Mount your SM91 in your bass drum.
Internal kick drum boundary microphones have always come with a challenge to keep them reliably in place inside the kick drum. Introducing The Kelly SHU FLATZ System. It is an ideal mounting system for the Shure SM91.
The Kelly SHU FLATZ is a dedicated kick drum microphone shock-mount isolation and stabilizing platform which installs in minutes with no drilling required. The system utilizes existing tuning hardware inside the drum for attaching the included solid rubber support rings between the drum shell and the FLATZ mounting unit. What you get is an isolated platform which holds your boundary microphone in place and you can leave the microphone inside the drum during transport without the worry of the microphone shifting position or damaging the interior of your drum shell. The FLATZ platform gets the microphone up and off of the drum shell or dampening material, putting it closer to the sound source and opening up the response that you'll get from the microphone.
The Kelly SHU FLATZ Platform is made from 30% fiberglass and high-density polymer resins. Our 3 different models of Kelly SHU FLATZ are each specifically designed to accomodate the most popular of boundary microphones which are used internally for kick drum amplification. Each model has it's own set of built in features which encompass the microphone's case to hold it firmly in position. The solid rubber support ring system is as easy to install as removing and replacing 4 hardware screws inside the drum shell. Just install the system and insert the intended boundary microphone into the FLATZ platform. Now you're ready to connect to the sound system using your current means and methods.