Lon is quite correct:
If you simply have Speakers, Super Zen & Source (minimalist system) adding a CSP does add some lower end weight & authority to the overall presentation. In my case I listen to Blues, Blues Rock and Classic Rock in a large room and adding the CSP2 did not entirely solve the issue of many recordings sounding unacceptably thin and edgy.
On the other hand back when I had 120 Solid State Watts per Channel the same recordings sounded thin and edgy then also. So solving the thin & edgy issue based on my experience is not about watts alone but more about where to apply them. For a long time I just thought many of my CD's that came across thin & edgy were simply poor recordings. Since adding and dialing in my Mid Bass Module these same CD's have now become many of my favorites.
My theory on why one or more Subwoofers will not solve this problem: I think the brain actually connects low frequencies from 20 hz all the way up to about 200 hz based on my experience with the Mid Bass Module listening to a wide variety of music.
If you visualize a horizontal line, the left extreme representing 20 hz and the right extreme representing 200 hz. Say in this example your mains drive strong down to 50 hz so you set up a sub to handle the 20 to 50 hz range and raise the volume level in this range say +6 db. At some point the brain senses the abrupt change in level around the 50 hz point and says no good.
In my case I added the Mid Bass Module raising the volume level say +6 db in the 50 to 200 hz range "Sweet". Then when I introduce the sub at +6 db the entire range (20 to 200 hz) is at the same level "Sweeter". At some point if you continue raising the volume level it just becomes obvious there is too much Bass and you just back it off a bit. So the Mid Bass Module is adjustable for any room and or taste.
Most music just does not have a lot going on below 50 hz. However once you hear the Mid Mass Module in action you will have a whole new appreciation for what level of detail is revealed in the 50 to 200 hz region. So as I've stated in other threads here if I could only have one (Sub or MBM) hands down it would be the MBM first. The MBM adds 85% of the Magic and the Sub the last 15%.
Unfortunately when most of us hear the word "BASS" it immediately brings back memories of a friends system with poorly integrated Sub set a a volume that shook the windows and just sounded awful. The Mid Bass Module does none of this. This excerpt from one of the few professional reviews online states things better than I can:
Quote:"While this combination is relatively new to my reference system, it has been transformative. The combination of isolating and carefully presenting mid-bass frequencies (50-150Hz) through the mid-bass modules, and the superb performance of the VTF-3-Mark III true sub, has re-drawn my system in much larger and more substantial frame. The user ability to tailor these frequencies for room and source material adds a new dimension to the enjoyment of music, most especially that which may have come in a bit thin and threadbare. I don't care what the cognoscenti say about subs and audio, the slightly dry nature of the Hsu units, coupled with their flexibility and musicality add more to the experience of listening to music than you can possibly imagine without hearing them for yourself"
As Lon pointed out I was comparing the Positive Effect of a CSP2 relative to the Positive Effect of the Mid Bass Module in my system in a relatively large room. Comparing the two the Mid Bass Module has a much bigger positive impact. A welcome effect is a very full bodied musical presentation at low to moderate listening levels as well. With efficient speakers and a Mid Bass Module the Super Zen is no longer limited to near field listening in a small room.
As stated earlier in this thread I'm in the process of re-evaluating the effect of the CSP2 in my system with the Mid Bass Module. My impressions so far over the past few days is that there are subtle but worthwhile improvements in the mid to upper frequencies. The test will be when I remove the CSP2 in a week or so to see if I miss it ???