Originally Posted by MK77
Most mic's for this application are what are referred to as "noise cancelling" which is a bit of a misnomer. More accurately they should be called "noise rejecting". Not sure what the specs of the mic in question are.
I'd be surprised if the mic 'muff' makes a big difference, at least not without impacting the quality of the speech pickup as well.
If the un-muffed mic is hitting its AOP, then the leather muff will drop the sensitivity back into the linear region by providing an overall attenuation.
If it is at the AOP then the speech will not be adding significantly to the overall saturated signal so you will also have issues with not enough dynamics for a good squelch break when speaking as well as poor quality speech. Of course, the leather muff reduces the overall dynamic range since the mic noise floor will not move, but we are well above that.