how do i identify ground loop hum ?
dose the hum come and go or slowly pulsate ?
and where do you hear it from ? (speakers/amp)

i have a slow hum that comes and goes (1-3 times a minute)(creeps in and out) and it comes from the amp not the speakers ...... is this ground loop hum ?

HELP
Supertom

Supertom...is the hum coming directly from the amplifier itself? Does the unit continue to hum if you remove all input and output cables from the amp? (Please do this with the power OFF!)

My friend's computer makes noises very similar to your amp. In her case it's a bad power supply fan. If there's no fan in your amp...and the hum is indeed coming from inside the amplifier itself...the problem may be a loose lamination or winding on the power transformer.

Ground loop hum is something you would hear coming from the speakers.

BobZoom

As BobZoom says, ground loop is generally produced by the speakers. It's also more commonly a continuous sound. It is possible for ground loops to produce hum in an amplifier itself (there have been cases reported of this happening with Model 200 and Model 2200 amps ). There are no fans in the Model 7500, so this noise is most likely coming from the transformer. If it's pulsing, I'd suspect something like a compressor or other piece of equipment elsewhere in the house producing the problem (similar to the hum that can be produced by dimmers). The best place to start may be to go through the standard ground loop search (disconnect everything in the system and slowly add each connection back, checking after each one to see if the hum is tied to that connection), although I'd start by simply unhooking everything from the amp except for power. If the hum is present when just power is connected, I'd try connecting it to a different outlet, then try looking around the house for possible noise generators (unplug the fridge, turn off the AC, turn off lights).

I had the same issue when I hooked up my 7700. Seemed like it was a hum that came and went from the Amp. I tried unhooking everyhting and it was still there. I added a Panamax stage 4 power conditioner and it went away. Been perfect ever since.

Hello Tom,

What you are describing sounds like mechanical hum from the transformer which is usually caused by something external to the amp, it's rare to have a faulty transformer. It's something we never see with these amps.

Use a heavy extension cord to plug the amp into several different circuits throughout your home. You should eventually come across an outlet where it no longer hums. If the problem ceases to exist with another outlet then there is most likely too much current draw. A textbook symptom of inadequate power with an amp using a toriodal transformer is that it will hum from the chassis if there is a voltage sag. Sometimes it's not the voltage, it's DC offset voltage across the AC line. Unfortunately this is tough to pinpoint, the only way to verify whether it's the amp or environment is to physically move the amp to another location. Obviously this is the last course of troubleshooting but it's sometimes necessary. It's probably nothing to worry about and you should be able to pinpoint the problem using the extension cord tecnique. It could be something as simple as a halogen lamp on the same circuit. During troubleshooting try to think of anything sharing an outlet in that room however benign you may think it is, dimmer switches, heater, any appliance, etc. I should add that we've had a few amps sent in for mechanical hum and to the best of my knowledge none have exhibited hum in our test environment. Please be syre to contact me if you have any questions or need to troubleshoot further.

HELLO STEVE:

After using the above extension cord tecnique i found the hum went away.
So i think ill just add a seperate 20 amp circuit just for the amp .... it worked but only if thats
all that was connected into that Plug as soon as i add ANYTHING Else (EX:990) the Hum would return
so i just run it (AMP) without sharing the outlet .... so far so good

Now just the other day while listening to music (not that it matters but low volume) and working around the house my wife turns on the hair dryer in the bath room and slowly the sound disappears
and the HUM returns (turning the hair dryer off everything returns to noraml)

Is that AMP drawing that much current that i can't run it in MY HOUSE ??? (I really don't want to return it) but i'am a little confused about what i should do and what my options are

am i right to say that if the ONLY thing running in my home is the 990 and 7500 and CD player that i SHOULD not have any problems because there the only things using Current ?

