Azden 200ULT Wireless System - Problem/Normal?? at DVinfo.net

Go Back   DV Info Net > The Tools of DV and HD Production > All Things Audio

All Things Audio
Everything Audio, from acquisition to postproduction.


Reply
 
Thread Tools Search this Thread
Old May 27th, 2006, 07:46 PM   #1
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Azden 200ULT Wireless System - Problem/Normal??

Hello Everyone!

I finished a job in Florida recently. For that job I ended up buying the Azden 200ULT Wireless Michrophine System.

My question is for those of you that own or use the ULT System frequently, and for the audio experts out there.

I have the system that comes with the 200UPR (2) Channel Receiver, (2) 10BT Bodypack Transmitters, and (2) EX-503 Lavalier Microphones.

I had 2 hours to checkout the system before flying to Orlando. Everything seemed to work fine. I simulated some background noise and did a range check for both channels. It sounded clear with no apparent problems. In the field however I found that the system acted a bit strange.

I was in a live restaurant and there were a lot of different machines and compressors on in the background besides the noise that the customers presented.

The problem wasn't so much that I was picking up the background noise, but that it wasn't at a constant modulation. The dialog was fine, but the background/ambient noise seemed to modulate, like a very short sine wave. I would have much rather had a constant level for the obvious reasons.

This wasn't exclusive to the compressors or any other of the equipment in the restaurant either. I went outside and the traffic gave me the same effect. The dialog was great, but the background noise is distracting.

The problem wasn't RF either. To further my test I had the talent walk from inside of the restaurant outside and then into a very quiet car... all while speaking in a normal voice. Once the door of the car closed, the disturbing effect went away.

It almost sounded like a VOX system or a squelch on a radio that is just barely kicking in.

What might be the problem?

Could it be the cheap EX-503 Lavalier Microphones, or might it be the transmitters??

Any feedback is greatly appreciated as I have another shoot the 2nd of June and either have to fix this, or return it and get something different.

Thanks Guys!!
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 28th, 2006, 12:02 AM   #2
Inner Circle
 
Join Date: May 2006
Location: Camas, WA, USA
Posts: 5,513
Is the mic a cardiod? It could be that when the talent moves around, you get a variable frequency response: Sounds in-line are full, but sounds off-line are LF only. An omni mic wouldn't have the same problem.

-Jon Fairhurst
http://PoorlyProjectedPictures.com
Jon Fairhurst is offline   Reply With Quote
Old May 28th, 2006, 05:35 AM   #3
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
How are you monitoring? Were you hearing this when sending audio through the camera or could you listen to the direct output of the receiver and also hear it there? It sounds almost like an auto level control somewhere along the chain raising the gain when the talent wasn't speaking and lowering it again as the talent begins to speak. It might be as the mic goes into the transmitter, the receiver itself, or in the camera. ALC would cause the background noises to get louder when the talent isn't speaking but then as they do, the voice dominates and the background noise level goes down again as the gain is adjusted for the louder primary sound. This pumping is a characteristic of AGC and one reason for the advice to never use automatic recording level control.
__________________
Good news, Cousins! This week's chocolate ration is 15 grams!
Steve House is offline   Reply With Quote
Old May 28th, 2006, 08:23 AM   #4
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hello Jon,

The lav is an omni directional. And the effect happens when the mic is sitting on a table stationary. The effect is like someone was turning the volume up and down very rapidly, so instead of a continuous level of background noise, it is constantly changing, which of course is way more noticeable and harder to filter out.

Thanks for the feedback, it helps!

Quote:
Originally Posted by Jon Fairhurst
Is the mic a cardiod? It could be that when the talent moves around, you get a variable frequency response: Sounds in-line are full, but sounds off-line are LF only. An omni mic wouldn't have the same problem.

-Jon Fairhurst
http://PoorlyProjectedPictures.com
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 28th, 2006, 08:36 AM   #5
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hello Steve,

I agree, as I responded above, I never use automatic settings for that very reason. I like to decide when things change.

I can't monitor the mic before it goes to the camera because the line out won't power my headsets and I don't have a pre-amp, so I have to monitor it through the camera.

BUT if I plug my shotgun mic in under the same circumstances, it doesn't give me that effect, so I have a preliminary conclusion that the wireless system is at fault.

Also, this effect happens when the talent isn't involved. If the mic is solo in the environment, the effect is evident.

