I have a number of shure mic's that work quite well with our PA system. However, when I try to use them on my TASCAM 424 mkII I have to turn the gain up about as high as it will go. These are HI Z mic's and I have been told that I need an impedance matching transformer to connect them to the TASCAM. So far I have been unable to find any such matching transformer. My question is: Do these things exist and if so where can a person buy them? ANYONE HAVE A CLUE? Cap't Bob