Mic/Cam Incompatability? In-line attenuator/limiter question at DVinfo.net

Jesse Bekas · November 5th, 2004, 12:16 PM

Hello All. My friend gave me an Azden SGM-X awhile back for my Pansonic PV-DV851 (a camcorder with no manual audio control).

I have tried to use the mic, but it is ridiculously hot. If there is a quiet computer/air flow in a "silent" room the sound of it will be overpowering, and voices from even a few feet away are picked up as very loud, (nearly clipping).

Is there any kind of in-line attenuator or limiter with 3.5mm mini-jack IO's that I could use, and would a solution like that even work? here are the specs right out of the manuals...

Camera -
Audio Input Level {Line} - 316 mV, 10kohm or more (I think this is referring to the component audio input)
Mic Input - Mic sensitivity -50dB (0dB = 1V/Pa, 1Khz)

Microphone -
Impedance: 1.5k Ohms @ 1KHz
Max. SPL Input Level: 103dB
Signal to Noise Ratio: 65dB
Dynamic Range: 78dB
Battery Type: LR-44 - USE ALKALINE BATTERY
Battery Current: 0.5 mA

I tried to research this first and could only find optical and XLR in-line attenuators/limiters. I'd like to be able to use the mic, but if I had to buy something like a Beachtek, I might as well buy a better mic too, and that is a whole new bag of worms.

Any suggestions or ideas about the subject are welcome, and I thank all of you ahead of time for reading this and (possibly) helping me out.

David Ennis · November 5th, 2004, 03:33 PM

One idea, if you're handy, is make your own attentuator with some 1/8" connectors and a few Radio Shack resistors.

http://www.dplay.com/book/pgs2e/pads.pdf

Graham Bernard · November 5th, 2004, 04:03 PM

Just ordered a 10dB 200ohm inline XLR for £26.00 inc taxes . . I had this from Sennhieser and the suppliers of the same. http://www.canford.de/commerce/produ...oductid=20-910

Seems like good value. Tested and components and my time and frustration . . Oh, and I can then add another inline for 20dB . . . simple and quick.

Grazie

Jesse Bekas · November 5th, 2004, 11:20 PM

I'm not really handy enough to build my own attenuator, and I'm looking for something like that XLR in-line attenuator, just with mini plugs. Of course I could get the XLR one and a couple of XLR to mini adapters, but at that cost I might as well look for a used Beachtek style device. Thanks for the advice though guys, anybody else?

Oh! You know those little volume control dials they put in-line with some walkman headphones? Could I find and use something like that with a mic, or would that introduce too much noise to the system? Anybody know of these things being sold as separate in-line accessories?

Graham Bernard · November 6th, 2004, 01:39 AM

Bad Audio will only . .er . . sound quieter. You will have "hot" quiet audio. Having a volume control will only make that which is horrid - quieter.

Grazie

David Ennis · November 6th, 2004, 02:03 PM

I don't think you'll find a solution as cheap and convenient as we hope for, Jesse.

BTW, are you sure there's no mic attenuation option buried in the cam's menus? There is in my GL2.

Graham Bernard · November 6th, 2004, 04:38 PM

Yes, I've used it often on my XM2. If you go with the onboard mic, it's sweet, it works well. Try high register girls gospel choir, in full flow? If I plug on my Senni66 it is still too hot. I've been advised to use this inline attenuator by a Senni Engineer here in the UK - so, Guys that's what I'm gonna do - only for massively big . . er, hotness.

Seeyah!

Grazie

Jesse Bekas · November 6th, 2004, 07:04 PM

So what's the difference between having an attenuator in between the mic and camera vs. a volume control in between the mic and camera. I'm sure this is a ridiculous question, but I really don't get it, so please don't berate me if you answer! I kind of "got" Graham's response, but want to know the why. If the signal from the mic (which is battery powered if that makes a difference), get lowered by a volume knob before it hits the cam, how could it still clip?

Jay Massengill · November 6th, 2004, 08:32 PM

Here's a link to an attenuator cable with 1/8" connectors--

http://www.core-sound.com/attenuator-cables.html

Jesse Bekas · November 6th, 2004, 08:39 PM

Thanks a lot Jay. Just what I was looking for (I think). I'm going to try this. They have a 30 day return policy if deosn't work, so that's a good deal!

David Ennis · November 6th, 2004, 08:49 PM

It's not a ridiculous question, and no one berates anyone around here. You're right, your volume control idea would work in an unbalanced line as an attenuator, and when adjusted to equal the dB reduction of any other attenuator it would prevent clipping just as well. As you suspected in your earlier post, it's likely to be noisey because of the slider contact plus the fact that the resistive material used wasn't selected for this application.

Jesse Bekas · November 6th, 2004, 09:28 PM

Thanks Fred. I was just joking about getting berated =).

So you're saying if the mic is hot, but not automatically clipping, the in-line volume control ($15) would be better to try first before the mini-jack 20dB attenuator ($40), or are you saying that I'd probably need both?

Jesse Bekas · November 15th, 2004, 03:04 PM

Well, I got the $10 volume control and put it in-line, between the mic and the cam, and it worked wonderfully, except...even with the voulme knob at it's loudest the audio is about 6dB too quiet. I guess I could just raise it in post...

George Ellis · November 15th, 2004, 04:14 PM

I have Audio-Technica AT8202 Attenuators. They have a 10, 20, 30 switch AND are phantom voltage compatible. Some attenuators do not work with phantom voltage, so be aware. I think they are around $40 and I got mine from one of our sponsors (B&H).

Jesse Bekas · November 15th, 2004, 09:11 PM

I appreciate the repsonse, but as earlier posts said, I'm not looking for an XLR solution.

