15 amp circuit VS. 20 amp Circuit

I just had a Electricion intall a 20 amp breaker for a dedicated line with a 15 amp receptacle, and said it will be ok. I told him I thought I read something that you can't do that. He said they do it all the time. So I researched it again and it's ok if other circuits are on the 20 amp breaker,but for a dedicated line it has to be a 20 amp receptacle.  Thank God I haven't pluded anything into it yet. Ordered a 20 amp Hospital grade red receptacle. 

Spoke with a friend who is an MIT graduate. And we agreed , based on the power and the amps of 1.2k amps, we need to have each amp its own dedicated 20 amp circuit .( the benchmark amps can be connected to the same circuit )

subwoofers will share , two 20 amp circuits or one 20 amp circuit.

rest can be connected to a regular 15 amp circuit.

for those who suggested , minimum three 20 amp circuit for this equipment .. congratulations, you nailed it .

Hire an electrician.

@speelerr my krell ksa 300s has a 20 amp breaker it doesn't have any fuses.

Sorry joshziggie2021, I didn't realize you wanted to connect a hair dryer together with your "beefy" amp :)

Sorry, this does not make sense.  The amps pull so much power that you need dedicated 20 or 30 amp circuits?  Yet they have internal fuses of "less than 15A"?  This proves my point that these devices pull far less Amps than the "music watts" lead you to believe.

Don't use 10ga romex, every wire has a sound and it's sound is pretty bad for anything other than a sub. I know because that's what I did and now I want to rip it out! I'm back to using the shared 12ga run for now. For that level of system, I'd recommend something like Audience Hidden Treasure, and multiple runs on the same 120v leg. If that's too pricey, then at least buy cryo'ed romex or talk to Weinhart Design about other options they may have.

Just saw this discussion and there are a lot of suggestions that are way overkill for your needs. I total agree with what IMPALER gave you for a good electrical suggestion to give you plenty of power for all your equipment.  To help with voltage drop, I would run 10 gauge wire on the dedicated 20 amp circuit. FYI, I’m also an electrical engineer by trade with over 40 years of power engineering experience. 

@speelerr have you checked the specs of my beefy 1.2k amps ? At 4 ohm, turning up these amps can cause issues. Literally every person I spoke with , recommends a single 20 amp circuit per amp, now I’m being cheap and will put both amps on a single 20 amp circuit per. 
 

that , and 3 other mono blocks pulling 380 watts for home theater , and all that jazz 

Check this out , same was happening to me 

https://audiokarma.org/forums/index.php?threads/new-amps-tripped-circuit-breaker.1000895/

will it all work on a single 15 amp circuit ? YES it will , on very low volume,  that’s not ideal , and yes I want to be able connect a blow dryer if I needed to… you get the idea my EE friend :)

You will NOT have a difference. Period.

@speelerr  I must be misunderstanding your post, most breakers have a trip curve chart, a 15 amp circuit breaker will not trip at 15 amps for a certain time period, which means your equipment could actually draw many times that 15 amps and not trip the breaker if it's for a very short duration of time and it can cause voltage drop. 

@invalid , the “large” short burst of current is feed by the capacitors.  Most amps have an AC line fuse of less than 15amps, therefore, the fuse will blow before the breaker (assuming a 15 amp breaker) 

I rewired my home entertainment system when I saw a good deal on a 125’ spool of 8 gauge wire. There are NO splices along the line and it terminates in a 30 amp plug that feeds the industrial surge protector for equipment in the entertainment center and two hospital grade outlets just outside the center. (Again, all a continuous run without splices.)

The "power consumers" in the center include a Yamaha RX-Z9 Receiver (1,200 watts rated input), a Crown PSA-2XH (eXtended Headroom), bridged, making about 800 watts into a 12 ohm load (20 amp rated input), and a Sunfire Signature sub (2,500 watt disclamer)

The line got it’s own 20 amp breaker, and I even put a big ferrite bead on the line.

The Yamaha SACD became less grainy, but I didn’t really notice any audible difference in the Oppo95, which uses a better power supply.

No, It doesn't work that way.  Just my 2 cents as electrical engineer for over 30 years.  It's all good. :)

@speelerr  tripping the breaker is a separate issue, an amplifier can draw huge amounts of current for very short durations, which will not tripp the breaker, but it will cause a voltage drop. 

Good morning, the music output "Watts" is not equivalent to the actual electrical Watts demanded from the AC outlet. Typically, the manufacturer's label on the device gives the actual load in Amps or Watts and even that has a factor of safety you are not likely to see.  If the music watts were real, every common household with a home theater would be tripping breakers all the time - and long before anything catches fire by design.  Take care!

