HELP: Killing a Microphone at DVinfo.net
DV Info Net

Go Back   DV Info Net > The Tools of DV and HD Production > All Things Audio
Register FAQ Today's Posts Buyer's Guides

All Things Audio
Everything Audio, from acquisition to postproduction.

Reply
 
Thread Tools Search this Thread
Old July 29th, 2005, 08:17 PM   #1
New Boot
 
Join Date: Oct 2004
Location: Fayetteville, Arkansas
Posts: 15
HELP: Killing a Microphone

I'm try to shoot a short film with some friends, and we're borrowing all of the equipment we can get. We're shooting on a JVC 5000 series broadcast camera (borrowed from the journalism department), and we were hoping on borrowing a broadcast quality boom mic, but our source fell through.

Instead, we were able to borrow a prosumer electret condenser microphone from someone else. It connects to the camera with a miniplug, but the camera has only XLR connectors. This morning, we were able to borrow a converter, or, rather, two converters stuck together (1/8-1/4 miniplug adapter stuck into a 1/4 miniplug to XLR connector.)

Everything snapped into place comfortably. We tried the mic, and had no luck. We adjusted all of the channel settings, and had no luck. We changed batteries inside the microphone twice, and tested those batteries in a digital camera. They worked.

We then tried the microphone by plugging it into the sound card of a computer. It didn't pick up any sound either.

When I looked back at the camera, I saw that where we plugged in the xlr connector, there were three switch options: line, mic, and mic+45V. I believe that we had it plugged in on the last option, and I'm worried that the 45 volts may have damaged the microphone permanently, and that we now owe our friend a new one.

Is this possible? Probable? Is there anything else we should check for?

Thanks for all your help. This is a great forum, and I've learned a lot here.
Chris Carera is offline   Reply With Quote
Old July 29th, 2005, 09:45 PM   #2
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Chris, I think you can relax. It's not likely that 45V would hurt the mic. If battery powered XLR mics were designed such that accidental application of standard phantom voltage would hurt them, there would be a lot of fried mics out there. Besides, the hookup you described is a pretty good indication that the mic wasn't even getting the voltage.

Coincidentally, for an explanation of why the mic didn't work, and what to do about it, see the post just below this one (from Scott Brickert) that I just finished replying to.
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply With Quote
Old July 30th, 2005, 09:26 AM   #3
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,337
Quote:
Originally Posted by Chris Carera

We then tried the microphone by plugging it into the sound card of a computer. It didn't pick up any sound either.

When I looked back at the camera, I saw that where we plugged in the xlr connector, there were three switch options: line, mic, and mic+45V. I believe that we had it plugged in on the last option, and I'm worried that the 45 volts may have damaged the microphone permanently, and that we now owe our friend a new one.

Is this possible? Probable? Is there anything else we should check for?

Thanks for all your help. This is a great forum, and I've learned a lot here.

Applying 48 V DC Phantom Power to an unbalanced microphone can destroy it.

Ty Ford
Ty Ford is offline   Reply With Quote
Old July 30th, 2005, 11:40 AM   #4
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Chris Carera
...
We then tried the microphone by plugging it into the sound card of a computer. It didn't pick up any sound either.
...
I know it sounds obvious, but did you plug a known good working mic into the sound card to see if it worked? You may have a fried mic but then again the mic input on the sound card might be switched off or its gain turned way down. Likewise, how are the camera's audio input settings? Could you have an attenuator in the camera switched on and the recording level turned way down?

Is the plug on the mic a TS or a TRS plug?
Steve House is offline   Reply With Quote
Old July 30th, 2005, 01:57 PM   #5
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Yikes, I didn't catch that it was an unbalanced mic..my head was still in the previous thread. There is still a good chance that you were saved from applying the voltage to the mic by the combination of connectors. If the XLR adapter ended in a three section plug your chances are pretty good. Here's hoping...
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply With Quote
Old July 31st, 2005, 06:52 PM   #6
New Boot
 
Join Date: Oct 2004
Location: Fayetteville, Arkansas
Posts: 15
I'm not really sure whether it's a TS or a TRS plug, or whether it ends in a three section plug (I do know that it has three prongs where it plugs into the camera), because I don't have the microphone or adapter with me at this time; they're at a friend's house.

But I'll take pictures of the whole setup, and try testing the microphone on my own sound card (which I know works), and see what you guys think.

