Has anyone had a chance to hear these: https://www.audiogon.com/listings/lisa0a94-meyer-sound-x-10-full-range. I suspect in their time of production they were some of the best speakers available. I've heard the newer Bluehorns which are excellent. Do any contemporary speakers implement a similar technology as this:
“Normally, in designing loudspeakers, the industry works in small incremental improvements,” explains company president John Meyer, “but working with the university gave us a chance to try something completely new. They approached us with a technology based on computer-driven hydraulics [that had been] developed to help control jet fighters moving at three times the speed of sound. They thought the high-speed, multi-input servo systems they developed could be applied to loudspeakers.”
Meyer engineers took the concept and developed it into Pressure Sensing Active Control (PSAC), which places a pressure sensor-essentially a calibrated condenser microphone-in front of the woofer. The information picked up by the sensor is then sent to the PSAC comparator circuit inserted before the LF power amplifier, which compares the sensor data to the input and puts the two signals in precise alignment. The original project was designed and prototyped entirely in the digital domain, yet interestingly, a high-speed analog computer circuit was selected for the X-10 because of its real-time speed and wide dynamic range.
“Normally, in designing loudspeakers, the industry works in small incremental improvements,” explains company president John Meyer, “but working with the university gave us a chance to try something completely new. They approached us with a technology based on computer-driven hydraulics [that had been] developed to help control jet fighters moving at three times the speed of sound. They thought the high-speed, multi-input servo systems they developed could be applied to loudspeakers.”
Meyer engineers took the concept and developed it into Pressure Sensing Active Control (PSAC), which places a pressure sensor-essentially a calibrated condenser microphone-in front of the woofer. The information picked up by the sensor is then sent to the PSAC comparator circuit inserted before the LF power amplifier, which compares the sensor data to the input and puts the two signals in precise alignment. The original project was designed and prototyped entirely in the digital domain, yet interestingly, a high-speed analog computer circuit was selected for the X-10 because of its real-time speed and wide dynamic range.