I'm linking what I hear from the DHA VT-1 bass overdrive. 
But the 12V supply seems a bit of a pain, as I will have to add one power supply on my board *just* for that effect. 
 
Has anybody tried it with 9V? How does it sound? 
If 9V is ok, that would make it very attractive for me (reversing polarity is not a big deal)