John Sayers' Recording Studio Design Forum Archive

If it were me I would borrow/rent a generator and power the guitar amp. Disconnect power to the whole structure. That will help determine if it's airborn EMI or a line/power issue. If the guitar is quiet with the generator, power up the structure and see if the noise returns.

stuntbutt wrote:If it were me I would borrow/rent a generator and power the guitar amp. Disconnect power to the whole structure. That will help determine if it's airborn EMI or a line/power issue. If the guitar is quiet with the generator, power up the structure and see if the noise returns.

That's a fantastic idea!

Maybe even try running an extension cord from your neighbors house?

Or how about a small battery powered amp? That is what I use to troubleshoot.

friend is it 60hz standard dirty power hum? or a higher tone.

If you are on a true isolated ground. you wont get hum from other circuits, but you still can have dirty power hum. Many power scrubbers under $100 handle this.
It does sound like you should sheild and ground the back of the pickup guard much cheaper than a hardwired transformer

If you want half a chance of one getting this close to right, and understand why and what you want.
Ask if they have done wiring in radio stations, studios, industrial controls or hospital ICU and surgery wings. Industrial control and Hospital electricians are more plentiful. The average box and switch just thinks your spending extra money for a pretty system. Industrial controls and hospital monitors cant have interference and work true, like our music gear.

Back that photo away far enough to show where the isoaltion is a little better

if they are it's not isolated
hard to tell in the photo, but looks like one rod

place the second at least a foot away, and they are not kidding about 8ft deep

you can get a 12" threaded end section of heavy steel pipe and a cap. Makes a nice, dont hit the building with a sledge hammer tool for driving a rod. It easier to place the rodabout a foot away from the building and wire out to it buried to local code depth.

Thanks for the replies. The problem is multi-faceted. Dirty power somewhat, building very close to the power line; not to mention within a mile of the NBC affiliate (TV/FM etc.).

You're right about sheilding the guitar cavity. Only problem is I have many, some of which would be a pain to sheild (vintage Gretsch, for instance).

On the advice of the current electrician, I am adding 2 5/8 copper clad rods, 10', spaced 10' feet apart. That will make a total of four rods, across 32 feet.

I'll keep you guys posted.

Hello, this is my first post.
i felt compelled to do it because i have had the exact same problem.


So i spent about $3400 to rewire my panel.
even tried running an extension cord from my neighbor.
took my guitar and amp to other places to makes sure it was NOT my amp/guitar.
Bought several "anti hum" devices that didn't do a damn thing!
Talked to people who were convinced they knew the problem, but their "fix" did absolutely nothing to help the problem.
Had 3 electricians come out as well.
Also had my guitar tech help me ground my guitar properly.

all did NOTHING.
there was ONE thing that worked...

we took the electric meter completely OUT of the meter junction and hard wired a cord to it to determine it WAS my house/home circuitry that was the problem.
that gave me hope! my hum was GONE! we just had to determine where the culprit was!!
$3400 later. nothing.
whole new panel. wires. ground. the works.


so after a very depressing week, i was just trying different rooms, places and seeing how if i faced a certain way it would lessen the noise...never go away really. It would still be horrible, but you could hear it lessen for sure.

I then decided i was going to search for the WORST spot in the house, the WORST noise. It was near/close to my GAS meter and pipes, and sometimes near the corner of the house. i couldn't figure it out.

so i talked to a friend of mine who is in a rather "big" rock band.
has taken the stage with PANTERA/SLAYER/CLUTCH/LAMB OF GOD...you get the idea.

and i asked him about recording guitars, and interference, he told me about a FARADAY CAGE they had to use in NYC to keep interference out.

so i kept trying to understand WHY there was NO HUM when bypassing my house circuit, but even with a new panel ...the hum was there.
and why walking towards the GAS meter and pipes would make it so much worse??

then it landed on me!

