If there are no extra letters after the C at the end of the serial numbers, it sounds like they are Vandersteen 2C
Here's the timeline, according to some notes I jotted down when collecting my 2 pairs ... (not my words - quoted from other sources)
1977 – Vandersteen Model 2 debuted
1979 – Vandersteen Model 2a
1980 – Vandersteen Model 2b
1980 – Vandersteen Model 2c - last model using perishable foam surrounds
1989 – Vandersteen Model 2ci - 1st model using butyl rubber surrounds
1992 – Vandersteen Model 2ce
The first four versions (2, 2a, 2b, 2c) are not necessarily to be
avoided, but are far more prone to have numerous age-related issues.
The main issue is that the woofer edges deteriorate and require
service. Prior to 1989 all of the woofers had flexible foam rubber
surrounds, which typically only lasted about 15 years – I doubt if there is a
single example of those four models without deteriorated foam
surrounds that would need to be replaced. With the introduction of the 1989
Model 2ci version, the flexible surrounds were changed to butyl
rubber, and all subsequent models have that surround. This accounts for the
huge disparity in resale values for models manufactured prior to 1989.
The Cabinet was taller beginning with the 2CE model, so the stands are
shorter to maintain correct height for the tweeter, etc.
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I picked up a pair of these last week. I understand there's a way to tell from the serial numbers which version they are. Mine are 46048 C and 46049 C. I'd like to have some idea as to which woofers they have and whether or not I have to worry about there being foam surrounds (I can replace them, but I don't want to pull the sock for no reason).