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Andrew Longman
05-06-13, 10:30 AM
I am trying to help our minister get the hum out of his PA system so he can record his sermons. There is actually no hum in the PA that I can detect and when listening during the recording through the PC connected to the PA system I don't here any hum, but when playing back the recording through Media Player there is a distinct 60hz hum.

I assume it is a grounding issue of some sort but don't know where to start.

Thoughts from the Oc braintrust?

dando
05-06-13, 11:18 AM
I am trying to help our minister get the hum out of his PA system so he can record his sermons. There is actually no hum in the PA that I can detect and when listening during the recording through the PC connected to the PA system I don't here any hum, but when playing back the recording through Media Player there is a distinct 60hz hum.

I assume it is a grounding issue of some sort but don't know where to start.

Thoughts from the Oc braintrust?

I had that same issue with the family room system when I added a media server (Turtle Beach). I did a bit of research and was advised to get an adapter for the AC plug. Worked like a charm. You can also do the AVSForum mosh pit :saywhat: for advice.

-Kevin

nrc
05-06-13, 11:21 AM
Audio hum is usually from a ground loop. A ground loop occurs when different parts of the system have their ground at different potential (voltage) relative to earth ground.

http://www.yamaha.com/yamahavgn/Images/ProAudio/Ground_Loop_Diagram_01_Main.jpg

There are detailed explanations of how to avoid that at the link below but the short version is to get all your grounds at the same potential relative to earth ground (ideally zero).

Given that you're not hearing the hum over the PA it's likely a ground loop between the PA and recording device.

Make sure all your equipment is plugged into a properly grounded outlet - the same one if safely possible. You may need to get an outlet tester to make sure that your outlet is properly grounded.

Make sure that all your interconnections between components have a good ground connection between the components. If the components support it use three wire balanced connections.

http://www.rane.com/note110.html

WickerBill
05-06-13, 11:42 AM
How is the signal leaving the sound board? Is it XLR leaving the board and 1/8" stereo entering the PC? Is the sound going to the PC from a direct output or is it being split from the house mix?

If you spend more than an hour trying to find it and can't, or if you find it is going to be difficult to fix (electrical), I'd highly suggest just picking up one of these:

http://www.zzounds.com/item--EBTHE2PKG


Eliminates ground loops instead of other tools that filter or mask.


/church sound jockey for 29 years

gerhard911
05-06-13, 11:54 AM
Ground loops can be a b!tch to sort. As nrc suggests, proper AC wiring with a single ground path to earth for the whole system is ideal but many times impossible to achieve.

As a workaround, the adapter Kevin refers to turns a grounded 3 plug AC connection into an ungrounded 2 plug. I have done this when desperate but not the safest solution.

I have used this Radio Shack ground loop isolator (http://www.radioshack.com/product/index.jsp?productId=2062214) on occasion with good success.

Here is a much less expensive ground loop isolator (http://www.monoprice.com/products/product.asp?c_id=108&cp_id=10844&cs_id=1084402&p_id=6909&seq=1&format=2) that I have not tried but I have purchased many products from Monoprice and never been burned.

Based on your problem description you would place this device in the PC's audio out path.

dando
05-06-13, 12:14 PM
As a workaround, the adapter Kevin refers to turns a grounded 3 plug AC connection into an ungrounded 2 plug. I have done this when desperate but not the safest solution.


Correct. It was a simple solution for one component (Turtle Beach AudioTron). None of the other components (plugged into the same power strip) had any issues. :saywhat: I wouldn't have used that solution for any high power devices.

-Kevin

datachicane
05-06-13, 12:37 PM
Sketchy grounds are nothing to screw around with. You don't want your pastor to do a Keith Relf.

Andrew Longman
05-06-13, 01:40 PM
Thanks. I am going down to the church in a bit and I will start by seeing how everything is plugged in.

From what I remember this morning the PC and monitor are plugged into a wall socket, there is some sort of newer preamp for the PA that may be plugged into that as well. Then there is a decades old PA system bolted into the wall that I think is hard wired with a master on/off light switch connection.

He also said they used to have a "digital recorder" (before they added the PC)that worked without a hum but had a really low signal and poor volume. That's why they moved to the PC (and so they could on occasion display Powerpoint slides)

dando
05-06-13, 04:21 PM
Powerpoint sermons. All kinds of awesome there. :D

-Kevin

Andrew Longman
05-06-13, 06:25 PM
Powerpoint sermons. All kinds of awesome there. :D

-Kevinfortunately no. Real fortunate. :D

Hymns, yes. For the old folks who can't read the type in a hymnal

And occasionally something funny off youtube just for the kids.

