Hey Mario: I run my memory lane at 18V with a power cord I got directly from diamond pedals, using two 9v outputs from a pp2. My valvulator has a 12V output, and I used to run my fulldrive off that. Compared to a 9V supply, I noticed the fulldrive slightly crisper - and more noticeable in the comp cut mode. Mine was a later one, with the toggles. Never tried it with a full 18 V though - so that might make even more difference. Yee haw!
Peter
Peter