I'm wondering if the frequency of the environment is outside of the frequency response of the transmitter or microphone?? If so MAYBE if the environment is fluctuating, it causes an in/out of spec condition????

Thanks for the feedback, it is helpful in the troubleshooting process!

Anyone out there own one of these systems? Run it in noisy environments??

Thanks again guys !!!



Quote:
Originally Posted by Steve House
How are you monitoring? Were you hearing this when sending audio through the camera or could you listen to the direct output of the receiver and also hear it there? It sounds almost like an auto level control somewhere along the chain raising the gain when the talent wasn't speaking and lowering it again as the talent begins to speak. It might be as the mic goes into the transmitter, the receiver itself, or in the camera. ALC would cause the background noises to get louder when the talent isn't speaking but then as they do, the voice dominates and the background noise level goes down again as the gain is adjusted for the louder primary sound. This pumping is a characteristic of AGC and one reason for the advice to never use automatic recording level control.
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 28th, 2006, 09:45 AM   #6
Wrangler
 
Join Date: Oct 2003
Location: DFW area, TX
Posts: 6,108
Images: 1
Anthony,

I would also suggest getting in touch with Azden and reporting the issue to them. They may know of something you can do to eliminate the issue. At the very least, they may acknowledge that you have a faulty unit that needs to be returned.

Good luck,

-gb-
Greg Boston is offline   Reply With Quote
Old May 28th, 2006, 10:15 AM   #7
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hey Greg,

Great suggestion, I agree, in fact I have a call into them already. I left a message, but come Tuesday I will call persistently until I get a hold of someone!

I am sure they can give me great insight into the problem, but sometimes the company BSs you to avoid having to actually think, so I find these great forums as a fantastic resource to people that actually use this stuff.

Thanks for the feedback Greg!!!!


Quote:
Originally Posted by Greg Boston
Anthony,

I would also suggest getting in touch with Azden and reporting the issue to them. They may know of something you can do to eliminate the issue. At the very least, they may acknowledge that you have a faulty unit that needs to be returned.

Good luck,

-gb-
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 28th, 2006, 11:08 AM   #8
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,323
Quote:
Originally Posted by Anthony Marotti

I agree, as I responded above, I never use automatic settings for that very reason. I like to decide when things change.

SNIP

BUT if I plug my shotgun mic in under the same circumstances, it doesn't give me that effect, so I have a preliminary conclusion that the wireless system is at fault.

Also, this effect happens when the talent isn't involved. If the mic is solo in the environment, the effect is evident.

I'm wondering if the frequency of the environment is outside of the frequency response of the transmitter or microphone?? If so MAYBE if the environment is fluctuating, it causes an in/out of spec condition????
Two thoughts. Many wireless mics use companding (compression/expansion) to help improve their S/N ratio. What you are describing sounds like a shift in the compander. AND/OR the omni is picking up very low frequency sound that you can't hear and that LF sound is causing the compander to pump.

Third thought: It's broken.

In any case, call azden.

Regards,

Ty Ford
Ty Ford is offline   Reply With Quote
Old May 28th, 2006, 11:56 AM   #9
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hello Ty Ford,

I think you are on the right track with "companding" which I have never heard of before, but seems to fit the symptoms and my process of elimination to this point.

I have a call into Azden and will pursue them aggressively on Tuesday.

My worry is that this is a trait and not a bug (it works identically on both channels with every possible combination). In that case I have to find a work around or return it. This is the only 2 channel portable rig that I could find and single channel units won't do me any good.

Thanks for the info, very informative!

AM


Quote:
Originally Posted by Ty Ford
Two thoughts. Many wireless mics use companding (compression/expansion) to help improve their S/N ratio. What you are describing sounds like a shift in the compander. AND/OR the omni is picking up very low frequency sound that you can't hear and that LF sound is causing the compander to pump.

Third thought: It's broken.

In any case, call azden.

Regards,

Ty Ford
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 28th, 2006, 05:59 PM   #10
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,323
Quote:
Originally Posted by Anthony Marotti
Hello Ty Ford,

I think you are on the right track with "companding" which I have never heard of before, but seems to fit the symptoms and my process of elimination to this point.

I have a call into Azden and will pursue them aggressively on Tuesday.

My worry is that this is a trait and not a bug (it works identically on both channels with every possible combination). In that case I have to find a work around or return it. This is the only 2 channel portable rig that I could find and single channel units won't do me any good.

Thanks for the info, very informative!

