Portable Field Mixer/Preamp Help at DVinfo.net

Pat Sherman · October 18th, 2005, 08:29 AM

Hey All,

I started this thread sorta in the Sony Forum for some specific camera stuff. So now I move to hear for the serious audio folks.

Anyways, here's my current dilema. I have a Sony PD-170, Sennheiser EW112 G2P Wireless Lav setup and the shotgun mic on board.

My question revolves around line-level and the senn reciever. Currently I have to up the AF out to +12 in order for the camera to even move the DB meters. Sennheiser tells me I need to turn the AF out down to at least zero or below as uping it will not make it equal to a true line level out and it will distort the audio. Which I have noticed.

So here's my question, should I just scrap the audio features of the camera and take my mic to a preamp/field mixer and then to a portable DAT or Minidisc recorder? I notice that even line level on my Sony with nothing plugged into the XLR ports I notice noise through the headphones. So while the camera is out of warranty and not wanting to pay Sony's labor rates. So while recording the audio offboard(seperate) I would probably want to generate timecode to the audio recording for sync purposes..

I'm just inquiring about the best possible setup or solutions, and let me rephrase best my meaning low to medium budget so maybe not the best of the best. Some have recommend the Sound Device MM1 and a few others out there.

Jacques Mersereau · October 18th, 2005, 12:36 PM

Quote:

Originally Posted by Pat Sherman

Hey All,

>Anyways, here's my current dilema. I have a Sony PD-170, Sennheiser
>EW112 G2P Wireless Lav setup and the shotgun mic on board.
>My question revolves around line-level and the senn reciever.
>Currently I have to up the AF out to +12

(What does AF stand for?) What you need to do is to make sure
that the output of the receiver is matched to the camera input.
SO, if you are sending -50db mic level, -10 db line level, or +4 db your
camera has to be set accordingly. Not all cameras have the
built in ability to be set correctly. It appears that your receiver
is outputting mic level and your camera wants line level.

>in order for the camera to even move the DB meters.
>Sennheiser tells me I need to turn the AF out down to at least zero

Right,no matter how much you try to boost mic level, it will NEVER
be line level without some kind of gain boost.

>should I just scrap the audio features of the camera and
>take my mic to a preamp/field mixer and then to a portable DAT
>or Minidisc recorder?

You could, but there are devices that can help you. FYI, most camcorders
do NOT record audio as well as a DAT or other professional recorder.
However, the PD-170 should do a decent job if properly set up.

>I notice that even line level on my Sony with nothing
>plugged into the XLR ports I notice noise through the headphones.

Well, there could be a problem or NOT. What does it sound like
when a mic IS plugged in?

>So while recording the audio offboard(seperate) I would probably
>want to generate timecode to the audio recording for sync purposes..

I have never found syncing digital audio to digital video in post to be
a problem as long as you record at 48K/16bit and the software is
set accordingly.

>Some have recommend the Sound Device MM1 and a few
>others out there.

Sound Devices makes good stuff. Beachtek too. As you said,
it depends on what you are doing, who you are doing it for and what
level of quality you can afford.

Pat Sherman · October 18th, 2005, 07:14 PM

Well it's basically for recording wedding vows as well a speakers at presentations..

Jacques Mersereau · October 19th, 2005, 08:29 AM

How are you connecting the 1/8" mini TRS unbalanced output of the receiver
to the camera?

Pat Sherman · October 19th, 2005, 03:30 PM

I am using the 1/8" to XLR Adapter that came with the Sennheiser Wireless Receiver and using the onboard included minishotgun which is also XLR.

Cody Dulock · October 19th, 2005, 03:38 PM

i hooked a minidisc portable recorder up to the soundboard at a wedding a while back through the headphones output and it worked suprisingly good. i also got audio from a shotgun mic from far away and that obviously didnt work out good at all.

Jacques Mersereau · October 20th, 2005, 06:55 AM

Mmmmmm. And using that 1/8" to XLR and with the
*camera set to mic level* you are not getting enough signal?

The signal level should be killing you
as the camera is looking for around -50dB and the receiver should be
outputting at least -12dB.

Ty Ford · October 20th, 2005, 05:49 PM

Quote:

Originally Posted by Pat Sherman

I am using the 1/8" to XLR Adapter that came with the Sennheiser Wireless Receiver and using the onboard included minishotgun which is also XLR.

Set both inputs to mic level.

Ty Ford

Pat Sherman · October 21st, 2005, 01:04 AM

Ok.. Let me make sure I understand this..

I am using a Sennheiser EW112 G2 wireless camera mount receiver and using the matching transmitter..

I input it from 1/8" to XLR with a sennheiser included cable for that conversion. So even though it's a receiver I should set the input to MIC instead of line-level.

I can go from -30db to +12 on the AF OUT. So with setting it to MIC I for sure want to be in the negative numbers then for the PD170?

I was just under the impression that receivers such as this is for the line-level selector and mic's are for direct connected mics.. But I am more than happy to understand it further.. So anything I should watch out for? Anyone else have this combo kit?

Ty Ford · October 21st, 2005, 04:42 AM

I think you got it.

Wireless mic receivers may put out line and/or mic, depending on how they are designed.

They use more juice to push line level, which can shorten battery life.

If your receiver isn't capable of supplying the line level that the camera wants, there's nothing wrong with feeding the camera with mic level.

Yes, you'll want to scale back the output of the receiver so it doesn't overdrive the mic input of the camera.

