Connecting an XLR-terminated lav to a Sennheiser G2 wireless kit at DVinfo.net

Craig Irving · December 13th, 2007, 08:26 AM

Hi everyone, I know this is probably a basic question and presumably an obvious answer, but my ECM77B terminates in an XLR connection, yet the Sennheiser G2 kit I'm using requires a mini-jack connection obviously.

I figure all I need is an XLR --> Minijack cable to go into the transmitter, but going through the forums here I've been concerned about impedence matching, etc. etc.

Is it better to just use the supplied lavs that come with the Sennheiser G2? Obviously they're not going to be as good, but I suppose it's easier than having the subject walk around with the DC-78 power supply in his pocket, and a transmitter on him, and a big XLR --> Minijack cable.

The subject will be giving a lecture, so that's a lot of junk to walk around with.

Any advice?

Bill Ravens · December 13th, 2007, 08:43 AM

B&H has a 3.5mm minijack to dual XLR(left and right) adapter.

Steve House · December 13th, 2007, 08:52 AM

Is your mic hardwired to the power supply or is there a connector? You mentioned the DC-78 power supply but isn't that to supply power to mics equipped with the 4-pin mini connector?

Craig Irving · December 13th, 2007, 09:23 AM

Sorry guys. You're absolutely right. I read over the brochure too quickly. There's no model number for the power supply it's just integrated. I made a mistake in assuming the model number for it was the DC-78, but that appears to be a completely different accessory.

This one is a regular 3-pin XLR connection (XLR-3-12C type connector).

My best guess is that I'll need this:
http://www.bhphotovideo.com/c/produc...gled_Male.html

Bill Ravens · December 13th, 2007, 09:49 AM

yes, that's the right one. Sennheiser usually provies one with the G2.

Craig Irving · December 13th, 2007, 09:56 AM

I believe they provide a male XLR to go back from the receiver into the camera (which I'll also be using).

Greg Bellotte · December 13th, 2007, 12:21 PM

i think you'll find that the XLR to mini cable in that link might not work very well. the sennheiser transmitter input has bias voltage to power the plug in lavs. some models (500 series) even have three conductor input jacks and operate as mic or line depending how you wire it. in any case, your sony ecm has the power module at the end of the lav wire, right? using a regular XLR to mini cable, the bias voltage may interfere with the audio only signal that comes out of the sony XLR. (on the other hand-it might work. feel free to try it won't hurt anything)

the correct mic input cable from sennheiser is the CM-1.

http://www.bhphotovideo.com/c/produc...one_Cable.html

it is pretty pricey for what it is. if you are handy with soldering irons, you can build one pretty cheap. the key is to use a small capacitor to block the bias voltage from getting to your microphone. this arrangement works very well.

other options include getting lavs that are already wired for use on the G2 transmitter. in this case the mic is terminated in a mini-plug and the capsule powers from the transmitter bias voltage. no extra junk to carry. :-)

Bill Ravens · December 13th, 2007, 12:57 PM

oops! you're right Greg. Page 43 of my Senn EW100 manual shows the following xmit connector assignments:
Tip +
Ring NC/Gnd
Sleeve -

Craig Irving · December 13th, 2007, 01:09 PM

Hmmm that's too bad. Cause I'm only borrowing the G2. I would hate to have to buy a cable that is only specific for the Sennheiser in case I buy different wireless kit down the road. Maybe I should just use the lavs that come with the Sennheiser for times that I absolutely need wireless.

Jeffery Magat · December 13th, 2007, 01:37 PM

Quote:

Originally Posted by Craig Irving

Hmmm that's too bad. Cause I'm only borrowing the G2. I would hate to have to buy a cable that is only specific for the Sennheiser in case I buy different wireless kit down the road. Maybe I should just use the lavs that come with the Sennheiser for times that I absolutely need wireless.

That, or just go to Trew Audio and rent. :P

Craig Irving · December 13th, 2007, 01:46 PM

Good idea. I'll give them a call. For some reason I didn't figure they would rent out a specialty cable like that.

Hsien Yong · December 13th, 2007, 08:04 PM

Hi Craig,
I would recommend using the lavs supplied with the Sennheiser G2 kit. You don't have to get a special cable and it's alot lighter for the subject to walk around with.