AM

You will probably find that adjusting the input sensitivity of the transmitter will change the way the pumping occurs because there is a threshold above which the companding works. See if that helps.

BTW, not all compander are created equally, the Lectrosonic and some others work very well.

Regards,

Ty Ford
Ty Ford is offline   Reply With Quote
Old May 28th, 2006, 10:33 PM   #11
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hello Again TY Ford!

I am assuming two things by your statement:

"You will probably find that adjusting the input sensitivity of the transmitter will change the way the pumping occurs because there is a threshold above which the companding works."

1) When referring to the "input sensitivity of the transmitter" you mean the little adjustment on in the battery compartment of the transmitter next to the frequency selection controls.

2) By "adjusting" you mean adjusting downward.

I am going to experiment with that right now, but I did try and adjust it at one point on location. I increased and decreased it and it didn't seem to have any effect. When I lowered it all of the way, when I raised the camera gain to bing the dialog up to acceptable levels, the effect was still there. When it was increased, the effect was just louder.

I put it back to the default middle position. I don't want to crank the camera gain too much as that just adds it's own noise into the mix.

Thanks TY Ford!!
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 29th, 2006, 05:13 AM   #12
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Anthony Marotti
Hello Again TY Ford!

I am assuming two things by your statement:

"You will probably find that adjusting the input sensitivity of the transmitter will change the way the pumping occurs because there is a threshold above which the companding works."

1) When referring to the "input sensitivity of the transmitter" you mean the little adjustment on in the battery compartment of the transmitter next to the frequency selection controls.

2) By "adjusting" you mean adjusting downward.

I am going to experiment with that right now, but I did try and adjust it at one point on location. I increased and decreased it and it didn't seem to have any effect. When I lowered it all of the way, when I raised the camera gain to bing the dialog up to acceptable levels, the effect was still there. When it was increased, the effect was just louder.

I put it back to the default middle position. I don't want to crank the camera gain too much as that just adds it's own noise into the mix.

Thanks TY Ford!!
Remember you have to deal with levels are two stages with a wireless mic. First the mic itself must feed signal to the transmitter at the right level so the transmitter sends a well-modulated signal but doesn't overload or clip in its audio stages and then the receiver needs to be sending the right output level to the camera.
__________________
Good news, Cousins! This week's chocolate ration is 15 grams!
Steve House is offline   Reply With Quote
Old May 29th, 2006, 09:58 AM   #13
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,323
Was this the mc that came with the wireless system?
Try a dfferent mic. Maybe something hinky in the mic or in the way it's wired.

Ty Ford
Ty Ford is offline   Reply With Quote
Old May 29th, 2006, 10:44 AM   #14
Major Player
 
Join Date: Feb 2005
Location: Rochester, NY
Posts: 263
Hello Steve and TY,

My levels should be good at every stage, and I tried two different 503 lavs in the transmitter.

I think that after more experimentation that I can restate what I think may be happening.

When comparing the wireless system to the on camera mic, and a shotgun mic, I notice that the other two mics give me a better overall sound than the wireless system, not as much with the dialog, but with the ambient sound.

With the other two mics you hear the background noise and it sounds uniform, but looking at the meters they are fluctuating as the wireless, but not as bad.

The wireless system sounds like it is fluctuating more in the extreme so instead of a smooth wave that the other mics output, the wireless system has much deeper valleys so it sounds annoying.

The high end is equal to the other mics in level and quality, but the low side of the wave gets so low that it sounds like dropout, even if for only a millisecond or two.

I am not sure if a better mic would do the trick, I am not even sure what mics are compatible with that system.

It seems that a lot of people have purchased these systems and I can't imagine that I am that much more picky than everyone else?? Am I the only one that is imagining the use of a portable filter that would limit the floor, or some kind of location (portable that could attach next to the receiver) compression filter device?

Sorry, I have this shoot Friday and I wanted to use this system.

What do you guys think??

Thanks !!!!
__________________
AM
Anthony Marotti is offline   Reply With Quote
Old May 29th, 2006, 10:57 AM   #15
Inner Circle
 
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,323
I thnk it may also be possble that the wireless may be experiencing interference. Whare are you and what is the operating frequency of the wireless?

Go here: http://www.lectrosonics.com/service/...tionlookup.htm

Find your city and check to see if the frequency of your wireless is the same as a local TV staton.

Ty Ford
Ty Ford 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...

Professional Video
(800) 833-4801
Portland, OR

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

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

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

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 09:37 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network