The new amp, which I am sure is stellar, was handmade and will only be serviced by Metropolis Amps. Nothing came from Ampeg but the name. And no disrespect to Jess Oliver, but it seems that every time a new amp comes out bearing the name "B-15," it's nothing short of revolutionary. The basic idea of a circa 30 watt, 6L6 based power stage with a Baxandall preamp came straight out of the same RCA tube manuals that also informed Leo Fender. There have been more than few articles written over the years about Oliver's suggestions for "improving" the design which have been quietly re-shaped as a larger portion of the tube bass amp market becomes more familiar with the theory behind tube circuitry. Some of the original suggestions such as a cheap plug-in solid state rectifier and a four ohm speaker instead of eight can actually be dangerous to the amp!
The original B-15N has been through many iterations. One I have right now is mid 70's model wth cathode bias, (and it came that way stock) which is not supposed to even exist! I still keep up my BP subscription and their "technical" reporting has become even more laughable and obviously ad driven. I suppose that it's inevitable that ad money and a soft economy will obviously lead to less objectivity in product reviews from mags like that, but it's still sad. I have that issue, and it is good, but then again, very few of their product profiles barely even scratch the surface enought to disclose if it wasn't now. Even in subtle ways, like describing artist rigs, when the player says he uses a vintage SVT onstage, BP puts a graphic of a currently produced SVT CL in the profile, implying they're the same.