[Elecraft] Heil mic info please?

[Indy]

I have an old Heil pro-set boom mic and headfones.  I find when I hook this
mic to my K2, it has inadequate gain. I have to shout into the mic to
activate the K2 VOX.   The Elecraft Heil mic has plenty of gain.

Question:  would the pro-set heil mic benefit from some kind of connection
through a resistor (how much) from the 5 volt line???

Please reply directly as I only get the digest from the reflector

Thank you,

Fred
kt5x