How to know what kind of circuit you might need to power your equipment?

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Robert D

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Thinking about what I might run into if I replace my subwoofer I have now with a more powerful one. I now have my home theater just set up in the family room. Right now I am using a ML Depth i. Just one. I also am running my Aragon dual channel amp (200 watts at 8 ohms each channel), my Marantz receiver that is 11 channel, the tv, bluray, sonos, 2 Prodigy speakers, cable box, and God knows what else on it. Right now the circuit seems fine.

Wondering about that regular 15 amp circuit. Im pretty sure the whole room is just running off of one 15 amp circuit. Looking at the breaker box I see what looks like just one breaker.

The Depth i I am using now is only 350 watts. What if I went to the Balanced force 212 which is 1700 watts https://www.martinlogan.com/en/product/balancedforce-212 , or maybe this Monolith M 215 that is 2000 watts Monolith by Monoprice M-215 Dual 15" THX Ultra Certified 2000-Watt Powered Subwoofer - Monoprice.com

I wonder if just that one circuit would be safe and/ or not trip. Ive got multiple power outlets on the wall by the home theater setup, but of course those are all in the same circuit since they are in the same room id assume? I had the house built but at the time I didnt consider such things, wish I had. I dont want to think about the trouble and expense it would take to run a new 20 amp outlet up to that room. The breaker box is of course in the basement and half of the basement is finished, so running the wire would be terribly difficult without tearing up drywall I think.

I know there is a formula Voltage x Current = Watts. So a 15 amp circuit should handle up to 1800 watts. Is it as simple as looking at the RMS wattage of the amplifier on the subwoofer? The monolith is 2000 watts RMS but 3600 peak. Is it a simple 1:1 ratio of the rated power of the amp to watts supplied by the circuit? Going by that then the sub wouldnt be safe to run just by itself on a single 15 amp circuit. I see on the website that people are indeed running it on those circuits just fine. I would guess that those people have other things running of that circuit as well, like me. It just sounds a bit risky. Trying to figure out what will be the case before I buy something.
 
Robert,

That's why I use a 30A breaker to supply the energy to my room, and also have a 20A balanced AC Line Conditioner (BPT Singnature 3.5 Plus). I do not play my system too loud, but if I want to be a show off of its power, I cranked up for some time, having only crystal clear sound, even that it is evident the I am playing the system very loud.

My system with this Power Line Conditioner, does not compress the sound at all. I also have a separated copper welding rod for my AC circuit. Costa Rican energy is not too clean, so using a balanced line conditioner solved my problem: clean AC to power my system.

Our Mains AC line is same as yours, 120 V.AC. Our wall socket is the same, one hot 120V line, one neutral and ground. The balanced line conditioner uses 2 hot lines and the center is ground. This unit has a big toroidal transformer, the unit weights about 80 pounds, and here is the wiring:

1599567853908.png

There are other Balanced AC Line Conditioners that offers about the same 20A. It is wise to have more energy reserved of the total power consumption of the system.

When I use this BPT for the first time, my ears were so happy, that I was rediscovering all my music.

Happy listening!
 
Robert D, you can easily have an electrician run a second line to where you plug in your gear. This would give you a 20 amp line on top of your current 15 amp line. It would have its own breaker and wall plug. It would look professional too. Then you can just plug different gear into whichever plug you want. At the audiophile level you are talking about a second line is really an easy permanent fix. I say go for it!
 
Robert D, you can easily have an electrician run a second line to where you plug in your gear. This would give you a 20 amp line on top of your current 15 amp line. It would have its own breaker and wall plug. It would look professional too. Then you can just plug different gear into whichever plug you want. At the audiophile level you are talking about a second line is really an easy permanent fix. I say go for it!
Only problem is the breaker box is in the finished portion of the basement, and to get to the area under the family room requires going through the finished part. Afraid the ceiling and walls would have to get cut out and then patched. Would be an expensive job.

I'm hoping to sell the house in about 2 years and build a new one. Hate to spend more on this house considering the buyers wouldn't care about the extra outlet and pay more.

There is an area in the ceiling running toward the box that has the steel support ,and maybe the wire could be fed down along that. Could mean not much cutting of drywall.
 