Gain staging (setting the right input and output levels at each stage) can be tricky. If the transmitter mic input is turned up too much, loud voices will distort the transmitter. You can't reduce the distortion by turning down the receiver. If it's not turned up enough, you'll have to turn up the receiver output or camera audio input. That can increase the system noise.

Different mics have different sensitivities. When you change mics you use on your transmitter, you may have to adjust the sensitivity of the transmitter to be full but not distorted, dependng on how loud the source is.

The receiver output also needs to be adjusted so it feeds the camera properly. There's a "best" setting range for both receiver output and camera input. Check your manual for info and use your ears.

Regards,

Ty Ford

Pat Sherman · October 21st, 2005, 08:32 AM

TY,

I appreciate the response and the details.. Thanks very much.

October 18th, 2005, 08:29 AM	#1
Pat Sherman Major Player Join Date: Feb 2005 Location: DuPont, Wa Posts: 325	Portable Field Mixer/Preamp Help Hey All, I started this thread sorta in the Sony Forum for some specific camera stuff. So now I move to hear for the serious audio folks. Anyways, here's my current dilema. I have a Sony PD-170, Sennheiser EW112 G2P Wireless Lav setup and the shotgun mic on board. My question revolves around line-level and the senn reciever. Currently I have to up the AF out to +12 in order for the camera to even move the DB meters. Sennheiser tells me I need to turn the AF out down to at least zero or below as uping it will not make it equal to a true line level out and it will distort the audio. Which I have noticed. So here's my question, should I just scrap the audio features of the camera and take my mic to a preamp/field mixer and then to a portable DAT or Minidisc recorder? I notice that even line level on my Sony with nothing plugged into the XLR ports I notice noise through the headphones. So while the camera is out of warranty and not wanting to pay Sony's labor rates. So while recording the audio offboard(seperate) I would probably want to generate timecode to the audio recording for sync purposes.. I'm just inquiring about the best possible setup or solutions, and let me rephrase best my meaning low to medium budget so maybe not the best of the best. Some have recommend the Sound Device MM1 and a few others out there.

October 19th, 2005, 08:29 AM	#4
Jacques Mersereau Trustee Join Date: Mar 2002 Location: Ann Arbor, MI Posts: 1,334	How are you connecting the 1/8" mini TRS unbalanced output of the receiver to the camera? __________________ Jacques Mersereau University of Michigan-Video Studio Manager

October 20th, 2005, 06:55 AM	#7
Jacques Mersereau Trustee Join Date: Mar 2002 Location: Ann Arbor, MI Posts: 1,334	Mmmmmm. And using that 1/8" to XLR and with the camera set to mic level you are not getting enough signal? The signal level should be killing you as the camera is looking for around -50dB and the receiver should be outputting at least -12dB. __________________ Jacques Mersereau University of Michigan-Video Studio Manager

October 21st, 2005, 01:04 AM	#9
Pat Sherman Major Player Join Date: Feb 2005 Location: DuPont, Wa Posts: 325	Line-Level or MIC - Pro's con's? Ok.. Let me make sure I understand this.. I am using a Sennheiser EW112 G2 wireless camera mount receiver and using the matching transmitter.. I input it from 1/8" to XLR with a sennheiser included cable for that conversion. So even though it's a receiver I should set the input to MIC instead of line-level. I can go from -30db to +12 on the AF OUT. So with setting it to MIC I for sure want to be in the negative numbers then for the PD170? I was just under the impression that receivers such as this is for the line-level selector and mic's are for direct connected mics.. But I am more than happy to understand it further.. So anything I should watch out for? Anyone else have this combo kit?

October 21st, 2005, 04:42 AM	#10
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	I think you got it. Wireless mic receivers may put out line and/or mic, depending on how they are designed. They use more juice to push line level, which can shorten battery life. If your receiver isn't capable of supplying the line level that the camera wants, there's nothing wrong with feeding the camera with mic level. Yes, you'll want to scale back the output of the receiver so it doesn't overdrive the mic input of the camera. Gain staging (setting the right input and output levels at each stage) can be tricky. If the transmitter mic input is turned up too much, loud voices will distort the transmitter. You can't reduce the distortion by turning down the receiver. If it's not turned up enough, you'll have to turn up the receiver output or camera audio input. That can increase the system noise. Different mics have different sensitivities. When you change mics you use on your transmitter, you may have to adjust the sensitivity of the transmitter to be full but not distorted, dependng on how loud the source is. The receiver output also needs to be adjusted so it feeds the camera properly. There's a "best" setting range for both receiver output and camera input. Check your manual for info and use your ears. Regards, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

October 18th, 2005, 07:14 PM	#3
Pat Sherman Major Player Join Date: Feb 2005 Location: DuPont, Wa Posts: 325	Well it's basically for recording wedding vows as well a speakers at presentations..

October 19th, 2005, 03:30 PM	#5
Pat Sherman Major Player Join Date: Feb 2005 Location: DuPont, Wa Posts: 325	I am using the 1/8" to XLR Adapter that came with the Sennheiser Wireless Receiver and using the onboard included minishotgun which is also XLR.

October 19th, 2005, 03:38 PM	#6
Cody Dulock Major Player Join Date: Sep 2004 Location: arlington, texas Posts: 420	i hooked a minidisc portable recorder up to the soundboard at a wedding a while back through the headphones output and it worked suprisingly good. i also got audio from a shotgun mic from far away and that obviously didnt work out good at all.

October 21st, 2005, 08:32 AM	#11
Pat Sherman Major Player Join Date: Feb 2005 Location: DuPont, Wa Posts: 325	TY, I appreciate the response and the details.. Thanks very much.