Can I ask for recommendation, if choosing only one module, g1 or b1, for U12 is better choice. I like bass quantity nearest to v6s
Thanks
OK, as a former owner the V6-Stage (made universal) and a current owner of both the A12 (made universal) and the U6, maybe I can help some.
As far as modules are concerned I have the MAM, S1 and B1 (no G1 at this point).
First off I pulled out the notes I wrote up comparing the V6-Stage and U6, then I listened to the U6 without modules - just my fingers over the module port (which seems very much like the V6-Stage). Having refreshed my memory as best possible I then cycled between the moduleless (is that a word?) U6 and the A12 with the different modules multiple times.
Since you specifically mentioned bass I picked a couple of well recorded tracks with that in mind. The first is a track by my favorite indy/pop/folk girl band that has a closely mic'ed kick drum, and Daft Punks Loose Yourself to Dance.
A couple of points before my thoughts on the modules.
1) This was quite a bit harder than I expected. While both are clearly related, there are enough differences to make direct comparison difficult. Looking forward to the start of the football season I'll liken the U6 to the younger brother who is an All-State high school running back. He is highly regarded and a very capable player of the game. And then we have the A12, who is his big brother and also a running back. Though in this case he's a nationally ranked player at the college level. He is bigger, stronger and more powerful than his younger sibling. Stronger, and yet faster, more agile and quicker to react - in all respects he is a more complete player. So while the bass of the V6-Stage is quite accomplished, the A12's bass is stronger, more detailed, and faster (yet with a more natural decay). This degree of difference holds true for the mids & highs as well. I repect the V6-Stage/U6 for it's cohesive, coherent and lifelike presentation. Same for the A12, just to a greater degree - overall a more complete player. Thus, regardless of the modules used, the A12 bass doesn't directly compare to that of the V6-Stage/U6.
2) If you are a fan of the V6-Stage I suspect you'll be quite happy with the A12!
Back to your question. To my ears the bass of the B1 is closer in nature to the V6-Stage/U6 than the S1.
That said, the MAM is my favorite, as the most accomplished of the three. So my suggestion would be to get the B1 to start - with the realization the MAM is well worth buying down the road.
-Eric