Hair dryers, vacuums, and refrigerator compressors are all significant electrical loads that can do odd things to your house power. If the bathroom circuit is related to the amp's circuit (same leg of the house service, for example) then there could be some weird interaction. Do you have any sort of power conditioner? Something like that (such as a Belkin PureAv PF30 or PureAV PF40 ) could help cope with the noise/trash being dumped onto the house wiring by devices like the hair dryer.

hey GONK i have connected to all other equipment on a separate plug a Monster Cable HTS850 but not the amp .... the amp is on its own 20a circuit
and its own plug if i plug all my A/V + AMP into HTS850 and then into my new 20a circuit i get the HUM again (is this really a case of not enough power in my house ???) can i test something ?
PS:never had anything like this with my last System Yamaha/Cinpro which i just sold

anyway thanks for your HELP
SUpertom

You could try putting the amp on the HTS850 by itself and connecting to the dedicated circuit, then run the hair dryer to see what happens. It wouldn't cost you anything but time.

My old house (roughly 1000 square feet, built in 1954) originally had only a 60A electrical service. When I set out to install a stacked washer/dryer a few months after I moved in (the existing dryer was in a closet on the back porch), I needed a new 208V outlet. There was no way to add the new circuit with the existing service, so I had it yanked down and a 200A service installed. If you've recently had an extra 20A circuit installed, I suspect that you are not in the same position that I was then, but you could ask the electrician who put it in what size the existing service is.

Hum usually isn't caused by a lack of power! It is caused by other things, ground loops, etc.
It sounds to me when you plug your amp into the extension cord you are putting it on a separate phase, (most houses have 2 phases of 120 volts apiece), than your other equipment. When the electrician installs the new outlet make sure he keeps the new outlet on the same phase as the extensiojn cord. Jim

Hullguy,

I've experienced similar problems with my Anthem Statement amplifier, but I've not been able to isolate the problem. All I know is that the degree of hum is not consistent. I've yet to try the extension chord method.

This house was built in 61, with a 60amp service, but was updated to a 100 amp, in 85. Most of the breakers are on the upper rail. When you say that Supertom should be sure to have the new outlet installed on the same phase as the extension chord outlet, what exactly do you mean?

Also, my amp doesn't have a ground lead, but has a binding post for grounding. I grounded the amp to the grounding post in the main box. However, given that when there's a problem, the excess load is dumped to ground, I'm thinking this could actually harm my amp and have reconsidered grounding it to a nearby water pipe. Is this a good idea?

Any and all information, appreciated.

thanks,

John

When the electricity comes into the house it enters on 3 wires. 2 of these wires are hot and typically attach to bus in the electric panel. One hot wire goes on the right bus and the other wire goes on the left bus. Each one of these bus is considered a phase, (the AC sine wave is out of "phase" between each bus or wire). The circuit breakers plug into this bus giving you your individual circuits. The way these bus are laid out in the panel causes every other circuit breaker to be a different phase.

The ground wire in a house is generated by running a wire to ground rod. In the old days you just used to attach the ground wire to the cold water pipe. You are still supposed to ground any metal systems, like plumbing, in a house. So, if you attached the ground from your amp to the water pipe, electrically, you have attached the wire to the same point as the ground in the panel. I think the way you have it is fine, as long as any humming isn't created or intensified.

The ground wire is designed to carry large fault currents. This is how a circuit breaker works. A large amount of current flows through the ground, in a fault situation, causing a sharp increase in heat. This heat bends a bimetal latch releasing the switch in the breaker.

I hope I wasn't too long winded and didn't leave anything out. If I didn't do a good job of explaining this feel free to ask more questions! Jim

Jim,

I think I understand. Just to be clear, though; if I have two circuit breakers installed, adjacent to each other, then, this pair is out of phase with each other, so that if I were to install a third, the outside pair would be in phase?

In my situation, the majority of breakers are on the top row, while the bottom row is nearly empty. Installing a new breaker on the bottom row, then, doesn't insulate or isolate it, in any way, from the breakers on the top row; correct?

It is as you say, with the three main wires coming into the house. Is there a way to create a separate circuit from the main box, entirely, so as to isolate the home audio equipment from every other electrical appliance in the house; or, is it just not possible to separate the two?

Jim, not long winded at all. I appreciate the response!

