This is the response I gave at the Hsu forum:
Dear fellow audio enthusiasts,
We are now starting to transition from the end of an old era to the beginning of a new era here at Hsu Research. The TN series, introduced in the mid-1990's, were remarkable products and very effective in achieving Dr. Hsu's goal of maximizing bass per given floorspace. They were celebrated by numerous reviewers and owners alike. One of the things we are most proud of is the fact that they helped push forward the Do-It-Yourself craze. The TN subwoofers were created based on very fundamentally sound ideas in physics, and yet were easy enough for almost anyone to build in their own home, even those with no background in physics or in engineering. The pure simplicity of the TN design, coupled with the very high performance and relatively low cost, ultimately helped lead to the creation of numerous other similar subwoofer designs based upon the same principles we have used at Hsu Research.
As a relatively small company, we have always tried to limit the number of models that we carry at any given time to as much extent as possible. This gives us more opportunity to streamline and perfect existing products. Dr. Hsu always believes in providing more for less, and in providing for the greatest good. That is why you see him focusing his efforts first and foremost on the most affordable subwoofers and speakers. We have some great ideas for the expensive and exclusive "flagship" subwoofer market, but rest assured that our primary focus moving forward will be on providing higher quality and higher output bass for as many budgets as possible.
The TN1220HO had remarkably clean output at and above 16Hz, especially based on it's size, and even performs comparably to some of the "latest and greatest" cylinder designs available today. In my opinion, the new technology that Dr. Hsu has developed will take this performance to a new level. In the past, it was arguable that the TN1220HO/TN1225HO were cleaner low bass performers than the VTF-3/VTF-2. This fact alone helped to justify their existence, regardless of the fact that the box shape is much more popular with consumers. This situation does not hold true when comparing the TN series with the upcoming VTF-HO series. The upcoming VTF-2HO has the potential to be as potent as a TN1220HO in the low bass, and the upcoming VTF-3HO has the potential to be as potent as dual TN1220HO's in the low bass, with added flexibility too.
In a sense, Dr. Hsu is helping to redefine the ported subwoofer market, again. I hope you are all excited about what lies ahead. We are definitely excited.
Sincerely,