Only problem is the breaker box is in the finished portion of the basement, and to get to the area under the family room requires going through the finished part. Afraid the ceiling and walls would have to get cut out and then patched. Would be an expensive job.

I'm hoping to sell the house in about 2 years and build a new one. Hate to spend more on this house considering the buyers wouldn't care about the extra outlet and pay more.

There is an area in the ceiling running toward the box that has the steel support ,and maybe the wire could be fed down along that. Could mean not much cutting of drywall.
You would be amazed how easy a powerline can be fished through finished ceilings by a talented wire puller.
 
Robert,

That's why I use a 30A breaker to supply the energy to my room, and also have a 20A balanced AC Line Conditioner (BPT Singnature 3.5 Plus). I do not play my system too loud, but if I want to be a show off of its power, I cranked up for some time, having only crystal clear sound, even that it is evident the I am playing the system very loud.

My system with this Power Line Conditioner, does not compress the sound at all. I also have a separated copper welding rod for my AC circuit. Costa Rican energy is not too clean, so using a balanced line conditioner solved my problem: clean AC to power my system.

Our Mains AC line is same as yours, 120 V.AC. Our wall socket is the same, one hot 120V line, one neutral and ground. The balanced line conditioner uses 2 hot lines and the center is ground. This unit has a big toroidal transformer, the unit weights about 80 pounds, and here is the wiring:

View attachment 20914
There are other Balanced AC Line Conditioners that offers about the same 20A. It is wise to have more energy reserved of the total power consumption of the system.

When I use this BPT for the first time, my ears were so happy, that I was rediscovering all my music.

Happy listening!
The BPT Signature 3.5 Plus sounds like an improved version of the original Tice Power Block.
 
Thinking about what I might run into if I replace my subwoofer I have now with a more powerful one. I now have my home theater just set up in the family room. Right now I am using a ML Depth i. Just one. I also am running my Aragon dual channel amp (200 watts at 8 ohms each channel), my Marantz receiver that is 11 channel, the tv, bluray, sonos, 2 Prodigy speakers, cable box, and God knows what else on it. Right now the circuit seems fine.

Wondering about that regular 15 amp circuit. Im pretty sure the whole room is just running off of one 15 amp circuit. Looking at the breaker box I see what looks like just one breaker.

The Depth i I am using now is only 350 watts. What if I went to the Balanced force 212 which is 1700 watts MartinLogan | BalancedForce 212 , or maybe this Monolith M 215 that is 2000 watts Monolith by Monoprice M-215 Dual 15" THX Ultra Certified 2000-Watt Powered Subwoofer - Monoprice.com

I wonder if just that one circuit would be safe and/ or not trip. Ive got multiple power outlets on the wall by the home theater setup, but of course those are all in the same circuit since they are in the same room id assume? I had the house built but at the time I didnt consider such things, wish I had. I dont want to think about the trouble and expense it would take to run a new 20 amp outlet up to that room. The breaker box is of course in the basement and half of the basement is finished, so running the wire would be terribly difficult without tearing up drywall I think.

I know there is a formula Voltage x Current = Watts. So a 15 amp circuit should handle up to 1800 watts. Is it as simple as looking at the RMS wattage of the amplifier on the subwoofer? The monolith is 2000 watts RMS but 3600 peak. Is it a simple 1:1 ratio of the rated power of the amp to watts supplied by the circuit? Going by that then the sub wouldnt be safe to run just by itself on a single 15 amp circuit. I see on the website that people are indeed running it on those circuits just fine. I would guess that those people have other things running of that circuit as well, like me. It just sounds a bit risky. Trying to figure out what will be the case before I buy something.
Output power of an amp is not the same as it's current draw on the mains line. I better way to estimate mains load is to look at the mains fuses used in your equipment. If the mains fuse is say 3A, the steady draw would not be more than about 360W at 120V regardless of the amp's rated output power.. The instantaneous transient draw may be much higher at times though depending on the music being played. In any case, two different 1000W amplifiers may draw much different amounts of mains current. For example: my 60W ARC D-70 MKII amp has a 5 amp slo blow line (mains) fuse which means that it may draw up to 600W from the mains for about a second at any given time.
 