Thanks,

John

I'll leave hullguy to get the better answer to these questions, but typically the panelboard schedules I see at work alternate between the two (or three, in commercial work) phases - so the ones all at the top will still be spread across both phases.

The circuit breakers alternate phases from top to bottom. Each panel is numbered, starting from the top left at 1. All the circuits on the left side are odd numbers, the right side even. So breaker number 1 and breaker number 2 are on different phases.
Breaker number 1 and breaker number 3, are on opposite phases. Breaker 3 and 2 are on the same phase. The phasing zig zags through the panel,ie.circuits 1,4,5,8,9,12,13,16,17,and 20 are on the same phase. 2,3,6,7,10,11,14,15,18,19 are on the other phase. This makes it easier to keep the loads balanced.

You can add a panel dedicated to just your audio equipment. To really isolate it from the other power in your house you would need to install a 240volt to 120volt/240volt isolating transformer with batteries. Now you have a UPS system for your stereo!

An easier way is to buy a single circuit UPS,like this,
http://www.tripplite.com/products/product.cfm?productID=2721
Hope this explanation helps! Jim

Jim,

Thank you for the excellent explanation. I'm just about to print it out, for personal reference.

I've never heard of a UPS; what is it? I've read through the tripplite specs and there's nothing mentioned about EMI/RFI filtering, which, I assume, is what some of these other power conditioners do. Is this a valuable feature to have, or is it unnecessary with a UPS? Can I achieve a UPS configuration with any of the items listed on this page:

http://www.surgex.com/products.html

which also include EMI/RFI filtering?

Jim, thanks for your help!

John

A UPS is an "Uninterruptible Power Supply" It simply means that you will not lose power to whatever is plugged in until the batteries die. If the power comes back on before then, you will never see the power go out.

These are really good surge protectors (used by professional AV contractos), but none of them appear to be UPS's. They are surge protectors, meaning that they are intended to filter "noise" (electrical hums from other household loads: fridge, hair dryer, COMPUTERS) and protect from "spikes"
All this means is that it helps protect your sensitive electronics from getting potentially damaging over and under supplies of power along with helping filter out other unwanted signals in the power.
Believe it or not, while all of these normal culprits (washer, dryer, fridge, etc) do cause wierd effects on house power, computers and other digital electronic devices add tremendous amounts of "noise" to your home power.
Some reasonalble explanations for "Hum" often have to do with an insufficient ground of your whole system.

This is not a huge problem. It means that your things will still work, and is safe, but it also means that all the "nasties" getting fed back into your household power are hanging around instead of being escorted into the ground.

Most UPS systems take the power from the house convert it to DC feed it through the batteries and then convert5 it back to AC. Because of the UPS doing what it does, the DC conversion, it should eliminate any noise injected on the power side! It also acts as a surge protector!

taylodr and Hullguy,

thank you for the responses and explanations. A UPS would be most useful for my computer, if I were employed to engage with it. Otherwise, if there's a power outage, I have candles! In other words, I wouldn't be concerned about backup.

My main interest is only in eliminating hum, from my toroidal transformers (now I'm wondering if my plasma is also affected). The 20amp SurgeX surge protector has also the noise filtering, but for about half the price of the Tripp UPS.

Given my circumstances and needs, how would you advise? Would the 20amp SurgeX suffice or would the UPS condition the power more effectively? And, how would something like a Shunyata Hydra 6 compare, or is this more hype than an effective solution to a transformer hum problem?

Also, as I explained, this house was built in 61, the service upgraded in 85 to 100amps. The house was built with three wire, with a ground wire, but only the boxes were grounded as the sockets were without the ground receptacle. So, when I purchased the house, two years ago, I installed all new receptacles and grounded each, the boxes and sockets. The main power box is grounded to a rod that's driven into the ground at the other end of the house, connected with a heavy, braided, copper cable.