November 5th, 2004, 12:16 PM	#1
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	Mic/Cam Incompatability? In-line attenuator/limiter question Hello All. My friend gave me an Azden SGM-X awhile back for my Pansonic PV-DV851 (a camcorder with no manual audio control). I have tried to use the mic, but it is ridiculously hot. If there is a quiet computer/air flow in a "silent" room the sound of it will be overpowering, and voices from even a few feet away are picked up as very loud, (nearly clipping). Is there any kind of in-line attenuator or limiter with 3.5mm mini-jack IO's that I could use, and would a solution like that even work? here are the specs right out of the manuals... Camera - Audio Input Level {Line} - 316 mV, 10kohm or more (I think this is referring to the component audio input) Mic Input - Mic sensitivity -50dB (0dB = 1V/Pa, 1Khz) Microphone - Impedance: 1.5k Ohms @ 1KHz Max. SPL Input Level: 103dB Signal to Noise Ratio: 65dB Dynamic Range: 78dB Battery Type: LR-44 - USE ALKALINE BATTERY Battery Current: 0.5 mA I tried to research this first and could only find optical and XLR in-line attenuators/limiters. I'd like to be able to use the mic, but if I had to buy something like a Beachtek, I might as well buy a better mic too, and that is a whole new bag of worms. Any suggestions or ideas about the subject are welcome, and I thank all of you ahead of time for reading this and (possibly) helping me out.

November 5th, 2004, 03:33 PM	#2
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	One idea, if you're handy, is make your own attentuator with some 1/8" connectors and a few Radio Shack resistors. http://www.dplay.com/book/pgs2e/pads.pdf __________________ "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

November 6th, 2004, 02:03 PM	#6
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	I don't think you'll find a solution as cheap and convenient as we hope for, Jesse. BTW, are you sure there's no mic attenuation option buried in the cam's menus? There is in my GL2. __________________ "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

November 6th, 2004, 08:49 PM	#11
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	It's not a ridiculous question, and no one berates anyone around here. You're right, your volume control idea would work in an unbalanced line as an attenuator, and when adjusted to equal the dB reduction of any other attenuator it would prevent clipping just as well. As you suspected in your earlier post, it's likely to be noisey because of the slider contact plus the fact that the resistive material used wasn't selected for this application. __________________ "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

November 5th, 2004, 04:03 PM	#3
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Just ordered a 10dB 200ohm inline XLR for £26.00 inc taxes . . I had this from Sennhieser and the suppliers of the same. http://www.canford.de/commerce/produ...oductid=20-910 Seems like good value. Tested and components and my time and frustration . . Oh, and I can then add another inline for 20dB . . . simple and quick. Grazie

November 5th, 2004, 11:20 PM	#4
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	I'm not really handy enough to build my own attenuator, and I'm looking for something like that XLR in-line attenuator, just with mini plugs. Of course I could get the XLR one and a couple of XLR to mini adapters, but at that cost I might as well look for a used Beachtek style device. Thanks for the advice though guys, anybody else? Oh! You know those little volume control dials they put in-line with some walkman headphones? Could I find and use something like that with a mic, or would that introduce too much noise to the system? Anybody know of these things being sold as separate in-line accessories?

November 6th, 2004, 01:39 AM	#5
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Bad Audio will only . .er . . sound quieter. You will have "hot" quiet audio. Having a volume control will only make that which is horrid - quieter. Grazie

November 6th, 2004, 04:38 PM	#7
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Yes, I've used it often on my XM2. If you go with the onboard mic, it's sweet, it works well. Try high register girls gospel choir, in full flow? If I plug on my Senni66 it is still too hot. I've been advised to use this inline attenuator by a Senni Engineer here in the UK - so, Guys that's what I'm gonna do - only for massively big . . er, hotness. Seeyah! Grazie

November 6th, 2004, 07:04 PM	#8
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	So what's the difference between having an attenuator in between the mic and camera vs. a volume control in between the mic and camera. I'm sure this is a ridiculous question, but I really don't get it, so please don't berate me if you answer! I kind of "got" Graham's response, but want to know the why. If the signal from the mic (which is battery powered if that makes a difference), get lowered by a volume knob before it hits the cam, how could it still clip?

November 6th, 2004, 08:32 PM	#9
Jay Massengill Trustee Join Date: Jul 2003 Location: Burlington Posts: 1,976	Here's a link to an attenuator cable with 1/8" connectors-- http://www.core-sound.com/attenuator-cables.html

November 6th, 2004, 08:39 PM	#10
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	Thanks a lot Jay. Just what I was looking for (I think). I'm going to try this. They have a 30 day return policy if deosn't work, so that's a good deal!

November 6th, 2004, 09:28 PM	#12
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	Thanks Fred. I was just joking about getting berated =). So you're saying if the mic is hot, but not automatically clipping, the in-line volume control ($15) would be better to try first before the mini-jack 20dB attenuator ($40), or are you saying that I'd probably need both?

November 15th, 2004, 03:04 PM	#13
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	Well, I got the $10 volume control and put it in-line, between the mic and the cam, and it worked wonderfully, except...even with the voulme knob at it's loudest the audio is about 6dB too quiet. I guess I could just raise it in post...

November 15th, 2004, 04:14 PM	#14
George Ellis Trustee Join Date: Feb 2004 Location: Suwanee, GA Posts: 1,241	I have Audio-Technica AT8202 Attenuators. They have a 10, 20, 30 switch AND are phantom voltage compatible. Some attenuators do not work with phantom voltage, so be aware. I think they are around $40 and I got mine from one of our sponsors (B&H).

November 15th, 2004, 09:11 PM	#15
Jesse Bekas Major Player Join Date: Mar 2004 Location: Ridgefield Park, New Jersey, USA Posts: 572	I appreciate the repsonse, but as earlier posts said, I'm not looking for an XLR solution.