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You should be fine. I am running a Bryston 4B3 to a pair of Magnepan 1.7i's, a 3400 watt Paradigm subwoofer, preamp and cd player off a single 15 amp outlet and have never had any problems.
 
Thinking about what I might run into if I replace my subwoofer I have now with a more powerful one. I now have my home theater just set up in the family room. Right now I am using a ML Depth i. Just one. I also am running my Aragon dual channel amp (200 watts at 8 ohms each channel), my Marantz receiver that is 11 channel, the tv, bluray, sonos, 2 Prodigy speakers, cable box, and God knows what else on it. Right now the circuit seems fine.

Wondering about that regular 15 amp circuit. Im pretty sure the whole room is just running off of one 15 amp circuit. Looking at the breaker box I see what looks like just one breaker.

The Depth i I am using now is only 350 watts. What if I went to the Balanced force 212 which is 1700 watts MartinLogan | BalancedForce 212 , or maybe this Monolith M 215 that is 2000 watts Monolith by Monoprice M-215 Dual 15" THX Ultra Certified 2000-Watt Powered Subwoofer - Monoprice.com

I wonder if just that one circuit would be safe and/ or not trip. Ive got multiple power outlets on the wall by the home theater setup, but of course those are all in the same circuit since they are in the same room id assume? I had the house built but at the time I didnt consider such things, wish I had. I dont want to think about the trouble and expense it would take to run a new 20 amp outlet up to that room. The breaker box is of course in the basement and half of the basement is finished, so running the wire would be terribly difficult without tearing up drywall I think.

I know there is a formula Voltage x Current = Watts. So a 15 amp circuit should handle up to 1800 watts. Is it as simple as looking at the RMS wattage of the amplifier on the subwoofer? The monolith is 2000 watts RMS but 3600 peak. Is it a simple 1:1 ratio of the rated power of the amp to watts supplied by the circuit? Going by that then the sub wouldnt be safe to run just by itself on a single 15 amp circuit. I see on the website that people are indeed running it on those circuits just fine. I would guess that those people have other things running of that circuit as well, like me. It just sounds a bit risky. Trying to figure out what will be the case before I buy something.
Not simple at all. A class AB amplifier is maybe 50% efficient, meaning if the amp is putting out 400 continuous total watts, you'll need 800 watts, which translates to about 6.7 amperes RMS. For class A, the efficiency drops to about 25%. Subwoofers, including ML's, tend to be class D, which is much more efficient, so continuous watts in approximately equals continuous watts out. On the other hand, you're rarely if ever going to be running your amps, and especially your subs, at anything even close to the rated continuous output.

Bottom line: if your house is wired correctly and safely, the only down side of exceeding your current capacity is popped breakers. Why not just try it? If you're popping breakers regularly, deal with it then. One caveat: if you're running a projector that should be on a separate circuit, otherwise interrupting power without proper cool-down could cause lamps to blow out or, worst case, explode.

It's not necessarily the case that all the receptacles in a room are on the same circuit. But sometimes, running an audio system on different circuits can cause hum problems, especially if they're on opposing phases of the 240V service line feeding your home. Try throwing breakers and see which outlets die and which stay alive. In fact, it's a good idea to label which breaker everything in your house is on. I put labels behind outlet or switch plates. I have a tester that you plug one end into the circuit you want to test and you take the other end down to your breaker panel. It makes a chirp when you're near the correct breaker. Sometimes it's ambiguous, but if you throw the breaker and it stops, you know you've hit it. For added safety, the light on the transmitter end will be out.

If you're worried about clean power, that's a separate issue. Increasing service capacity isn't going to clean up your power. If you're wiring is old, you may find voltage sags when you, for example, power up your monster power amps or subwoofers. Especially if your equipment is at the end of a long line of daisy chained receptacles with the back entry poke-through connections used. In that case remediation by an electrician, or if you're confident of your skills, yourself, may be indicated. Just be sure you don't violate any local electrical codes. Worst case, in the event of trouble, it could void your fire insurance.
 
You would be amazed how easy a powerline can be fished through finished ceilings by a talented wire puller.
As someone with lots of wire pulling experience, both in homes and industrial settings (broadcast plants) I'd be amazed if it were that easy. You nearly always run into something you didn't expect, like fire stops. Also, be sure to look at the requirements for "old work" wiring. Some things like the number of places the cable needs to be anchored down, may be relaxed. Others may not be. Depends on your local codes.

