Since SigmaDSP is mainly for audio processing applications, I decided to put this small topic here. I am sorry if it is a wrong place, so if moderators decide to move it somewhere, I will understand. The idea is, I need my SigmaDSP for processing ultrasonic frequencies, range 30-70Khz. The idea is, I need a good wide range speaker for these frequencies. And the idea is I can not find anything, because all the piezo tweeters have a fixed frequency at which they operate and very very narrow range, usually about 1-2Khz. When I turn to electrostatic speakers, the frequency range is much better, but there are lots of additional problems with powering them up. So could just anyone give some advice, whether there are any ultrasonic speakers with wide frequency range and small size, which I could use with my SigmaDSP?