This has been a great conversation, and an excellent read. What I know (in my system):

Installing dedicated lines for my power amps and signal components made very noticeable SQ improvements. Adding audiophile receptacles added more improvement. Adding well made, high quality power cables with high purity copper added more improvement. In total the improvements were certainly the equivalent of a component upgrade......or just marginally less.

Thanks to all who added to this conversation

@joshziggie2021 AI also says if a shirt takes 3 hours to dry in the sun and pants take 4 hours, then 2 shirts and 2 pair of pants will take 14 hours to dry 

If you have a 200 Amp service in your house, each leg has a capacity of 100 Amps. as long as you don't overload that leg by wiring it for more than 100 amps total, you have no issues. If you have a 400 Amp service, same story, only 200 Amps per leg. if you do as the AI says, you stand a much larger chance of having a voltage differential between neutrals with resulting hum and noise issues. Conventional home wiring was never intended for applications that shared neutrals or grounds across different bus legs.

An AI only knows what it has been taught from it's model. AIs are incapable at this point of creating an original thought, like when to use a parallel process vs. serial process when solving our solar dryer question. Or inferring that minute voltage differentials when loads have different neutrals or grounds will create a differential noise level in a complex audio system.

Same leg of power? That's a multi branch circuit. The best have individual circuits if you can have room on your panel.

I hate multi branch circuit terribly sloppy

Have you measured power consumption of components????

Ratings are not helpful sometimes when it comes to how much Power usage there would be

@jea48 That's the best advice I have read on this thread.

The outlets are not wired in "series" they are wired in "parallel"; series wiring is the old Christmas light string that goes dark when any bulb fails.. Let us assume you have 120 Volt available, and that the breaker and outlets are in good condition, you would need a load of 1,800 watts to reach the breaker's tripping point. These are rough off the top of my head calculations, AC is weird when it comes to Ohm's Law. 1.800 watts would be a very brightly lit room if illuminated by 100 watt bulbs at circuit capacity.

The purposed of a circuit breaker is protection, both load, or appliance, and the distribution system, or wiring. By protecting these two aspects, the structure is protected. If you are tripping your 15 amp- Circuit Breaker it might be that the breaker has aged (and they do age), connections have loosened (like with aluminum wire instead of copper), or maybe some corrosion has occurred at the connections. I would not arbitrarily increase the amperage of a circuit breaker. The danger would be removing the "fuse" function from the breaker, and actually making the wiring the default "fuse", which can produce dire results.

When your house was built the maximum electric loads would have been a table lamp, a clock radio, a vacuum cleaner, maybe a TV. Fortunately there are some easy and inexpensive solutions to this perceived problem. First replace the old, probably aged and poorly preforming Circuit Breaker with a new quality unit that is compatible with the panel. Then replace the outlets with quality units. I wouldn't worry about an orange or red outlet as much as I would be concerned with dissimilar metals at the connections. And, for goodness-sake use the screw terminals not the stab in connections on the outlets. At this point spending money on expensive AC cables (even if said cables are tre chic) could be better spent on the record collection. If you have the disposable income to rewire and replace the service entrance and panel for the house, or just one room,.. good for you. This is NOT a DIY job, and you should have an engineer or Master Electrician involved, be clear about what you want, and obtain the proper permits. The National Electrical Code (NEC) is all about FIRE PREVENTION, really, no kidding.

If you're concerned about the leg issue and ground loops (which I experienced), you might check with your electrician about breaking out into a sub box. 

Great i have some big amps and can only run 2 mono off a 20 amp line.great discussion .I'm a fan of big 10 aug 20 amp lines.the more the better. Math power is amps x volts. In general ee are smart this is what he does. Enjoy the music

@joshziggie2021 what you looked up is correct, but some people would say you could get a ground loop from two different legs, though I have never had this happen. There definitely is voltage drop with a 15 amp circuit, stereophile measures it all the time when measuring high powered amps.

@panzrwagn 

AI says :

Connecting two 20 amp circuits to the same leg of a power source is not recommended as it can overload that single leg, potentially causing issues like uneven power distribution, tripped breakers, and potential damage to your electrical system; it's best to spread the load across both legs of the power supply by connecting circuits to different legs whenever possible

First, a dedicated circuit is always preferable. 

Second, no, your loads are absolutely not connected in series. Loads are connected across the hot and neutral, in parallel.

Third, yeah, probably 3 dedicated circuits, all pulled from the same leg (same side of the breaker box) to minimize potential ground loops and different ground impedances. 

@mickeyb  thanks!  Yes I have some one installing 4 dedicated 20 amp circuits . 

Maybe more of a setup Fritz had with his stack of Krell's

The electrical engineer went to school and studied electric. I would follow his recommendation. I’m a builder and I recommend the same. 3 dedicated outlets. Pretty cut and dry. 