One common trick for old work wiring is to pry loose the molding at the bottom of the wall, if you have it. Then you can cut through the wall there without having to worry about refinishing, just replace the molding. You can drill holes in the studs and fish the wires through, as is usually required at least for new work wiring--and put shields over the studs to prevent someone in the future from finding a stud and deciding it is a good place to drill. Anytime you're cutting or drilling walls, you have to be careful not to hit any existing wiring. Most electronic stud locators will tell you. Whatever you do, check your local codes.
 
Not simple at all. A class AB amplifier is maybe 50% efficient, meaning if the amp is putting out 400 continuous total watts, you'll need 800 watts, which translates to about 6.7 amperes RMS. For class A, the efficiency drops to about 25%. Subwoofers, including ML's, tend to be class D, which is much more efficient, so continuous watts in approximately equals continuous watts out. On the other hand, you're rarely if ever going to be running your amps, and especially your subs, at anything even close to the rated continuous output.

Bottom line: if your house is wired correctly and safely, the only down side of exceeding your current capacity is popped breakers. Why not just try it? If you're popping breakers regularly, deal with it then. One caveat: if you're running a projector that should be on a separate circuit, otherwise interrupting power without proper cool-down could cause lamps to blow out or, worst case, explode.

It's not necessarily the case that all the receptacles in a room are on the same circuit. But sometimes, running an audio system on different circuits can cause hum problems, especially if they're on opposing phases of the 240V service line feeding your home. Try throwing breakers and see which outlets die and which stay alive. In fact, it's a good idea to label which breaker everything in your house is on. I put labels behind outlet or switch plates. I have a tester that you plug one end into the circuit you want to test and you take the other end down to your breaker panel. It makes a chirp when you're near the correct breaker. Sometimes it's ambiguous, but if you throw the breaker and it stops, you know you've hit it. For added safety, the light on the transmitter end will be out.

If you're worried about clean power, that's a separate issue. Increasing service capacity isn't going to clean up your power. If you're wiring is old, you may find voltage sags when you, for example, power up your monster power amps or subwoofers. Especially if your equipment is at the end of a long line of daisy chained receptacles with the back entry poke-through connections used. In that case remediation by an electrician, or if you're confident of your skills, yourself, may be indicated. Just be sure you don't violate any local electrical codes. Worst case, in the event of trouble, it could void your fire insurance.
Well, I added an additional 21 inch subwoofer with 1920 watts and also have a BF 210 sub now too. Everything is on one 15 amp circuit and I've had zero problems. We built the house new in 2008, so the wiring is relatively new. There's only one breaker in the box for the family room. There is a Marantz 11 channel receiver and an Aragon 200 watt/channel stereo amp running on it as well. Then there's the TV and other components too.
 
As someone with lots of wire pulling experience, both in homes and industrial settings (broadcast plants) I'd be amazed if it were that easy. You nearly always run into something you didn't expect, like fire stops. Also, be sure to look at the requirements for "old work" wiring. Some things like the number of places the cable needs to be anchored down, may be relaxed. Others may not be. Depends on your local codes.

One common trick for old work wiring is to pry loose the molding at the bottom of the wall, if you have it. Then you can cut through the wall there without having to worry about refinishing, just replace the molding. You can drill holes in the studs and fish the wires through, as is usually required at least for new work wiring--and put shields over the studs to prevent someone in the future from finding a stud and deciding it is a good place to drill. Anytime you're cutting or drilling walls, you have to be careful not to hit any existing wiring. Most electronic stud locators will tell you. Whatever you do, check your local codes.
I had a guy run speaker cables for four Atmos ceiling speakers in my family room and it took about 5 or 6 hours just to install them. Getting the wires to turn the 90 degree angle from the wall to the ceiling was the tough part. Luckily the are under the family room is still unfinished, so that helps.
 
