Topic: Is this distortion from overloaded mics? Can it be analyzed?

[Carrera2]

It sounds like it could be the mics but it also sounds like it could be a problem with room acoustics or some sort of resonation how were the mics mounted?

The room acoustics were nasty.  Loud band, sound system that the front man described as being not quite as good as your car stereo.  Loud, wore my Etymotic ear plugs throughout.  I confirmed with a much more seasoned taper that the room acoustics there are nasty, particularly for all high decibel bands.  Mics were worn in Kangol hat.

Also what were your levels like going to your recorder?

According to Audacity, only one oscillation barely peaked throughout the entire recording.

Interesting need more facts about where and how you captured this recording where you were in relation to the sound system and how you mounted your mics.

• SP CMC-4 > SP 12v BB > R-09 line in
  
• I was seated 12-15 feet from the right bank of the PA.  Smallish size dinner club and bar.

• Mics were headworn in Kangol hat.

I *REALLY* APPRECIATE ALL THE FEEDBACK HERE FOLKS!  THANKS FOR TAKING THE TIME.

AlanK

[Humbug]

I hear no distortion either, but my ears really aren't as good as some of you guys.

However, looking at the waveform, there is a slight bias to -ve, which (in my experience) indicates a dying battery in a battery box, and does affect the recordings clarity.

I could be wrong though.

As I'm sure other people will have pointed out / you've read here, AT853 mics + 2 wire battery box will distort at high levels.

Cheers

Humbug

[Church-Audio]

I hear no distortion either, but my ears really aren't as good as some of you guys.

However, looking at the waveform, there is a slight bias to -ve, which (in my experience) indicates a dying battery in a battery box, and does affect the recordings clarity.

I could be wrong though.

As I'm sure other people will have pointed out / you've read here, AT853 mics + 2 wire battery box will distort at high levels.

Cheers


Yah that could be it! a dead battery I looked at it as well the negitive side was doing some strange stuff. Good call.


Chris Church


Humbug

[Carrera2]

However, looking at the waveform, there is a slight bias to -ve, which (in my experience) indicates a dying battery in a battery box, and does affect the recordings clarity.

In this case, fresh battery.

As I'm sure other people will have pointed out / you've read here, AT853 mics + 2 wire battery box will distort at high levels.

Yes, thanks.  I am going to use a three-wire set-up to minimize the mic distortion possibilities of these mics in the future.

[Karl]

I didn't put two and two together, that the CMC-4 and AT-853 is the same mic.  Echoing what was said above, that distortion is definitely your mics brickwalling due to a loud concert.  Those mics will work best with phantom power, but when that's not availabe the 3 wire batt box is a good way to go.  I have successfully used an 18V batt box to overcome those distortion issues with those mics.  Those are some really sensitive mics, which can be really good for some situations, but they get fickle in high SPL situations.

[Church-Audio]

I didn't put two and two together, that the CMC-4 and AT-853 is the same mic.  Echoing what was said above, that distortion is definitely your mics brickwalling due to a loud concert.  Those mics will work best with phantom power, but when that's not availabe the 3 wire batt box is a good way to go.  I have successfully used an 18V batt box to overcome those distortion issues with those mics.  Those are some really sensitive mics, which can be really good for some situations, but they get fickle in high SPL situations.

18 volts is really pushing it for these mics and your on the edge of blowing them up. I would suggest that its not bias voltage issue its a mater of having the mics modded so that they handle the extra spl. A lot of people think if you add more voltage you reduce the distortion that's actually not true.

Chris Church

[Alchemy]

For what it's worth, I heard the distortion first go around- and I'm only using the cheap V150s. It's slight but definitely apparent. Just to give you an idea...

[Karl]

I didn't put two and two together, that the CMC-4 and AT-853 is the same mic.  Echoing what was said above, that distortion is definitely your mics brickwalling due to a loud concert.  Those mics will work best with phantom power, but when that's not availabe the 3 wire batt box is a good way to go.  I have successfully used an 18V batt box to overcome those distortion issues with those mics.  Those are some really sensitive mics, which can be really good for some situations, but they get fickle in high SPL situations.

18 volts is really pushing it for these mics and your on the edge of blowing them up. I would suggest that its not bias voltage issue its a mater of having the mics modded so that they handle the extra spl. A lot of people think if you add more voltage you reduce the distortion that's actually not true.

Chris Church

Well, I heard directly from Chris from Sound Professionals that they did some 18V testing with those particular mics.  And I have made it through a few concerts without frying those mics.  I would not, however, recommend testing 18V with mics unless you want to take that risk.

I think with some mics, adding voltage would not reduce distortion, but with other mics it will.  With the 853's, distortion is definitely reduced. 

[Church-Audio]

I didn't put two and two together, that the CMC-4 and AT-853 is the same mic.  Echoing what was said above, that distortion is definitely your mics brickwalling due to a loud concert.  Those mics will work best with phantom power, but when that's not availabe the 3 wire batt box is a good way to go.  I have successfully used an 18V batt box to overcome those distortion issues with those mics.  Those are some really sensitive mics, which can be really good for some situations, but they get fickle in high SPL situations.

18 volts is really pushing it for these mics and your on the edge of blowing them up. I would suggest that its not bias voltage issue its a mater of having the mics modded so that they handle the extra spl. A lot of people think if you add more voltage you reduce the distortion that's actually not true.

Chris Church

Well, I heard directly from Chris from Sound Professionals that they did some 18V testing with those particular mics.  And I have made it through a few concerts without frying those mics.  I would not, however, recommend testing 18V with mics unless you want to take that risk.

I think with some mics, adding voltage would not reduce distortion, but with other mics it will.  With the 853's, distortion is definitely reduced. 

I have actually measured the difference between 5 volts and 10 volts it was less then half a percent of distortion. Not exactly worth bothering with. 18 volts will eventually break down the fet in your mics and destroy them.

Chris Church