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Old 1st May 2012, 08:49 PM   #22871
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Quote:
Originally Posted by simon7000 View Post
Since you probably can't get below the frost line use a piece of copperweld or solid copper wire buried as deep as you can get it. Then place rocks to hold it done before refilling the dirt.
I'll have to hunt for a place, but I love my trees! My wife would like to cut them all down for a panoramic view, but since we are <75' from the tide line it requires several agencies to agree.
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Old 1st May 2012, 09:01 PM   #22872
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Quote:
Originally Posted by scott wurcer View Post
I'll have to hunt for a place, but I love my trees! My wife would like to cut them all down for a panoramic view, but since we are <75' from the tide line it requires several agencies to agree.
It doesn't have to be a straight line. Just trench from the house out and between the trees.

Then there was the local fellow who lived on a hillside. He was afraid the trees behind his house might fall on it. So he cut them down. A few years later during a heavy rainstorm, the entire hill came down. The tree roots had been holding it in place.

Now that was totally off topic, should I quit doing color commentary?

Last edited by simon7000; 1st May 2012 at 09:03 PM.
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Old 1st May 2012, 10:46 PM   #22873
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Seldom do US houses achieve 25 Ohms or less resistance to Mother Earth. The first part of the NEC rule is for the 25 Ohm resistance, but to measure this a special meter that costs about $2500 and one hour labor is required. So most residential electricians go to the next part of the rule and just drive a second ground rod.

Older two wire US circuits by rule can be updated with a GFCI receptacle that has an attached label "no ground wire".
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Old 1st May 2012, 11:36 PM   #22874
gpapag is offline gpapag  Greece
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Quote:
Originally Posted by scott wurcer View Post
George,
I had some trepidation in doing an actual music recording since I know a few folks who do this very seriously and was sure there were going to be several "rookie" mistakes. I thank Rob Danielson for pointing out the same rig with omni capsules made nature recordings that were a little too bright and recommended the cartiod capsules to temper this. As you noticed the image is a little flattened front to back, the omnis get the opposite comment in this regard (some of my fields recordings were almost binaural to some). As I said in my article this is where engineering and art coincide.


Scott
I feel I have to apologize to you for commenting on the sound balance of the recording.
Although I have declared “crappy ears”, I have not shown my audiogram (for the fear of inducing some nightmares).These broken ears don’t hear past 11-12KHz, but the worst is that when extended HF is noticeably present in a recording, I kind hear it as something harsh (this doesn’t happen when I listen to live unamplified music, go figure).
Therefore, don’t take my previous comments as anything valid.

And you did very well to deal with live music miking. What you describe as "rookie" mistakes is what can be declared “the norm”. They are so many variables in each set-up. It is a (to be learned) art.


Ref. Your grounding resistance (impedance) measurement, as Simon said, insert 3 rods and before crosswiring them, use them to measure your actual grounding resistance utilizing the 3 prod voltage drop method. Here is some data for guidance and comparison.

http://www.weschler.com/_upload/site...owntoearth.pdf

http://support.fluke.com/find-sales/...15_ENG_A_W.PDF


SY
There is a third tuning parameter with the ground plane mic arrangement.
It is the angle (in the vertical plane) that is formed from the mic axial line and the floor level. It affects the percentage of direct to reflected sound impinging on the diaphragm.
This angle has greater effect the larger the diaphragm surface is.

George
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Old 2nd May 2012, 03:04 AM   #22875
Bonsai is offline Bonsai  Taiwan
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[QUOTE=SY;3007763]Stuart Yaniger's sounds on SoundCloud - Create, record and share your sounds for free


Thanks - I'll take a listen this weekend!
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Old 2nd May 2012, 02:20 PM   #22876
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Quote:
Originally Posted by Speedskater View Post
Seldom do US houses achieve 25 Ohms or less resistance to Mother Earth. The first part of the NEC rule is for the 25 Ohm resistance, but to measure this a special meter that costs about $2500 and one hour labor is required. So most residential electricians go to the next part of the rule and just drive a second ground rod.

Older two wire US circuits by rule can be updated with a GFCI receptacle that has an attached label "no ground wire".
CEM DT-5300 Industrial Digital Earth Ground Resistance Tester Ohm DC/AC Volt Meter

25 ohms is the maximum permitted. 5 ohms is what the telephone company requires.

I had a theatre once where they miswired the rented lighting instruments switching the black and green wires. (The work lights were all tinted yellow.) That meant the hot lead was grounded to the buildings metal framework. The lighting board operator noticed operating the controls above around 60% of the light scale caused the breakers to pop. As these were 10KW or larger (120V) dimmers that could be quite a few amps. It was interesting when it rained as some leaked in an dripped down between metal bits and would sparkle with the electrical discharge.
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Old 2nd May 2012, 04:58 PM   #22877
gpapag is offline gpapag  Greece
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As ligtning has come up as an issue, here is an advanced Ligtning
detector. Some of you can ask for a sample.

Innovative IC can't trap lightning, but can let you know it's coming

AS3935 / Lightning Sensor / RF Products / Products / Home - austriamicrosystems AG

George
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Old 2nd May 2012, 05:11 PM   #22878
bcarso is offline bcarso  United States
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Further off topic but a funny story: on a pit orchestra gig in 1972 the band got to Chicago and checked into the hall before the concert that evening to rehearse briefly. The stand lights all plugged into outlets scattered about the pit.

The guitarist naturally plugged his Fender amp into what appeared to be mains power. After a short time we began to smell something very wrong.

Because tubular incandescents emit a small amount of acoustic hum when powered from AC, the pit was supplied with 115V DC. And worse, that turned the internal fuse of the Fender into a nice metal vapor conductor, and the power transformer rapidly fried. No guitar tonight!
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Old 2nd May 2012, 05:47 PM   #22879
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Sharing the same stlye power sockets??

Criminal!
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Old 2nd May 2012, 06:14 PM   #22880
bcarso is offline bcarso  United States
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Quote:
Originally Posted by cliffforrest View Post
Sharing the same stlye power sockets??

Criminal!
Yes, standard two-wire mains outlets, looking for all the world like normal. But in this one case Edison had won out over Tesla I don't think amplified instruments were the norm for use in that orchestra pit.

It was also a good object lesson: become acquainted with the stage people in a hall new to you at the earliest opportunity. Be nice and respectful!

The whole tour was full of amazing incidents. My saxophone was damaged by baggage crew getting to Seattle, and rendered completely unplayable. Yet a wonderful repairman was located in the city and fixed it in a few hours better than before the damage, and for 25 dollars! I told Dave Chidgey that he could make a whole lot more money if he were to move to LA.

Brad

Another highlight: because of his Japanese wife's Buddhist faith, I got to sit in with Elvin Jones' trio at the Village Vanguard in NYC. Unfortunately the tune was this complex affair with a million changes and a name that sounded suspiciously like one that I knew (no God Bless the Children is not anything like God Bless the Child). I made the best of it, but it was pretty disasterous, particularly as the group was pianoless (Dave Liebman and Gene Perla, if memory serves).

Last edited by bcarso; 2nd May 2012 at 06:21 PM. Reason: afterthought
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