Any and all info, appreciated.

thanks,

John

I would say try the cheapest solution first, making sure you can return it. I might ruffle a few feathers, but I personally don't see what a lot of these "high end" power filters do. (I do understand that people who have the money to spend that can "hear" the difference - real or immagined - that is great, I am all for everyone being happy with their own system.) The surgeX devices are designed to help filter that exact type of hum.

taylodr,

that's what I'm interested in, filtering toroidal hum, primarily. Whether there's a qualitative improvement in sound is a secondary concern.

So, you think the SurgeX attempt is the way to go, then? I know the AV installers rave about these things.

There's a music shop, here in town, that's willing to order one in for me. I'll ask about the return policy.

thanks,

John

I had the same issue in my last apartment (toroidal hum/buzz). I added a Panamax line conditioner but it did not help. From what I researched it was most likely caused by other electronics bleeding over DC onto the lines making them dirty. This DC makes the transformers in amps go crazy. Some amps have more tightly wound (and glued) wiring in their transformers and exhibit the buzz less often. For what it is worth, I unplugged everything in my apartment and even flipped off all unused breakers, but still had the hum/buzz. My only conclusion was that the apartment complex in general had dirty lines. Of course, I'm no electrician, so who knows I just knew I'd be moving eventually so I dealt with it.
I have since moved and no longer have toroidal hum
For what it's worth, PS Audio claims to have a product that'll remove all DC from your lines.
http://www.psaudio.com/products/humbusterac.asp
I neither promote nor discourage this product as I haven't used it. I have no idea if it would solve your problem. But, I just thought you might enjoy the reading.
Sorry to put even more options out there

jrlouie,

please, no appologies! Any and all information is helpful. And, actually, this is the cheapest approach, so far!

I will look into it, further. The hum, late at night, destroys the joy of hifi audio!

Thanks, JR!

John

You know, I just had a thought. The other appliance thing got to me. Check your panel again. Make sure that 1. your neutral bar is properly connected to your ground bar and 2. your ground is sufficient.

I am really beginning to think that you have a poor ground, and you are building up excess niose on your neutral. It is possible that your ground is not great, and you may help by creating an additional ground.

taylodr,

I'm obviously no electrician, but, can I check the ground by using an ohmmeter to check resistance between the ground in the main panel and, say, the ground of my nearby water pipe?

thanks,

John

taylodr,

I checked and you're right, the incoming ground wire/cable, the copper water pipe and the main panel's ground, all show zero resistance when I check between them.

How do I check if my neutral bar is properly connected to my ground bar?

Some of the ground wires seem precariously attached to the main panel’s ground bar. I'll have a better look in a minute.

One other thing, at the bottom of the panel, there's a transformer and I'm pretty sure it's for the doorbell system, of the house. It makes a constant buzzing noise ... 24/7. Does this mean anything, is it helpful, in any way?

thanks,

John

I've taken a closer look and it appears that the electrician that changed out the panel, in 1985, took the ground wires from the various lines in, twisted them into one connection, with a marr connector and grounded three or four lines in, with one ground wire.

Also, my amplifier does not have a ground prong, just a post on the back which allows you to ground it, if you so wish, which I have done.

Thank you all for this,

John

Bump ...

what, did I scare everyone away?

John

Have you tried connecting them individually to the ground / neutral bar? Or a better question, how is your dedicated circuit grounded? Strait to the g / n bar, or tied in with the other stuff?

I haven't tried connecting the ground wires, of the lines in, directly to the ground/neutral bar because the lines in are all too short (the reason, I assume, the electrician did it the way he did).

I have a ground wire from the ground post of my amp, directly connected to the ground/neutral bar in the panel.

That buzzing door bell transformer shares power with the line, I think, for my audio room. Can this transformer cause dc on the ac line? This is absolutely new to me, these concepts.

thanks,

John

DR_JB,

I read through the thread and a couple of things pop out:

You definitely need to determine if you have an adequate ground.

