What SDA 2Bs' are these?

[audiobilly]

Greetings to all who stopped by!:)

I have come up with a pair of SDA 2 speakers, I think they are 2Bs'. I am trying to determine what version of SDA 2Bs' these are, and what year, 1987 or 1989. These have the pin/blade IC, SL2000 tweeter, and the typical 2 drivers and 1 12" PR. These do not have the end caps.

According to the schematics, the drivers part#'s are the same in the 87 and 89 versions. The schematics do not show a part# for tweeter in the 87 version, but do reference a SL2000 in the 89 version. All in all the 89 version of the schematics looks to be the same as the 87 version, just a better drawing, I am still looking at this to see if there is indeed a "noted" difference.

What am I missing?

Thanks Gang.

[MillerLiteScott]

Sounds like Studio 2B's.

[george daniel]

another vote for 2B studio version

[audiobilly]

OK, we can confirm the 2B version part, for the most part. Now what version 2B are they. If you look up the schematics, there are 2, 2Bs' after the BB (blade blade) version, if I am reading correctly. I am trying to find the correct schematic, so I can rebuild them. These guys are at work, so I will pull the drivers to see if they can tell me anything different to what I am reading in the schematics.

What da ya think Gang?

And thanks for the replies Scott and george

[Hamatym]

Pull out the driver's and see what they are....2B's will be (1) MW6503 & (1) MW6511 If you have those, then you have 2b"s

[gimpod]

OK, we can confirm the 2B version part, for the most part. Now what version 2B are they. If you look up the schematics, there are 2, 2Bs' after the BB (blade blade) version, if I am reading correctly. I am trying to find the correct schematic, so I can rebuild them. These guys are at work, so I will pull the drivers to see if they can tell me anything different to what I am reading in the schematics.

What da ya think Gang?

And thanks for the replies Scott and george

If there 2B's, as far as the crossovers go there the same one for all 3 versions.

[F1nut]

Pull one of the crossovers, all the values are printed on the caps and resistors.

[audiobilly]

Thanks for the replies Hamatym, gim54pod and F1 nut.

I can not find any difference from the 87 and 89 versions of the schematics, just looks like a better drawing. This looks like what I have. Like F1 says pull it apart and see what it is. I like to have an overview of "what" to expect before going in. So I am just trying to get my ducks in row.

Thanks gang!!!

[heiney9]

Thanks for the replies Hamatym, gim54pod and F1 nut.

I can not find any difference from the 87 and 89 versions of the schematics, just looks like a better drawing. This looks like what I have. Like F1 says pull it apart and see what it is. I like to have an overview of "what" to expect before going in. So I am just trying to get my ducks in row.

Thanks gang!!!

87 has blade/blade; 89 has pin/blade and an improved polyswitch other wise the x-over is exactly the same. The best way to tell is by the driver model numbers 2B's have MW6511 for the dimensional driver and MW6503 for the stereo driver.

H9

[audiobilly]

Thanks for the input H9!

All in all, the only difference in the "87 pb" drawing and the "89" drawing is the polyswitch update.