Heil PR20 Dynamic Microphone Compressor / Limiters Frequency ranges and boost/cut are

Frequency ranges and boost/cut are selected by three dual-concentric switches

Class-A circuit topology for optimal reach and frequency response

the volume knob is the steering wheel

I have used just about every microphone  that is known to man

Heil PR20 Dynamic Microphone Compressor / Limiters Frequency ranges and boost/cut areThe Heil PR 20 represents completely new dynamic microphone technology designed for a wide range of professional applications such as live sound, commercial broadcast, and sophisticated recording. Its wide frequency range outperforms the tired, 30+ year old industry technology and can withstand huge amounts of SPL. The end result is a microphone that can answer the call to any application. For example, the gorgeous upper mid range makes the PR 20 the