Original poster: "Peter Lawrence by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Peter.Lawrence-at-Sun-dot-com> Terry, (and anyone else working on SS-TC, Kennan?...) since the resonant frequence of a TC secondary seems to change w/ and w/o a streamer, have you ever considered changing the driver frequence in real time to match the secondary. -Peter Lawrence.