I've been asking about these before, but since I haven't found any real answers yet I'll try again... There has to be someone here who knows something about these woofers. I'm interested in the bass versions which were used in Marshall IBS cabinets. I did some searches and found out that there is four versions in 12" / 15" sizes.
12"
S12-150 PaperEdge (cast and pressed chassis versions) LEAD
S12-150 ClothEdge (cast and pressed chassis versions) BASS
15"
S15-250 ClothEdge (cast and pressed chassis versions)
S15-250 HighSensitivity ClothEdge (cast and pressed chassis versions)
And of course there is also 8 and 16 ohms versions, so that makes total of 16 different woofers. What a mess...
I found the following codes:
S12-150 T3771 (8 ohms, 12")
S12-150 T3772 (16 ohms, 12")
S12-150 T3865 (8 ohms, 12")
S15-250 T3925 (8 ohms, 15")
S15-250 T3840 (16 ohms, 15")
That's all I know so far... So I need help to identify these woofers. If anyone could match even one of these, I would really appreciate it. I think... I THINK but I'm not sure that the 12" T3771 and T3772 are the LEAD versions and T3865 is the BASS one... But with cast or pressed chassis... I don't know. Only thing I know for sure is that the 15" ones are both BASS versions since there is no 15" LEAD available.