Also, the benefits of the UPS have not been clearly articulated. The PRIMARY reason to have a UPS on your audio/video system is to take whatever voltage that comes in and output it as a pure 120VAC sine wave. This gives your more available voltage because 120v it the RMS (essentially average) voltage. The actual peak to peak voltage is quite a bit higher. It can take in voltages as low as 86 volts and as high as 137 or so volts, again, outputting it as 120VAC. It also cleans out all line noise and spikes. It has really nothing to do with the issue of when the power goes out other than it protects your gear from the on/off/on/off etc as the power company tries to stablize power in an outage situation.

I have to tell you, I have 2 UPS' in my system. A 1500VA (900 watts) and a 3000VA (2200 watts). The big boy feeds my Outlaw 7125 and my Carver M1.0T. The other one feeds my Adcom GFA555 and the rest of the gear.

I have seen many benefits to having the UPS' in my rack. The first and foremost is it has added unbelievable punch to the low end in my system. My Adcom is in bridged mode (600watts) and drives two 12" subs. So I already had tremendous furniture vibrating low end. But when I hooked the amp up to the UPS, now I can feel the impact in my chest even at lower levels. The reason for this is again, more volts available to the amp because of the pure sine wave. Also, it tends to give you more available reserve for the amp to pull power from. Awesome power. The next benefit was a dramatic increase in imaging. For my mains I have the Martin Logan Aeon electrostactics that already have incredible imaging. But when I hooked the Carver amp and the rest of the gear up to the UPS, HOLY COW! The imaging was rock solid. Better depth. Better width. Increased resolution of the sonic field. WOW. The last benefit I noticed was on my Hitachi rear screen HDTV. The picture has less noise, deeper blacks. I was actually suprised to see the difference.

Everyone who spends the kind of money we do on gear should have one or more of these in their racks. Let me tell you this. Do NOT spend $2K on the high end Monster or similar units. Buy a reconditioned APC or similar rack mount unit that they sell for computer server rooms. You can get them in 120V or 208/240V units that will more than feed everything you need. The 1500VA unit is actually a CyberPower that I paid $200 for. The 3000VA is an APC that I paid $440.

Next to speakers, I would have to say that this is one of the best improvements I have heard in my system. I have tried high end speaker wire and interconnects which helped, but not as much as the UPS.

Good Luck.

Sorry, I was sidetracked! The UPS I linked to was for informational purposes only. I'm sure you can find a less expensive unit.

AudioGuru66 is correct in what he says about what a UPS does. In audio you would be using it as a way to provide a clean, pure sine wave. It would clean any extraneous noise induced before the UPS. I'm not concerned about keeping the audio system running for just 5 minutes after power loss.

The transformer you are talking could be the culprit! It shouldn't be making the sound your saying it is. It might be time for a replacement. They are inexpensive and can be bought at Home Depot, or any hardware store. Shut the circuit breaker off and remove the wire feeding the transformer and see if this works.

That's exactly what the electrician did to the ground wires! So long as the connector is tight and the wires don't easily pull out of it, it should be fine.

As I'm typing a thought came into my head. In most panel installations in houses the grounds and the neutrals,(white wire), land on the same bus. This bus is supposed to have a green screw driven through it into the circuit breaker cabinet. If the ground wires are separate from the neutrals, then either the same screw is used or a wire jumping between the 2 connection points is required. The neutral and the ground in a panel MUST be attached!!!

If you take your meter and check the resistance between the neutral and ground it should read "0"
Hope this helps. Jim

P.S. Be careful in the panel!!!!

AudioGuru66,

Thanks for the advice. Tomorrow, I will work through the power panel and check for all these weaknesses, including the ground and buzzing transformer.

And, thank you for the detailed explanation, regarding the use of a UPS. These things are quite the machines, weighing in at 50/60 lbs. You are right, I did not understand.

Is this the type of UPS that you have:

http://cgi.ebay.ca/APC-Smart-UPS-3000-Ra...1QQcmdZViewItem

and, if so, what do you think of this one?

Hullguy,

No need to apologize; I understand we all need to live our lives. I do appreciate your guidance, however. Tomorrow I will work through the power panel and check for all the points you've made reference to.

