I recently acquied Ampeg B25 cab ('ve benn told it was bought in 1969) with 70's replacement speakers Electro Voice 15R series II (200w each). As I found out there was some factory replacements for the CTS speakers over the 70s Linden/Magnavox era and there were Altecs and EV's as a factory uprages (although EVs being more or less for the V4B cab). The codes on the speakers (both) are 79629 - I don't know how can I date them. Maye 79 is the year, but the 62 is not the week... I don't see any other codes on the speaker or the cone beside the LONG serial number. The strange thing about his cab that it looks completely stock, on the top it has four little dips for rubber feet.. but on the bottom it has six big dips in the size like my 8x10 has. So, is that original? All of them look stock. Maybe they did the little holes for B25 guitar amp, and the BIG holes for v4b and so on?