Limiting/compressing solution for AT4073a at

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

All Things Audio
Everything Audio, from acquisition to postproduction.

Thread Tools Search this Thread
Old January 19th, 2005, 04:52 AM   #1
New Boot
Join Date: Nov 2004
Location: New Zealand
Posts: 19
Limiting/compressing solution for AT4073a

Hi guys,

I really need your advice......

I have a sony dsr250 camera and recently purchased an AT4073a mic for it. The AT sounds great (huge improvement over the standard sony mic!) at low to mid levels but overloads on very high levels.
Whats the best solution for this?
I mainly shoot weddings so im shooting indoor and outdoor and recording loud and quiet passages without warning.
I need a solution that is permanent (ie - i dont have to fiddle with manual levels every second shot) and doesnt compromise the sound quality of the AT.
Ive looked at several products on the net like the beachtek's for example but its all left me a bit confused.

Any help here would be greatly apreciated :)

Regards, Nathan.
Nathan Taylor is offline   Reply With Quote
Old January 19th, 2005, 05:28 AM   #2
Major Player
Join Date: May 2003
Location: St. Louis, Missouri
Posts: 936
You have two choices... you need a good limiter in the signal path... either built-in to the camera or provided by a mixer / Beachtek type device... OR you need to set both in-cam channels to run off the same mic and set ch1 for the desired level under "normal" conditions and set ch2 lower so you have a track to go to in post...
Matt Gettemeier is offline   Reply With Quote
Old January 19th, 2005, 08:08 AM   #3
Join Date: Jul 2003
Location: Burlington
Posts: 1,837
You'll first need to determine whether the overload is occuring at the mic input or afterwards at the recording level controls.
Experiment at a loud event. Turn the recording levels down until the meters are indicating a mid-range level during loud sounds. If you can still hear distortion when monitoring from the camera, then the mic is overloading the input and you'll have to use either a small amount of attenuation or a limiter in an external device like a SoundDevices MixPre. Studio1 now makes a "BeachTek" type of box that outputs on an XLR connector. (Actually they make two, but only the Pro version passes phantom power.)
You could use that as a variable attenuator depending on the loudness of your situation.
If you're not hearing distortion on loud sounds when the meters are reading mid-range, but only when they peak too high because the controls are set for a quieter passage of your event, then you could employ an internal limiter if that camera has one. I don't remember, and you may only be able to choose manual or full auto. If that's the case, then you're back to using an external limiter or set your controls for a safety channel like Matt suggested.
Jay Massengill is offline   Reply With Quote
Old January 19th, 2005, 09:54 AM   #4
Fred Retread
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
What's no doubt confusing you can be cleared up by a lesson I previously learned from Jay and have come to understand pretty well with my GL2. Its that the level meters on cams that have them don't indicate what's happening at the input. They indicate the amplitude of the signal that's being applied to the cam's analog to digital converter. That's an important thing to monitor also, because there is no "headroom" above 0 dB at that point.

I'd bet serious money that the mic is overloading the cam. The 4073 is a very hot mic, with a stronger output than other mics (e.g., the Senn ME66) already known for their ability to overload camcorder input circuits. Check the specs page in your manual and you'll probably find that the mic input expects voltage levels somewhere between -30 and -50 dB (while you're at it, see if this is adjustable at all). Anyway, the 4073's voltage is -23 dB at sound pressure levels of 94 dB (less loud than a rock band)!

The BeachTek DXA-8 with its limiters may be your best solution because it mounts to the bottom of the camera and then you can either rove around or mount the combination to a tripod. Either way, once you set it you can forget about input levels and concentrate on filming. The DXA-8 offers addtional features and benefits as well.

One more thing, though. You will need an in line attenuator like the AT8202 to bring the 4073's output down to the working input level of the DXA-8, or else you'll have the DXA-8 itself clipping loud passages and be REALLY frustrated.
"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 January 19th, 2005, 11:10 AM   #5
Inner Circle
Join Date: Jan 2003
Location: Chicago, IL
Posts: 6,609
I use a Senn ME66 so it's slightly different but I also use a PROCO -10db attenuator on the mic during the reception and it makes a hugh difference. The built in 20db attenuator is too much (IMO) and NOT using 1 can cause clipping that is beyond control. Another thing to try is set your shotgun to AGC (on that camera its really a soft limiter) on channel 1 with the 10db attenuator, and set channel 2 to manual, drop the level to about 35-50% and now you've got 2 tracks to work with. Granted while I'm using pd150's not the 250, the audio circuitry is pretty much the same and I've been using this setup for about 2 years now and the audio works very well. Prior to that I was "riding the wheel" and it was a major PITA!

For ceremonies I use the split set up, shotgun to channel 1 on AGC, grooms wireless to channel 2 on manual and then I use the 20db attenuation on that mic because its very strong. I don't use the -10db on the shotgun during the ceremony and in the last 2 years and 121 weddings I've only had 1 audio challenge and that was where the lecturn mic wasn't turned on so for the 1st few moments of the 1st readers speaking it was virtually inaudible.
Fortunately, I clip a lav to that mic and run it to my 2nd 150 so I still had good stuff. (whew)
Play around a bit with the different settings and try the attenuator. Hey for 20 bucks the worst thing is it doesn't work for you but I think it will.
BTW, use a GOOD set of headphones to monitor and learn to trust your ears!

Don B
Don Bloom is offline   Reply With Quote
Old February 8th, 2005, 04:26 AM   #6
New Boot
Join Date: Nov 2004
Location: New Zealand
Posts: 19
Hey thanx everyone for their input.

After much web searching ive decided to go with a sound devices mixpre.
This will cover all the requirements;
# xlr in and outs
# phantom power
# visual led monitors for future use with two crew shoots
# small (ish) size
# excellent limiting control

Only problem is i cant aford one right now lol so it will have to wait a few months.
If anyone has one up for sale second hand let me know...
I take it the mixpre is completely identical to the shure version except the badge or are there reasons to pay extra for the shure one?

In the meantime i will use an AT8202 inline barrel attenuator on the mic.

Many thanx to all who gave advice - u guys rock :)
Nathan Taylor is offline   Reply With Quote
Old February 8th, 2005, 07:52 AM   #7
Inner Circle
Join Date: Nov 2004
Location: Baltimore, MD USA
Posts: 2,317
You show rare wisdom with you choice to wait, save and buy the MixPre. I reviewed it years ago and subsequently bought the larger 442 when it came out because it does more things.

I don't think it's any different than the Shure version. Why not call or eamil the caps at Sound Devices and ask them. If you do, say "hi" for me.


Ty Ford
Ty Ford is offline   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

Omega Broadcast
(512) 251-7778
Austin, TX

(973) 335-4460
Mountain Lakes, NJ

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

(800) 238-8480
Glendale, 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



All times are GMT -6. The time now is 07:23 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2015 The Digital Video Information Network