reply. You can't make this stuff up. This is good advice. I'm going to be testing the outlets for grounding issues as soon as I can grab a testing unit. But let's assume grounding is the problem as it very well could be. Would an "isolated power conditioner" improve that by isolating the ground? And in answer to your last question, the one good thing is that the building is only used for rehearsal spaces and usually nobody else is there when I'm there. So what's running is HVAC, lots of security cameras, a motion sensor on the front door (about 50' away), and a wifi router that's about 25' away. They don't isolate the ground. They isolate Line and Neutral only because Ground is there for safety. The funny thing about US wiring is that Neutral is what the current should return on, but we tie Neutral and Ground together at the breaker box, so they can technically have the same potential in some situations, even though they shouldn't. If you have a grounding issue, or a Neutral issue, currents can flow in strange ways and through things that shouldn't, like Ground between devices.. This is how you end up with ground loops, etc. |
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Post by mattbroiler on Jan 30, 2024 8:38:30 GMT -6
For more around the $1000 price you can get the Furman P 1800 PF R furmanpower.com/product/15a-prestige-power-conditioner-w-power-factor-technology/Sweetwater has it on sale for $750 at the moment and I got mine for $500 on ebay This one actually conditions the power rather than being a glorified power strip - it stores the incoming power in capacitor banks and doles it out in the proper levels. Another older model that has done similarly well for me is the Furman AR-1215 perhaps you can find some deals on ebay or REverb for these units Battery backup ups's a good idea for running computers and internet gear through but not amplifiers hell no. Another thing I discovered during our recent Oregon ice storm - at one point the house power/studio room developed some incredible noise despite running through the aforementioned Furman devices - loud hum crackling and seemingly compromised/bad grounding due to who knows what going on with the outside line coming into the house. Turning off all the music gear and shutting off that circuit breaker briefly then turning it back on cleared things up. I have a separate breaker circuit for the music room/computers so it is not shared with the house lighting and other stuff. This depends on whether you have access to the circuit breaker for your space and is not a guaranteed scientific fix but it worked for me that time to clean up the dirty power whatever was going on. AC power can't be stored in capacitors. I can't find any description of HOW it works. Ahh this is interesting. I defer to your expertise as I have absolutely none in these areas.
I only made that statement because I read somewhere that this is how it works but I don't remember now where I read that description. I assumed it was Furman describing the functioning of their own product which was that it takes in the power received from the wall socket stores it somehow and then sends it back out at the appropriate levels. There are separate power banks dedicated to amplifiers and sensitive electronics on this unit, plug your vintage guitar amps in here and computers there that kind of thing.
As I mentioned even this very fancy device that purports to "isolate" the bad quality incoming power from the power going out to your sensitive devices still fails to filter out external noise in some situations. Perhaps it has to do with the neutral/ground wiring you describe in the previous post? Most of the time it works very well and gives some measure of peace of mind for all of the expensive electronics in use.
