SDA-1's

[TnBilly]

I recently purchased on epay an original set of SDA-1's - the 82 vintage (1780 & 1781). With the exception of one tweeter cap that's been replaced they "appear" to be original and in working order. I've replaced the posts as the originals were a little beat and the plastic nuts gone. While doing that job I noticed the passives looked a little different than I was used to seeing, at least they're differenct than the ones on my SDA-2's. They're open in the back of the cone for one thing and they have a much more "styrofoam" appearance whereas my sda2's have a black covering over the small end of the "cone". Anyone else that has a set of these willing to compare notes with me? Thanks

[nadams]

Can you post pics of them, so we can see what you're talking about?

[F1nut]

Perfectly normal, they should be different as they are different models from different years.

[TnBilly]

Thanks guys....

I did a little dissassemby on my sda2's and the sda1's in question. The passive on each looks for the most part the same, enough so I'm now reasonable sure the one in the "1" is stock. The only difference I can detect is the pad/cover on the front is a little thicker than the one on the "2". If I was to venture a guess I'd say that is at least in part how the resonant frequency is adjusted to compensate for the extra driver over the "2"s... wort part I found in all this is the sl1000' are now sl2000's and all the mw's are 6501's. The only thing thats says 1982 is the crossovers! I have the feeling they've had a rough life. One of the woofers made a metalic click when I pushed the passive and one of the mid's makes a little rubbing if you push it gently on one side only. If you push is squarely it seems to be okay. I'll look thru the archives and see what a good versus bad driver is supposed to be!

Ron

[F1nut]

Bingo on the PR's.

Look closer it the mid driver making the "click", probably a bad one. The mid drivers will make a scratching noise if pushed in on one side only, don't do it, push evenly.

[ND13]

Originally posted by F1nut
Bingo on the PR's.

Look closer it the mid driver making the "click", probably a bad one. The mid drivers will make a scratching noise if pushed in on one side only, don't do it, push evenly.

Yeah, and better yet, don't push on them at all once you're done exploring.;)

[TnBilly]

Thanks!

I can state without reservation the driver with the "click" was bad.. all I had to replace it with was a 6510 I'd picked up as a spare but even so my "ears" now say the bass on the left is back where it belongs and the balance if you will is there. I'm much pleased with these over the 2A's even if they are kinda a kludge. I"m thinking it would be nice to go ahead and go thru the crossovers this winter and bring them up to the newer revisions using better parts.

[hotwheelman]

Tnbilly.......where in east tn. are yoiu located?

[TnBilly]

Just outside Tellico Plains! Yourself?

[hotwheelman]

Upper east end, Bristol. Dad did some work for sperry down there when I was just a bean sprout, been a while since I was down that way.......fishing excursions would bring he and I down that way as well.:D

[TnBilly]

Interesting...... these SDA-1's I just picked up afew weeks ago came from Kingsport. I was probably bidding against some of the guys here!