FWIW you gotta understand the church is more of a full service community center for this dinky little town because services don't exist otherwise. We have all types of faiths and non faiths that show up just because it is a place to get help for what ails you from the town folks (e.g., there are I think 5 AA meetings a week there as well as a food pantry and a youth group) and/or just stay connected to what's going on. It drives the powers that be in the Presbyterian church crazy but its been working that way for about 50 years and the members/town aren't going to change a thing.

nissan gtp
05-06-13, 06:59 PM
"Out yeah sound of the Devil !!"

dando
05-06-13, 08:41 PM
fortunately no. Real fortunate. :D

Hymns, yes. For the old folks who can't read the type in a hymnal

And occasionally something funny off youtube just for the kids.

FWIW you gotta understand the church is more of a full service community center for this dinky little town because services don't exist otherwise. We have all types of faiths and non faiths that show up just because it is a place to get help for what ails you from the town folks (e.g., there are I think 5 AA meetings a week there as well as a food pantry and a youth group) and/or just stay connected to what's going on. It drives the powers that be in the Presbyterian church crazy but its been working that way for about 50 years and the members/town aren't going to change a thing.

Our local community church is the same. Hosts AA meetings and has a food pantry as well. My girls attended pre-school there for 3 years. The local Catholic church not so much. Even the local Episcopal church hosts AA meetings, etc. I don't get into denominations much, but the Catholics can kiss my ass. Religion of convenience, IMO. And I'm a Catholic by baptism. :irked:

-Kevin

Gnam
05-06-13, 08:59 PM
IBTL. :D

Religion is a lot like wiring. The devil's in the details. :p

TravelGal
05-06-13, 09:21 PM
FWIW you gotta understand the church is more of a full service community center for this dinky little town because services don't exist otherwise. We have all types of faiths and non faiths that show up just because it is a place to get help for what ails you from the town folks (e.g., there are I think 5 AA meetings a week there as well as a food pantry and a youth group) and/or just stay connected to what's going on. It drives the powers that be in the Presbyterian church crazy but its been working that way for about 50 years and the members/town aren't going to change a thing.

Sounds fabulous. IMHO, it's a *real church.* Not just a management vision of rules and regs. TravelMom had a church like that. It was a wonderful but hierarchy finally got the best of it. :irked:

datachicane
05-06-13, 09:56 PM
Religion is a lot like wiring. The devil's in the details. :p

:thumbup:

WickerBill
05-06-13, 09:57 PM
IBTL. :D



I laughed

cameraman
05-07-13, 03:26 AM
Our local community church is the same. Hosts AA meetings and has a food pantry as well. My girls attended pre-school there for 3 years. The local Catholic church not so much. Even the local Episcopal church hosts AA meetings, etc. I don't get into denominations much, but the Catholics can kiss my ass. Religion of convenience, IMO. And I'm a Catholic by baptism. :irked:

-Kevin

Huh, that must be a Diocese thing because the Catholic Diocese of Salt Lake runs one of the largest soup kitchens in the state serving up about a thousand meals every day. They run the day center downtown that has the showers, laundry facilities, and day shelter with the job search assistance facility. They are also one of the larger providers of emergency rent, utilities and food aid in town. While they don't do a.a. they do run a residential substance abuse treatment facility in town. They are a major player with the United Way of Salt Lake through the Catholic Community Services and the Holy Cross Ministries. Granted they don't run those services out of the churches themselves but most are such small buildings (~3800 sq ft:saywhat:) as to be of little value when it comes to much of anything beyond services & confession.

dando
05-07-13, 06:08 AM
Huh, that must be a Diocese thing because the Catholic Diocese of Salt Lake runs one of the largest soup kitchens in the state serving up about a thousand meals every day. They run the day center downtown that has the showers, laundry facilities, and day shelter with the job search assistance facility. They are also one of the larger providers of emergency rent, utilities and food aid in town. While they don't do a.a. they do run a residential substance abuse treatment facility in town. They are a major player with the United Way of Salt Lake through the Catholic Community Services and the Holy Cross Ministries. Granted they don't run those services out of the churches themselves but most are such small buildings (~3800 sq ft:saywhat:) as to be of little value when it comes to much of anything beyond services & confession.