That’s a lot of gear. Honestly if you weren’t going to run them at maximum output all the time you are probably fine so long as you don’t try to turn them all on at once.

The better your wiring to your stereo, the more likely you are to dim the house lights. :) What you should be concerned with is more current on 1 circuit = more voltage drop, and of course, eventually tripping a breaker.

I’d consider running a 60 A sub panel to your room, and from that panel run 2 or 4 dedicated 20 amp circuits. The big advantage is the 6 gauge wiring will result in lower voltage drop overall. Worth considering an in-panel surge protector as well for your gear, both in the main and in the subpanel. It’s not as good as a series mode device (Furman or ZeroSurge) but better than not having them.

You might want to measure your current before doing a bunch of expensive work.  I measured my two subs, which have amps rated at a total of 1100 watts.  Cranked up some bassy music.  They drew 60 watts total.

Hello all,

I had the power company stopping by today . Checked transformer and feed. All is good. Next is for an electrician to install at least two 20 amp circuits

i will update this thread this weekend , whether issue is resolved or not .

Some good comments above from some quite knowledgeable folks - nice to see and is why I like to frequent this forum.   I agree that adding a couple of dedicated 20A circuits with 10-12 AWG wire should do it _ IF the in-wall wiring back to the breaker is the problem.   The only unaddressed point (as of when I started typing) came in the OP's second post where he specifically comments on the lights dimming.               (…the light dimming issue, IS happening…)

More info on how this manifests itself might help us help the OP.  If lights dim, something is not up to snuff somewhere. Are they in the same room and on the same circuit?  If so, then that narrows things down a lot.  If dimming happens elsewhere in the house and NOT on the same circuit, then I would IMMEDIATELY ask an electrician or the utility company to check the service entrance feed to the building. Some utilities won't check past the meter so you may need the electrician for a "last mile" check between the meter and your breaker box.  A non-direct analogy - I once moved into a building and found one leg that fed my stove was leaning against its connecting lug - not clamped at all. Truly scary. Not every installer is working at 100% all the time. There may be a loose connection at one of your outlets or anywhere back to the breaker box or even the pad mount or pole.  

Terminology / grammar check:  You have a SERIES of outlets connected in PARALLEL along the circuit, so each gets the full voltage.  At some point back-wiring came into vogue to speed installation.  That enabled installers to just poke the wires into holes in the back of the receptacle. No loops around screws that need to get tightened just right.  Fast and easy, but not nearly as good a connection and then the receptacle essentially becomes a buss bar and IS in series with the other outlets, but each plug-in point is still in parallel with all the others. 

Another take on the series / parallel issue:  A good wiring job with large wall boxes and lots of space will have the wires going to the breaker box come to a 3-way connection, with the lead to the next box under the wire nut as well as a short pigtail to the receptacle in the box.  This way the receptacle is never in Series with the other devices down the line and the inevitable movement from thermal expansion and years of plugging and unplugging devices has less impact on the connection at each device, and half as many connection points to loosen over time or be suboptimal initially.

15A breaker and 15A outlet circuit?  Some guys may have cut a corner and only used 14 AWG light fixture wire instead of the 12 recomm for outlets, esp since the push-in receptacle back wiring connection holes are not supposed to accept 12 gauge and it is so much quicker, easier and cheaper to just cram the smaller 14 AWG in a hole. You can also get a lot more voltage droop that way.

Back to the HT room.  How / when does the light flicker manifest itself?  During a major but quick explosion, an extended pass of a tank rumbling past you, Aircraft takeoff or extended pipe organ bass note?  A long rumble will deplete much of the stored power in most amp power supply capacitors. Transients are easy, but extended high ampere power response sucks once the caps go flat.  If things blink on even a loud, but SHORT rumble, then maybe a PSU capacitor is no longer up to snuff. Seek it out. Lots of how-to info elsewhere.  I would rotate through my amps and see if I can narrow down my search first. If basic fixtures and wiring were both up to snuff, then the lights should not follow the music.  Upgrading to Audiophile outlets, in-room cables, etc. can be done later if you want as frosting on your cake! 

And also presupposes a dedicated feed for your audio gear, as I was alluding to in my original post.

PS

Some equipment is designed to run on 220 VAC; I recommend that for any high power gear as it minimizes the IR losses (voltage drop) in your feeds.

bigtwin

Exactly correct, wattage rating for a particular appliance is a UL/CE requirement based on very specific tests and results. As I mentioned, those power levels (continuous) are unheard of in home audio. The dimming lights is another issue altogether, and the breaker size isn't going to help that. This is a source power issue, and could be poor connections in the primary feed, under-rated house/apt current supply, generally lower than normal voltage at source, or even an under rated/over utilized transformer at the pole. You have to id the problem before you can fix it.