I need also to distinguish the individual circuits, given that last night, when I turned on the amp, all the lights in the kitchen dimmed (which is not good, as I thought it was a separate circuit). My kitchen has two new dimmer switches, Divas, and, the electric stove, the motor/compressor in the fridge (not the best circuit for my amp).

I'm going to pull the transformer for the doorbell and see if it makes a difference and, I will also replace it, purchase another, next time I'm at Home Depot.

Thanks for the detailed explanation. I will be careful, will use latex gloves.

That APC 3000v unit seems about right, as when I added all my av components together, it worked out to 30amps. But, gee, this ebay APC unit is huge, bigger than my 1900 watt amplifier! I think it weighs nearly 60 lbs.

The other worry is that while I'm looking to achieve clean power for my AV equipment and eliminate toroidal hum (primarily because it bugs me), the APC could be counter productive as I understand it has two 5", internal computer fans! Gee, I could end up with more, rather than less, noise! lol Am I right about this?

I certainly appreciate your guidance & thank you!

Sincerely,

John

P.s. ... it's nice to be learning new stuff.

Here are the specs for the unit:

http://www.apcc.com/resource/include/techspec_index.cfm?base_sku=SU3000RMJ3U

Is this a good one?

I was wrong about the weight, it's not 60lbs, it's 75lbs and that's without the batteries.

The specs say:

Audible noise at 1 meter from surface of unit 47 dBA

I don't know how to measure the noise of my toroidal hum, but I'm guessing it's less than this.

John

Dimmer switches are known to be "dirty" in reqards to induced noise on circuits.

If you can place the ups in a remote location, in the cellar or attic, the noise from the fans becomes a non-issue. I placed all of my amps in the cellar.
This APC unit seems fine, it provides plenty of power. Jim

hello ALL

I want to buy one of those UPS thingy's (hahaha)
but not sure what to look for
mostly i like the regulated power and am not to concerned with having short term power when the power goes out
do i just add the wattage of my equipment and buy like that ????

THANKS AGAIN
Supertom

Hullguy,

having this UPS in the basement would make the installation far more complex, as an oak covered floor would divide the system from the power source. A single power cable I can get through the floor, but not several speaker wires, or several power cables.

That thing is monsterous in size ... 25" deep and 70lbs, without the batteries. My room is not big and this will add more noise. It may be ideal for some, but not, I think, for my circumstances.

In terms of a practical application, I think the Surge-X is probably the way to go. I'll include an AV installers opinion on all this, in the next message.

thanks!

John

John,

Yes, UPS systems do clean up the power very well when converting AC to DC then back again, but again most filtration systems on good surge/spike protection system will do the same thing, except that the UPS is louder (as you noted).

In regards to providing a constant 120VAC to an amplifier, this would be a valid point if the amplifier used a regulated power supply that is fixed @ 120VAC. However, almost all power supplies for amplifiers use transformers that have multiple taps on them that will draw current based upon what the incoming voltage is (usually between 100VAC & 125VAC).

The problem with hooking up a good amplifier to a UPS is that unless the UPS is capable of allowing sufficient current draw through it (in large bursts), the amplifier will react just like it does without a UPS. Remember, these UPS systems are not car batteries nor do they have capacitors to allow quick discharges of large current without effecting other systems.

Also, most high capacity UPS systems don’t have great surge/spike protection. The APC 3000VAC unit has good, but not great protection and is not impervious to lightning.

In the end, unless your voltage is down around 100 to 107 volts ac, then I would stick with an item like the Surge-X.

There are other items to discuss in regards to the above, but on a side note I have a friend who designs amplifiers for a major electronics company and his golden rule is to always allow amplifiers to run with as little resistance between them and the power grid, placing a UPS in between the two is just not something he would ever do (and he has tested this with bench equpment).

Feel free to ask any other questions if you like.

Regards,

I am unsure why adding a UPS between an amp and the power grid would add any resistance. That sounds a little far fetched. I'll put it another way: the positive clearly audible effects a UPS has on audio quality are undeniable. How it affects your amp electrically, while measurable as far as impedance or resistance goes, won't hurt your amps.