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Post by gravesnumber9 on Jan 30, 2024 9:26:07 GMT -6
Another possible factor is that I'm running everything through an A&H GS3000. Since all sources go through that board, an issue with the outlet that the board is plugged into could be creating the impression of a system wide issue. Likewise an issue with that power supply (unlikely I would say but you never know) right? Problem is the pops are so intermittent that it's hard to even test for. We're talking like once every couple hours but its a total take ruiner so that's obviously way too much. Needs to be "never". Didn't get a chance to get out to Home Depot to buy the testing unit but I will today. EDIT: Here are the specs on that power supply for the GS3k www.soundpro.com/allen-heath-rps11-linear-power-supply/ |
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Post by doubledog on Jan 30, 2024 9:45:53 GMT -6
It could be anything at this point right? So start with the basics. Ensure wiring and ground tests appropriate (although with the $10 testers you can only get so far). But you may need to get an electrician in there to really sort things out. btw, for that fluorescent light, can you not just take the bulbs out on your side - then it will never turn on in your side.  |
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Post by gravesnumber9 on Jan 30, 2024 10:26:25 GMT -6
It could be anything at this point right? So start with the basics. Ensure wiring and ground tests appropriate (although with the $10 testers you can only get so far). But you may need to get an electrician in there to really sort things out. btw, for that fluorescent light, can you not just take the bulbs out on your side - then it will never turn on in your side. It never gets turned on but... yes I should probably do that anyway. |
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Post by jmoose on Jan 30, 2024 18:55:25 GMT -6
Very, very interesting. I know for a fact that all there are outlets on the circuit not in our room. Well not for a fact, but I'm pretty sure. Because when the light to the storage closet goes on, it also flips a (you guessed it) horrid fluorescent light on in our room. Now, that rarely happens when I'm in there, but I have no idea what else is plugged in in that room. I will check that out for sure. If the circuits in your room are shared with other rooms in the building there's really not much of anything you can do. Move out? At that point the only real solution is going to be a complete rewiring and have your own dedicated panel installed, which as a renter isn't happening? Too big an investment. About two decades ago, the first real incarnation of the moose shop was behind Giants stadium in an old turn of the last century warehouse the size of a city block. My little corner of the building had a dedicated panel that was shared with a couple other rooms... for the most part it wasn't really a problem. But once in a while there were things... Like a freight elevator on the other side of the building that despite having an Equi Tech balanced power box... would STILL inject a massive hum into every single piece of gear in the room. If and when someone was using the freight elevator it was game over. Zero recording until they're done. As a few have said the $100 furman boxes don't really do much of anything. They're going to filter out some line noise (mini fridge turning on & off) and really, if something goes totally wrong take the sacrificial hit without affecting other gear but that's about all they do. The real power conditioners cost thousands and are insanely heavy. You can't lift them with one hand like a furman. And they still can't fix problems that come from bad/shared wiring... like the freight elevator with our neutrals tied together where juice comes in from the street. Nothing fixes that. And keep in mind as you examine outlets all the basic tester does is show if they're wired correctly or not. If the ground is dirty and contaminated from other stuff in or even outside of the building? Backfeeding voltage into your place? That crucial bit of information will not be revealed... |
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Post by gravesnumber9 on Jan 31, 2024 1:35:13 GMT -6
So... no issues at the outlets, at least not faulty wiring ones. The voltage was a little hot though, steady at 125 or 126 in every reading.
All kinds of stuff plugged in to a shared circuit in the broom closet. A modem, a couple routers, a clock.
I've got a medical power conditioner with a toroidal transformer coming in that I just picked up off of eBay. It's only 5amps but I can run the key stuff through that and a few lower end power conditioners and we'll see.
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Post by gravesnumber9 on Feb 13, 2024 17:08:16 GMT -6
Ok, so I've got an update here!
I purchased a medical grade power block with a toroidal transformer on eBay for like $150. It was originally used for some sort of imaging machines and weighs about 10 or 15 lbs. It's heavy.
I also did some basic power routing management and moved all the "dirty" stuff off the circuit that has my outboard gear on it. So my console and all of the outboard is going through the big transformer while the lights, amps, fridge, and printer are going through different circuits. I thought I had already done this but it turned out a few items had slipped through the cracks when I was moving in. "Temporary" placement that I forgot was supposed to be temporary. Classic.
The challenge here is that the issue is infrequent enough that it's hard to to trouble shoot because I can't "cause" the pops on command. But, I've had enough of a reasonable sample size now (three sessions of 4 hours each) with zero issues that I'm either on an unprecedented lucky streak or the problem has been solved.
Thanks for the suggestions both on this thread and in the PM's. In the end I think we whooped this by a combination of smarter cabling, a $15 tool, and a $150 ebay purchase. Not bad.
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Post by sirthought on Feb 15, 2024 3:23:18 GMT -6
Which device did you purchase?
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Post by brenta on Feb 15, 2024 7:35:18 GMT -6
This is what I was going to suggest. Tripp-Lite makes “hospital grade” isolation transformers that are a lot less expensive than studio power conditioners that have isolation transformers. Sounds like you got one of those or similar.
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Post by gravesnumber9 on Feb 15, 2024 8:21:49 GMT -6
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