December 13th, 2007, 08:26 AM	#1
Craig Irving Major Player Join Date: Jun 2006 Location: Toronto Posts: 539	Connecting an XLR-terminated lav to a Sennheiser G2 wireless kit Hi everyone, I know this is probably a basic question and presumably an obvious answer, but my ECM77B terminates in an XLR connection, yet the Sennheiser G2 kit I'm using requires a mini-jack connection obviously. I figure all I need is an XLR --> Minijack cable to go into the transmitter, but going through the forums here I've been concerned about impedence matching, etc. etc. Is it better to just use the supplied lavs that come with the Sennheiser G2? Obviously they're not going to be as good, but I suppose it's easier than having the subject walk around with the DC-78 power supply in his pocket, and a transmitter on him, and a big XLR --> Minijack cable. The subject will be giving a lecture, so that's a lot of junk to walk around with. Any advice?

December 13th, 2007, 08:52 AM	#3
Steve House Inner Circle Join Date: Mar 2005 Location: Hamilton, Ontario, Canada Posts: 5,742	Is your mic hardwired to the power supply or is there a connector? You mentioned the DC-78 power supply but isn't that to supply power to mics equipped with the 4-pin mini connector? __________________ Good news, Cousins! This week's chocolate ration is 15 grams!

December 13th, 2007, 08:43 AM	#2
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	B&H has a 3.5mm minijack to dual XLR(left and right) adapter.

December 13th, 2007, 09:23 AM	#4
Craig Irving Major Player Join Date: Jun 2006 Location: Toronto Posts: 539	Sorry guys. You're absolutely right. I read over the brochure too quickly. There's no model number for the power supply it's just integrated. I made a mistake in assuming the model number for it was the DC-78, but that appears to be a completely different accessory. This one is a regular 3-pin XLR connection (XLR-3-12C type connector). My best guess is that I'll need this: http://www.bhphotovideo.com/c/produc...gled_Male.html

December 13th, 2007, 09:49 AM	#5
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	yes, that's the right one. Sennheiser usually provies one with the G2.

December 13th, 2007, 09:56 AM	#6
Craig Irving Major Player Join Date: Jun 2006 Location: Toronto Posts: 539	I believe they provide a male XLR to go back from the receiver into the camera (which I'll also be using).

December 13th, 2007, 12:21 PM	#7
Greg Bellotte Major Player Join Date: Sep 2005 Location: SLC, UT Posts: 291	i think you'll find that the XLR to mini cable in that link might not work very well. the sennheiser transmitter input has bias voltage to power the plug in lavs. some models (500 series) even have three conductor input jacks and operate as mic or line depending how you wire it. in any case, your sony ecm has the power module at the end of the lav wire, right? using a regular XLR to mini cable, the bias voltage may interfere with the audio only signal that comes out of the sony XLR. (on the other hand-it might work. feel free to try it won't hurt anything) the correct mic input cable from sennheiser is the CM-1. http://www.bhphotovideo.com/c/produc...one_Cable.html it is pretty pricey for what it is. if you are handy with soldering irons, you can build one pretty cheap. the key is to use a small capacitor to block the bias voltage from getting to your microphone. this arrangement works very well. other options include getting lavs that are already wired for use on the G2 transmitter. in this case the mic is terminated in a mini-plug and the capsule powers from the transmitter bias voltage. no extra junk to carry. :-)

December 13th, 2007, 12:57 PM	#8
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	oops! you're right Greg. Page 43 of my Senn EW100 manual shows the following xmit connector assignments: Tip + Ring NC/Gnd Sleeve -

December 13th, 2007, 01:09 PM	#9
Craig Irving Major Player Join Date: Jun 2006 Location: Toronto Posts: 539	Hmmm that's too bad. Cause I'm only borrowing the G2. I would hate to have to buy a cable that is only specific for the Sennheiser in case I buy different wireless kit down the road. Maybe I should just use the lavs that come with the Sennheiser for times that I absolutely need wireless.

December 13th, 2007, 01:46 PM	#11
Craig Irving Major Player Join Date: Jun 2006 Location: Toronto Posts: 539	Good idea. I'll give them a call. For some reason I didn't figure they would rent out a specialty cable like that.

December 13th, 2007, 08:04 PM	#12
Hsien Yong Regular Crew Join Date: May 2004 Location: Singapore Posts: 111	Hi Craig, I would recommend using the lavs supplied with the Sennheiser G2 kit. You don't have to get a special cable and it's alot lighter for the subject to walk around with.