I would like to add is that yes, the particular large UPS I have is not for everyone. The smaller CyberPower can be gotten as large as 2000 or 2200 VA. It does have a fan but the fan only runs when there is no or too low AC input.

To answer one of the questions by one of the other posters about sizing a UPS for your system, it's pretty straight forward. In the AC voltage world, watts*1.67=VoltAmps(VA). In DC, watts=Volts*Amps. But because AC voltage is a sine wave whose nominal amplitude is represented as RMS Volts you have to use the power factor conversion to go from watts to VA. So to size a UPS for your application you add up all the watts that all your components draw, multiply by 1.67 which gives you VA and pick the appropriate UPS. If want to use smaller multiple UPS units, just make sure your total load does not exceed the max load for the UPS. Most UPS units also tell you what the equivalent watts are so you don't have to calculate it necessarily.

In my case I have a 3000VA unit and a 1500VA unit. That's 2200 and 900 watts respectively. The Outlaw 7125 draws 1440 max so it is too much for the smaller unit IF I am driving all 7. In my case I am only using 5 so it can be on the smaller unit. That's 1029 watts but it's all for surrounds and center. So more than likely I won't be using all of that. My Adcom amp for my subs draws 1000W at full power. Since that is bass it can and more than likely will draw all of that. The Carver amp draws 1000W at full power. It drives my electrostatics so I will probably use all of that too. So I have the 7125 on the smaller unit and everything else on the big one.

Bottom line is that is works great. It sounds awesome. What more could I ask for?

Volt/Amps are Volt/Amps whether on the line side of an UPS or the load side!!! The UPS shouldn't have any effect on the amps hunger for electricity.

An easier way to size a UPS for the home is a 15 amp circuit provides 1800 VA. A 20 amp circuit provides 2400 VA.

In a single phase circuit VA=Watts.
http://www.angelfire.com/pa/baconbacon/page2.html

Adding the UPS to the circuit in the cellar is easier than you would think if you are positive which wire feeds the outlets feeding the stereo.

I ca explain it if you'd like me 2.

Hullguy,

I'd certainly be interested in an explanation.

I checked the power panel and everything is grounded as it should be, all the screws are tight and there are two ground cables that come into the power panel (the one is attached to a rod, driven into the ground, at the other end of the house. Where the other ground cable comes from, I can't tell.

I removed the doorbell transformer from the circuit and no more buzz in the panel. Also, I don't know if it's my imagination, but from my seating area, I can no longer hear my amp.

However, when the compressor was running in my fridge, my amp seemed louder and when it turned off, it was quieter, within the moment! Is this actually possible? Or, is it just my imagination?

Sorry, didn't mean to veer off topic.

I did the math; if I add all my AV components together, max draw is 3,000 watts. I can't imagine coming even close to this kind of draw, however and so how should I judge my requirements? Should I just shoot for the 3,000 watts, which I thought was 30amps?

I like the idea of the UPS, but the professional AV installer insists that the Surge-X is the` thing to have, the way to go. The pricing is comparable. Also, that 70lb UPS is just not happening in my small living room, with two, continuously running, 5” computer fans. If I could keep it in the basement, safely and interconnect, that might be an option, but I can’t see how, without making a lot of holes.

Again, I appreciate the input from everyone here; I thank you all. I’m enjoying this, also, always love to learn new things.

John

I'd throw the circuit off feeding the stereo and see if the fridge light goes out. If it stays on, it's on a different circuit, but it's causing voltage drop! I'd try to move the stereo circuit on to the other phase from the fridge and hope for the best! BTW the UPS would take care of this VD.

DR_JB you've got to go with what you feel is best in this situation. I'm a Master Electrician who likes good AV equipment, not a Pro AV guy. He has more resources and deals with this kind of thing more often than I do.
If this works, maybe your guy can come to the TD Banknorth Garden and figure out where our data noise on our headset circuit is coming from!
Jim

Jim,

You’ve been really helpful, as I'm certainly not a Master Electrician and would be lost without your guidance.

