I had never heard about these, I read a thread about them, watched some youtube vids and bought one within 18 hours.
Solid Mahogany, Piezo pick up and REALLY fat plastic-y strings
It is an awful lot of fun but also a serious instrument once plugged in. I play DB regularly and have an NS5 for when I cannot get the DB there. I am considering retiring the NS5, the Ubass sounds just as good for the kind of heavier dull thud gut type of sound I like.
I have gigged it twice since taking delivery. one full on Jazz quintet and this morning in Church. It needs fairly careful EQing (just like a DB with a pick up). Obviously everyone thought it was hilarious when I took it out. They stopped laughing when I plugged it in. There is an awful lot of LF going on.
The strings are very slightly tacky, you cannot do a triplet ghost note drag down to a lower note in a jazz stylee, but using some natural oil from the side of my nose made things a lot smoother. You cannot do a side to side vibrato. It just does not work.
Does it sound like a full-on DB? Obv not. Does it have that sort of DB-esque low-mid, air-shifting heft? Yes.
Do I look like someone carrying a Viola when it is in it's case? Yes. You cannot have everything.
[url="http://www.youtube.com/watch?v=vNPx6RS8PiM"]http://www.youtube.com/watch?v=vNPx6RS8PiM[/url]