You should be fine. I am running a Bryston 4B3 to a pair of Magnepan 1.7i's, a 3400 watt Paradigm subwoofer, preamp and cd player off a single 15 amp outlet and have never had any problems.
That's pretty typical. I'm running a pair of Parasound JC3 monoblocks in high bias mode (class A up to 20 watts) and a ML Descent i sub on the same 15A circuit, and hardly ever had a problem. The only time I did have a problem is when I was cutting a piece of 1-1/2" butcher block, for a turntable shelf, up in the attic, with a Delta table saw rated at 15A. I habitually leave the stereo on for long periods, and forgot the newly acquired Parasounds, on the same circuit, are set to draw a substantial standing current. A dedicated circuit for the stereo would be nice but frankly, getting a couple of 20A circuits up to the attic workshop, for power tools and heating/AC, is a much higher priority for me. Also, I don't think the saw really draws 15A all the time, just when under load like cutting 1-1/2" oak.

The incident also reminded me to turn off the stereo more often. The Parasounds supposedly have an "instant warm-up" feature. I shouldn't really be paying to run room heaters when I'm not using them (even though one of my cats really appreciates it). I've listened critically to the amps when first turned on versus when they've been running for hours, and never really noticed a difference. If I did notice a difference, I'd have to weigh the costs and benefits.
 
Then there's the TV and other components too.
OK, so no projector. That, as I said, could be a problem if it suddenly lost power. At the university where I work I did recently see a projector lamp fail from short-cycling. The pieces were well contained in the lamp unit, though.
 
OK, so no projector. That, as I said, could be a problem if it suddenly lost power. At the university where I work I did recently see a projector lamp fail from short-cycling. The pieces were well contained in the lamp unit, though.
Thanks for that information. I will try to remember that. I plan on building a home theater with a projector in the future. I had no idea that could happen. So I guess to be safe, run a separate 15 A circuit just for the projector?
 
Hola Chicos,

Here is a little tip regarding the system's energy consumption. Once you have been listening for a half an hour, touch the cable's male plug connected to the wall. It should be cold. If it is warm, this power cord is not suppling the enough energy from the wall's Mains AC. Using a thicker power cord will reduce dramatically the heat. Also touch all energy power cords for warm or hot plugs. If that's so, a thicker power cord will work. Also, your system will sing much better, with tons of dynamics and definition.
 
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If we ever get to build again, I'm putting in multiple 20 amp circuits in the home theater room. Doing it while building doesn't cost too much, and it's good for piece of mind. I've learned on here to run a separate line for the projector too. Lots of circuits. Heck, make a separate small breaker box just for the theater!
 
If we ever get to build again, I'm putting in multiple 20 amp circuits in the home theater room. Doing it while building doesn't cost too much, and it's good for piece of mind. I've learned on here to run a separate line for the projector too. Lots of circuits. Heck, make a separate small breaker box just for the theater!

I recently made use of services of a practically skilled electrical technician. I connected three air conditioners and two refrigerators to source of house electricity. All were high electrical energy consumption appliances, especially the air conditioners. Took the electrician 5 days to complete task.

Used 6mm square electrical cable. Over spec. I was told by my electrician since he recommend 4mm square cable. The 6mm square cable is rated for or can take 450 to 750 volts maximum. I assume without heating up.

In addition I do not know and neither does practically skilled technician how to calculate or what exact value to use for circuit breakers. Again went for over spec. Used 32 ampere circuit breaker for each air conditioner and 10 ampere for each refrigerator. Do not recommend over spec. in ampere capacity size of breaker. We were ignorant.

Another over spec. was to use one 6mm square wire for each electrical appliance all the way to the source of electricity or three phases.

Of importance is electrical wire thickness first and close second ampere rating of the wall plug. You can go for over spec. for both will not hurt. There is a higher price to pay for thicker cable. Cable was most expensive. Price wise a distant second were the 32A breakers. Electrician fee was slightly greater than total price of all 5 circuit breakers.

The breaker simply limits the current to its rated amperes for example 20A and not greater can pass. Some time ago for each 18000 BTU air conditioner I had 20 A breaker. The air conditioner kept switching off because need more than 20 ampere current. Then I replaced with 30 ampere peak capacity breaker and the problem disappeared.

The electrical connection when plug is inserted into wall plug must be tight or very tight. Otherwise if loose will cause plug to melt and wall plug internals to melt. If not immediately addressed then danger of fire starting.
 
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