I'm going to check out the circuits, tomorrow. I’ve been a bit lazy about it because I don’t like having to reset the clocks.

I'd like to have a dedicated circuit, for the AV system, alone and at least 20 amps.

I'm still somewhat unsure. In time, I'll make a decision and in the mean time, I'll keep at the panel. I need to buy a new doorbell transformer and one of the push buttons are also broken, need replacement.

I figure you’re kidding, but if you really want this person’s advice, I’d be more than happy to put you in touch with him!

Thanks,

John

Jim,

I turned on all the lights and appliances and one by one, turned off a breaker and looked for the effect. Here's what I discovered.

My main panel is a 125 amps and its length is horizontal, with the main switch on the right, breakers on the left. Most of the breakers are on the top row. The breaker closest to the main switch, on the top row, is for the fridge and microwave. The very next breaker, adjacent and to the left, away from the main switch, is the breaker for the audio circuit. The lights for the kitchen are on, yet, another circuit, to the left of the audio breaker.

Also, the panel has two ground cables and everything is as tight as can be.

So, I'm not sure why, then, but when I turn on the amp, the lights in the kitchen will dim, momentarily.

Once I choose surge protection/power conditioning, I'd like to build a dedicated circuit. I'd actually like to take a picture of the panel and send it to you or place it on here, so you can further guide me.

Can the draw from the amp, initially, be that great that it affects all the circuits?

Since I removed the buzzing doorbell transformer, the amp does seem quieter. I had it on for several hours, yesterday and before I went to bed, in the quiet of the night, the difference was noticeable. So, this is good.

Again, thanks!

John

Strange Panel layout! Not that it affects the electricity. Who is the manufacturer of the panel?

When you shut the audio breaker off did anything else go off? If nothing else went off, you already have a dedicated circuit.

The lights dimming when you turn the amp on is caused by a voltage drop. When anything is turned on, typically, is when largest amount of electricity is used. Do the lights dim when the refrigerator starts? The light circuit and the fridge circuit are on the same phase, while the audio circuit is on the "other" phase.

Take your meter and set it to voltage. Check the voltage between the two main feeds. Then check the voltage from each one of the feeds to ground. Then check the voltage from each one of the feeds to the neutral,(this should be the same reading as the feed to ground).

I'll PM you with my e-mail address for the photos. Jim

I forgot to add the surge suppression alone won't take care of the lights dimming. Jim

Jim,

the panel is manufactured by Sylvannia.

No, the amp seems to be on a dedicated circuit, as you suggest. The house is well divided, with lights and sockets on separate breakers.

The fridge and microwave have their own breaker, separate from the lights in the kitchen.

I'm not so concerned about the lights dimming, if what you're saying is that the voltage drop, as I turn on the amp, is across the board and normal?

I've never noticed the lights dimming when the refrigerator starts, only when the amp turns on, initially and momentarily.

I'll get a pic, this afternoon and send it along. And, I'll do as you advise.

thanks, Jim!

John

Can you hum a few bars for us? You never know, sometimes if you change the tune it helps.

What you describe about the lights dimming when you turn the amp on, at least in a residential setting, is actually fairly common. A large amp with the large transformer and capacitors will draw a very large amount of current albeit for a few milliseconds. That causes a voltage drop. I have a 200 amp service in my house and before I hooked the unit to either of my UPS units, the lights would dim for a brief moment. I also noticed that if I push the system really hard the lights would flicker just a little. The two ups devices fixed that. It was worth every dime.

I can't stress enough how much clean power has cleaned up the imaging and added punch to the low end. I do have some very light fan noise but the fan from the big unit is only on for a few minutes at a time. The fan for the little unit are on only when the input power is off.

AudioGuru66,

thanks for the info. Yes, it's as you describe, the light dims for only a fraction of a second.

If that UPS unit wasn't so monstrous, I'd seriously consider it; but, at 70lbs (without batteries) and 25" deep, it just seems too impractical.

I'll figure this out, sooner, hopefully, than later.

thanks for the response.

John