Could well be and I hate to paint them all with a broad brush, but there is a stark contrast b/w the local Catholic parish and the Dublin Community Church. Another example locally is the firing of a teacher at one of the local Catholic schools because she was found to be gay. She taught PE at the school for 19 years. She was 'outed' in her mother's obituary, which mentioned her partner, and consequentially fired. That type of intolerance is simply disgusting. :irked:

-Kevin

WickerBill
05-07-13, 06:20 AM
b/w is black and white. Still

dando
05-07-13, 09:00 AM
b/w is black and white. Still

b&w...YMMV. :gomer:

EDIT: it varies...

http://wiki.answers.com/Q/What_is_the_abbreviation_for_between

-Kevin

Indy
05-08-13, 12:25 AM
That type of intolerance is simply disgusting. :irked:

-Kevin

Amen, brother.

cameraman
05-08-13, 12:09 PM
Could well be and I hate to paint them all with a broad brush, but there is a stark contrast b/w the local Catholic parish and the Dublin Community Church. Another example locally is the firing of a teacher at one of the local Catholic schools because she was found to be gay. She taught PE at the school for 19 years. She was 'outed' in her mother's obituary, which mentioned her partner, and consequentially fired. That type of intolerance is simply disgusting. :irked:

-Kevin

You have to remember that I'm in Utah so the Catholics are part of the oppressed minority.:D This is one of the few places that you will find Unitarians, Catholics, Presbyterians, Jews, Buddhists, Episcopalians, Methodists and half the Lutherans:saywhat: formally working together on so many issues. The Catholics have a very large school system in Salt Lake, more than half the students aren't Catholic...

Andrew Longman
05-08-13, 11:29 PM
You have to remember that I'm in Utah so the Catholics are part of the oppressed minority.:D This is one of the few places that you will find Unitarians, Catholics, Presbyterians, Jews, Buddhists, Episcopalians, Methodists and half the Lutherans:saywhat: formally working together on so many issues. The Catholics have a very large school system in Salt Lake, more than half the students aren't Catholic...and in my time in SLC, from direct observation (without elaboration I haven't been a customer, but an interested party), the Mormons set a high and admirable bar for the quality and substance of help for those in need.

It is a great place to be in dire straights and I don't in any way mean that to be funny or a reference to Mark Knopfler.

:)

WickerBill
05-09-13, 06:57 AM
Great. Now I'll be singing Brothers In Arms all day.

Andrew Longman
05-13-13, 09:51 AM
It worked.

Plugging it all into a common ground did the trick.

Thanks much to all who contributed. The minister thinks I am a genius. I told him I just have a lot of very smart old friends. :)

nrc
05-13-13, 11:46 AM
It worked.

Plugging it all into a common ground did the trick.

Thanks much to all who contributed. The minister thinks I am a genius. I told him I just have a lot of very smart old friends. :)

Very smart old friends, or very old smart friends? :)

Andrew Longman
05-13-13, 01:09 PM
Very smart old friends, or very old smart friends? :)

Just old friends. Members can self select if they want to also be considered smart or well-seasoned (like good firewood) or both. ;)

Thanks again all for being here.

Andrew Longman
06-03-13, 04:09 PM
Since y'all helped sort this out I thought I would offer something back.

Patrick (our pastor) now has successfully recorded and posted three sermons. They are a three part series on the discipline of spirituality and if you are so inclined they might be worth your while.

None require IMO a Christian faith, though the context is the teachings of Jesus. Acceptance that spirituality happens in some form or another and Jesus might have had something worthwhile to say about it,as well as some curiousity about how your condition might be a bit better pretty much are the only requirements. Well, that and a sense of humor.

For whatever reason, at this moment in my life I find Patrick to be a practical and valuable resource.

Part one is about how Jesus didn't intend to start a church but rather a community of people dedicated to a spiritual life.

Part two is about the importance of not living life by "checking the box" or "trying" to be better but rather practicing bit by bit to live more spiritually

Part three is the "Party on, Garth" sermon about the importance and spiritual requirement to celebrate.

Anyway, do as you like with it. but at least take satisfaction that you helped.

Now I just need to figure out how to get it to work on a mobile device and allow MP3 download.

http://fpc.frenchtownpres.org/?m=201305

http://fpc.frenchtownpres.org/?m=201306

BTW each recording starts with a reading before the actual sermon starts.