Thanks for all the help so far.
Chris Carera is offline   Reply With Quote
Old July 31st, 2005, 08:04 PM   #7
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Chris, if you can just tell us the make and model of the mic I can tell you what you need to order from B&H or pick up from Radio Shack for about $10 to make it work with the camera. This assumes the mic is still good, which I think the odds favor.
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply With Quote
Old July 31st, 2005, 10:31 PM   #8
New Boot
 
Join Date: Oct 2004
Location: Fayetteville, Arkansas
Posts: 15
This is the microphone: the Sima SZM. It's probably not a very good one, but we figured that it would be better than the camera mounted omni-directional mic.

http://www.simacorp.com/products/ite...e173f39&id=481
Chris Carera is offline   Reply With Quote
Old July 31st, 2005, 11:00 PM   #9
Major Player
 
Join Date: May 2005
Location: Sherman Oaks CA
Posts: 255
Quote:
Originally Posted by Chris Carera
I'm not really sure whether it's a TS or a TRS plug, or whether it ends in a three section plug (I do know that it has three prongs where it plugs into the camera), because I don't have the microphone or adapter with me at this time; they're at a friend's house.

But I'll take pictures of the whole setup, and try testing the microphone on my own sound card (which I know works), and see what you guys think.

Thanks for all the help so far.
Hi Chris,

I put your question to my satellite truck engineer friend. According to him, if the mic was unbalanced and given the particular circumstances you describe; you may have damaged the mic. An unbalanced mic has no transformer and the transformer is essential for providing necessary impedence for the mic.

Also the middle "ring" in a TRS connection is the only way to accept a ground?

What do I know, just passing on what my best friend took the time to address....

My best,

Steph
Stephanie Wilson is offline   Reply With Quote
Old July 31st, 2005, 11:25 PM   #10
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Well, I spoke too soon, Chris. Even Sima's web page on that mic doesn't reveal whether it has a TRS or TS mini plug on it. We'll have to wait until you get your hands on it again.

Quote:
Originally Posted by Chris Carera
...We then tried the microphone by plugging it into the sound card of a computer. It didn't pick up any sound either...
I'll have to admit that this comment cools my optimism. I didn't catch it the first time. But we can hope.
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply With Quote
Old July 31st, 2005, 11:43 PM   #11
New Boot
 
Join Date: Oct 2004
Location: Fayetteville, Arkansas
Posts: 15
In case I have to replace this thing, can any of you help me find a good price for a new one?

I've used froogle and I've seen that B&H doesn't have it, but I'm not sure where else to look, really. I'd like to find it below eighty dollars, which might be asking too much.

Thanks for everything so far.
Chris Carera is offline   Reply With Quote
Old August 1st, 2005, 05:40 AM   #12
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,337
Buck up and try the Rode VideoMic. :)

Ty Ford
Ty Ford is offline   Reply With Quote
Old August 1st, 2005, 06:05 AM   #13
Inner Circle
 
Join Date: Oct 2004
Location: Port St. Lucie, Florida
Posts: 2,614
[QUOTE=Chris Carera]In case I have to replace this thing, can any of you help me find a good price for a new one?

I've used froogle and I've seen that B&H doesn't have it, but I'm not sure where else to look, really. I'd like to find it below eighty dollars, which might be asking too much.QUOTE]

Try this Ebay link and see if it helps you. Mic you are looking for, Sima SZM-2? $23.00 right now, with no bids. Hope that this helps.

Mike

http://cgi.ebay.com/Sima-SZM-2-Zoom-...QQcmdZViewItem
__________________
Chapter one, line one. The BH.
Mike Teutsch is offline   Reply With Quote
Old August 1st, 2005, 07:33 AM   #14
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Stephanie Wilson

Also the middle "ring" in a TRS connection is the only way to accept a ground?
FYI...
TRS stereo: tip=left, ring=right, sleeve=ground
TRS balanced: tip=signal hot, ring=signal cold, sleeve=ground
TRS unbalanced, equivalent to TS: tip=signal, ring=ground (bridged to) sleeve=ground (TRS jack to TS plug wired like this makes an unbalancing adapter)

and just to make things interesting

TRS on mono mic, compatible with stereo or mono inputs: tip=signal (bridged to) ring=signal, sleeve=ground

Here's an exercise ...

How would you wire an adapter to connect a single, mono BALANCED mic so it could be plugged into a camera mini-jack input designed for a (two channel)stereo mic, disregarding any issues surrounding phantom power?
.
.
.
XLR pin 1 -> TRS sleeve
XLR pin 2 -> TRS tip bridged to TRS ring
XLR pin 3 -> unused or TRS sleeve
Steve House is offline   Reply With Quote
Old August 1st, 2005, 09:22 AM   #15
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Quote:
Originally Posted by Chris Carera
In case I have to replace this thing, can any of you help me find a good price for a new one?

I've used froogle and I've seen that B&H doesn't have it...
If Mike's eBay suggestion above doesn't work out, I got lots of hits on Google under "Sima SZM." The going price seems to be in the $40-50 range. Here's one:
http://datavisioncomputer.com/webapp...7&cgmenbr=2000
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > All Things Audio


 



All times are GMT -6. The time now is 05:06 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network