Topic: mic damping modifications

[mdogbucket]

Just wondering if applying damping material to some of the metal reflective surfaces around the capsule of a mic is a good idea to improve sound. 

Any recommendations about where to apply damping material and where to avoid? 

[datbrad]

I have run my mics clamped within a cluster of other mics countless times, and I have not felt that there were any reflections from the other clamps, or mics that I could hear in the final recording.

I have seen photos of acoustic foam between mics and flat surfaces that were used on stage for live sound reinforcement, or in a studio setting, but have never seen or heard of anyone wanting to do this for concert taping.

Any chance you could explain what situation you are specifically asking about, and what problems you think are audible that damping material may solve? Then, it might be easier to answer the question.

[mdogbucket]

I am actually referring to modifying the mic internally.  Applying damping material to internal reflective metal parts that cause diffraction around the diaphragm. 

My background is high end audio and many loudspeakers use special foam or cork or other damping materials around tweeters and on the baffle of the speaker.  My thinking is that sound is bouncing off of all the sharp metal surfaces in a microphone (especially cheap Chinese mics like mine) can negatively effect the sound.

I know that Michael Joly modifies the metal surrounding the capsule on many mics by machining it round and smooth to reduce diffraction.  But it seems this could be accomplished more easily and possibly more thoroughly with strategic placement of damping material.
 

[Church-Audio]

I am actually referring to modifying the mic internally.  Applying damping material to internal reflective metal parts that cause diffraction around the diaphragm. 

My background is high end audio and many loudspeakers use special foam or cork or other damping materials around tweeters and on the baffle of the speaker.  My thinking is that sound is bouncing off of all the sharp metal surfaces in a microphone (especially cheap Chinese mics like mine) can negatively effect the sound.

I know that Michael Joly modifies the metal surrounding the capsule on many mics by machining it round and smooth to reduce diffraction.  But it seems this could be accomplished more easily and possibly more thoroughly with strategic placement of damping material.
 

You always have to look at the obsorbsion coeffeciant of the materal you are using.. You could use fabric or a materal to dampen out a notch in a frequencey response.. Part of what some companies do is they us a phase plug infront of the capsule to direct the sound and filter or boost certain parts of the spectrum Earthworks does this as well as comapanies like Audio Technica. I use a materal in the back of my ca-14 mics to act like a difuser thats part of the reason why my mics sound the way they do. We have to be careful because anything you add to the front of the capsule will change the sound for better or worse. So its very importaint to have acurate measurement capabilities in order to see the changes that you are making to the capsule in real time. Thats how I did it.

Chris

[phil_er_up]

THanks chris for that detailed answer. I wonder how your CA14 worked and you gave us more info. THanks

-p