Hello
The designer of these speakers was agut by the name of Bob Menzies. Tetrasound was based out of Calgary Alberta Canada.
The pair that you probably have are charcoal grey and retailed for 3200.00 canadian. They also made professional line that were for musicians night clubs etc. The only difference was the number of tuning rods, and the way they were tuned. Yes tuning rods that are installed in each set, if you take out a driver you will see them. The power handling on them is 300 watts rms. They were built with Mission drivers, and each speaker driver was electronically matched to its cabinet mate. Unfortunately the world wasn't ready for tetrasound and their technology, and they disolved in the late 90s. You enjoy your very rare set of loudspeakers.
Bill