I came across a good deal on an SVT-IIP. This little preamp (rack size but not very deep) is pretty old- at least 15-20 years and I think it is supposed to be the preamp from SVT II non-pro. I plugged it into the Return on my Bass 400's FX loop and dialed around on it. Tonewise... this has a ton of built-in low end voicing, the kind that rattles windows and sustains forever. Controls are straightforward, it does not have a gain/drive just a volume. On low volumes (~50%) it runs pretty clean, no noise or hum. If I have the "volume" around 75%-100% things begin to fuzz out, not sure if it is OD beacuse it sounds more like radio static with no definition. I don't believe this pre is supposed to really do overdrive. The graphic EQ sometimes randomly cuts in and out and when the "fuzz" tones occur, the EQ light dims out (kind of strange). I haven't spent that much time with this unit, but kind of noticed some volume cutting out types of issues the entire time (maybe just the graphic EQ). Any idea how to correctly investigate or fix these basic issues? I want to give this piece a little bit more of a chance. I popped the hood and it has two Chinese made "SLM Hot Rods" 12AX7's and one that is just made in China.