New electrical wiring specifications

EDIT to my above post.

For some reason #4 Web link no longer works

4) 120Hz buzz   (Make sure volume is turned down first)

Here is the Link. (Turn down your volume first.)

120 Hz Ground Hum SOUND

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@skyy92677 said:

I too just completed a new home build with a dedicated audio room.

New house.

I had a master electrician here 3 times now to no avail. We installed a second earth ground rod on the panel which he claimed should fix it, it did nothing.

Was it your idea to add an additional ground rod to the two that are already there? Adding the additional ground rod wouldn’t have solved your problem. It may have given you a lower soil resistance for the grounding electrode  system for the Earth connection of the electrical service. The main purpose for the connection to Earth is for lightning protection.

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I also have a Siemens whole house surge protector but have the breaker turned off for it as when it’s on the the hum doubles in volume.

It’s so bad that when I turn the whole house surge on you can hear the toaster buzz!

What did the Master Electrician say about the two quotes above problem?

I can not visualize any way the Siemens Type 2 SPD could cause such an event as you have described. The electrical panel should be full of 120V single pole 15 and 20 amp AFCI, (Arc Fault Circuit Interrupter), branch circuit outlet breakers.  An AFCI breaker has a built-in micro processor that senses a series or parallel arcing fault event.  I would think the Siemens SPD would drive the electronics in the AFCI breakers nuts, causing them to trip open on a false arc fault event. 

FWIW, my understanding, for one of the reasons for NEC requiring surge protection at the main electrical equipment panel, was to help protect the AFCI breaker’s internal electronics from high voltage transient surges. If you have the breaker turned off the electronics in the AFCI breakers are not protected.

You said the house was just recently built. I don’t know about your State but my State requires the builder to stand behind any defects, I believe for one year. I suggest you call the builder and tell him you have a serious electrical problem. Ask him if he will have the Electrical Contractor send out a troubleshooting  Service Electrician to look at and fix the problem. 

Before addressing the hum/buzzing issues with your audio system zero in on the Siemens SPD at the electrical panel and the toaster buzzing, (when being used), when the SPD  breaker is closed, (connecting the SPD to the electrical bus) of the panel. Then you can tell the electrician the problem with your audio system. 

Not that it should matter, I assume the toaster uses a 2 wire cord and plug. No safety equipment ground is used.

Just curious, does any of the Links provided below  sound like the buzzing sound you are hearing?

CAUTION, turn down the volume before listening to the examples. Especially the last example. 

This is a standard 60Hz ground loop hum. 

1) 60Hz hum

2) 60Hz audio buzz example

  Or maybe this.

3) 120Hz 

Or maybe this.

4) 120Hz buzz   (Make sure volume is turned down first)

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120Hz could indicate a high level of harmonic distortion on the AC mains. You said you tuned off all the breakers in the panel at one point. Including the Siemens SPD breaker. Only having one breaker on that fed your audio system. Doing so didn’t make any difference. Hum was still present. But not as loud when the Siemens SPD breaker was turned on. I still am shaking my head on that one. Makes no sense what so ever... That’s the first thing the Service Electrician will want you to show him. I would want to see and hear that first hand using the toaster. 

 

How about any neighbors that are fed from the same Utility Power Transformer as your house.  Any solar panels on the roof(s)?   

Are any of the neighbors experiencing electrical problems like you are having?

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@ditusa Said:

Dedicated audio lines I would go with Type MC Galvanized Steel Metal Clad Cable 10/2 with insulated ground. It has better EMI and EF shielding versus Non Metallic cable

I agree on the use of MC (Metal Clad) armored cable. I’m just not a fan of the galvanized steel armored MC cable. I personally would use aluminum  armored  MC cable. 

From my listening experience, as well from that of other audiophiles, galvanized ferrous magnetic steel can add grain as well slightly restrict the openness, air, of the musical presentation.  

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Metal Clad (MC) is manufactured in both steel and aluminum with twisted conductors that help reduce AC magnetic fields. Although the steel jacket helps reduce AC magnetic fields, the twisting of conductors has the greatest effect on reducing these fields.

Another benefit is the constant symmetry of the phase conductors with respect to the grounding conductor which greatly reduces voltage induction on the grounding wire.

The highlighted text is of the greatest importance.

Though NM sheathed cable, (Romex), is good and widely used, I think 2 wire with insulated ground MC cable is better. (Solid copper wire.)

 

To all that may be reading this post, MC armored cable. NOT AC / BX armored cable. Make sure the Electrician buys and installs MC cable.

Example of MC cable: (For purposes of showing the three insulated conductors are twisted together. I am NOT recommending the manufacturer.)

2 conductor with insulated ground MC armored cable  

Note the photo shows solid copper conductors. Ad is for stranded. 

For audio branch circuit wiring solid copper conductors is recommended.

Southwire is a very good cable manufacturer

FYI, though Anti Short bushings are not required by NEC code for MC cable, I highly recommend you tell the electrician you want them installed anyway. If if he says you don’t need them. Tell him, you want them anyway. They are cheap and it will take the electrician about 15 seconds to install one. 

Example:

Pretty simple to install.

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*** AC / BX Armored Cable ***

Make 100% sure the electrician installs MC and not AC / BX armored cable. Big difference between the two.

Southwire Armorlite 125-ft 10 / 2 Solid Aluminum BX/AC Armored Cable

Look closely at the picture of the section of the cable. Note the two insulated copper Line conductors and the bare 16awg aluminum safety equipment grounding/bonding conductor.

 Southwire Website 

10/2 AWG THHN/THWN Insulated Singles Wrapped in moisture-Resistant, Flame-Retardant Paper. 16 AWG Aluminum Bond  Wire. UL Listed. 600 Volts. Rated VW-1. Lightweight Aluminum Interlocked Armor.

"An armor assembly (combination of the interlocked armor & bonding strip) that is recognized as an equipment grounding/bonding conductor per NEC 250.118(8)."

You don’t want this...

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@dhite71 said:

My next project is to run a new circuit to my music room.  I have 12/2 now and am going to move the receptacle to a better location and change to 10/2.  I watched a video with Michael Fremer a few years ago and he said all his equipment was on one circuit and that was recommended.  

That’s not what  Fremer has now. 

https://forum.audiogon.com/discussions/dedicated-power-circuits

Read my post on 02-23-2023 at 04:06pm

I see five 120V branch circuits connected to circuit breakers installed on the same Leg, Line, in the Sub Panel. Read my comments I posted for Fremer’s sub panel.

(Note: The the wiring on the left side of the bottom of the panel. I’m not sure but I think there is a Type 2 SPD, (Surge Protection Device), mounted to the bottom of the panel.)  

 

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