After a bit of rooting around in the forums I've seen a couple of people mention that the first VBA400s were a little different, and had some sort of integrated compression in the circuitry. My (gold text one if you didn't gather already ) VBA seems to be a little less open when cranked then it really seems it should be compared to others I've played through, and I've played a white text one through my NV215 and it seemed noticeably more open. The things still loud as anything, but it turns into a bit of a wall of what seems like power amp distortion to me a bit to easily. I've not had a great deal of experience with valve amps, not bass ones especially, so couldn't say if it's poweramp distortion or just knackered tubes or the plethora of other things that go wrong with valve amps. Obviously the thing could maybe just do with a decent service, however I'm just a bit curious now I've seen it been mentioned. Gonna make a note of the serial number on it next time I use it though cos I'm pretty interested as in the other thread apparently there's only about 100 of them or something.