ALL NEW ELECTRIC METERS have a TRANSPONDER in them.
ALL NEW GAS METERS do too. (gas is worse because it usually a STEEL pipe, which acts as an antenna)
ALL NEW WATER METERS have TRANSPONDERS too, (some have phone lines to send the data back)
for the utility companies to read the meters.

That was the culprit.
the actual METERS.
with transponders.

I know, that it seems unlikely. And i am no expert.
But it sounds EXACTLY like the problem i had.

The least you can do is try it. perhaps take your meter out and plug into it with the help of an electrician! like i did?
Or try to shield your meters. or shield your guitar from them with a faraday cage.

maybe even just put some distance between your pickups and the meter!! (know that a super long cord doesnt make sense due to the cord itself not being shielded)

and you can ALSO shield your meter with LEAD/COPPER.
you have to REPORT your reading each month though!

i ended up buying a new house entirely due to this problem!!!
I am married and i couldnt just "over haul" the entire house without upsetting my wife and the family.

When buying the NEW house, it was hilarious, i took a cab, a KRANK head, and a Gibson SG.
Along with a laptop. an SM7B Mic and a SHADOW HILLS gama preamp
ALL to do a MOCK recording of a GUITAR track through a high gain amp!
the real estate agent totally had that "what the ____!!!??" look.



the NEW house has ONE meter outside. and sure enough, the further i go from it...the less "hum" there is. also the more mass in between the meters the better.
please give it a try.
I'm telling you this because i really sympathize with you.
if you have the resources, try to shield your "antenna" basically your guitar from the RF issue.


http://www.twpinc.com/rfi.html

and if you got $$

http://www.hollandshielding.com/faraday/index.php


do tell how things work out.
all the best to you my friend...
i guess i'm part of the forum now!

By the way i also live near a TV station! .7 miles from WMAR TV 11 Baltimore.

Durv

Baltimore MD
443 220 5439

Thanks for all the input guys. I found an engineer at the power company, who was very sympathetic to my problem. Today he and a couple co-workers came over with one of the "big" trucks. After checking a few things, they cut the power on the line altogether.

At that point we ran the amp off the truck's generator; the hum was reduced by 7 dB. One of the higher harmonics seemed much louder, but that could've been from the not-so-clean power coming from the truck. Upon turning the line back on, the noise was bad as ever.

The engineer also noticed that the hum was greatly reduced on the back porch, which is essentially a tin covered roof and sides.

We came to the conclusion the faraday option is the next logical step. My new electrician chickenwire would work fine if installed right (grounded).

Chrisgraff,

please keep us posted.
i am truly hoping that it will be solved for you.
again, MASS definitely helps with RFI, but also of course the copper mesh.
Tin is good too, but copper mesh as in microwave shielding works best. scientifically of course.

that is absolutely wonderful that you have a power company that treats you like a human. Very fortunate! Another option is to further test, is to remove the "meter/transponder" and turn OFF other meter transponders for WATER/NATURAL GAS/.

please do post back. best of luck to you my friend
Durv

Hi Chris,

Hey, if i remember correctly, didn't we read some low voltage on your ground line as well? I've been studying some alternative power options recently, and in the process, I learned something very interesting. The power company typically grounds their systems using galvanized rods (zinc). You have installed copper rods. Guess what happens when zinc and copper is connected together? It creates what is known as a "battery effect". Essentially you are creating an earth battery and injecting voltage into your ground system possibly as well.

I do like the faraday cage idea though. copper mesh is best, but extremely expensive.

Wow, six years later!

That battery effect is DC and with low impedance power wiring, it's voltage is just about zero.

I received an email that there was a new post on this thread, so I replied. BTW, how is the studio doing? Did you finally get some of the quirks worked out? A lot has changed in 6 years. I've gotten married, and now expecting a little one in December.

I received an email that there was a new post on this thread, so I replied.

Yeah, there was a spammer that spammed a few threads (including this one) before I managed to block him permanently and delete his trash.

- Stuart -