My Polk SDA-1C's are finally home with ME!

Auraka

avguytx wrote: »

Edit: On page 28 of the SDA Compendium is says..."Some of the first SDA 1C speakers used the same cabinet style as the 1B (using up old parts again?). Some of the first SDA 1C's also used a blade/blade interconnect cable than a pin/blade cable." Ok. That makes sense. WHat about the crossovers? Were 1C's a "board style" like some of the larger ones or were they more the terminal cup style?

DarqueKnight's SDA1C thread shows what the more recent crossover version looks like, post rebuild with larger caps.

My post here shows by serial number what point the crossover change occurred.

The re-use of older cabinets came in the form of the studio version, which look like the 1B's (the black 1C set I have).

DarqueKnight

avguytx wrote: »

Sooo....does that mean someone "added" the tops and bottoms to the speakers? Were there ever "in betweeners"? Like a hybrid of sorts between models? I know being a rep for various lines, I've seen that happen before during a transition.

Some SDA 1B owners wanted the new cabinet style of the SDA 1C, but they did not want to sell their 1B's. They just wanted to move the parts from their 1B's into a 1C cabinet. Polk sold the 1C cabinets for $700. I considered buying new cabinets for my 1B's, but I decided to remodel my 1B cabinets instead (for considerably cheaper than $700). I discuss my 1B cabinet modification here:

SDA 1B Cabinet Modification

From your pictures and the description of your crossover, it appears that you have 1C cabinets and drivers with a 1B crossover and SL-3000 tweeters. Simply adding the stock oak end caps to the stock 1B cabinets would not work because the 1B cabinet is narrower and deeper than the 1C cabinet.

avguytx wrote: »

Edit: On page 28 of the SDA Compendium is says..."Some of the first SDA 1C speakers used the same cabinet style as the 1B (using up old parts again?). Some of the first SDA 1C's also used a blade/blade interconnect cable than a pin/blade cable." Ok. That makes sense. WHat about the crossovers? Were 1C's a "board style" like some of the larger ones or were they more the terminal cup style?

The 1C used a single "board style" crossover rather than the two board crossover of the 1B. See this thread for pictures of the 1C crossover:

Improvements to the SDA 1C

I am not aware of it ever being done, but the 1B crossover boards could be adapted to use the 1C crossover parts. However, I would think that the extra work involved in doing this would negate any savings brought by using up old parts...but...maybe not. It is very easy to verify which crossover you actually have. The 1C and 1B crossovers used different parts. Just match up what you have to one of the schematics.

avguytx wrote: »

The mid/woofers in mine are the MW6510's and MW6511's, too. (I pilled them all out to check) So that jives with the book. The SDA 1B's show to have 4) MW6509's in them with the SL-2000 tweeters. Interesting.

Well, we know from the SL-3000 tweeters and tweeter resistors that one or more of the previous owners had a sense of adventure and some "surgery" was done. Hopefully you can track down the previous owner(s) to find out exactly what was done and why. Here's another quote from page 25 of that sage old Compendium:

"Frequently, a seller will offer a pair of SDA’s for sale without knowing for certain what version they have. Sometimes they think they know which version they have but they are unaware of the sometimes subtle changes from one version to the next. Compounding this difficulty is the fact that some owners have engaged in inappropriate “upgrades” by swapping out drivers and tweeters."

Buyer beware.

avguytx

Great....why can't anything be simple!?!?!? WHy can't I just get a normal everyday paid of speakers that are "factory"? lol Even my Monitor 10B's had awkward drivers in them...except for the tweeters.

I need to read a little more into it but what about which mids are "dimensional" versus "stereo"? Mine are correct in relation to the diagram for the 1C's. 6510's are on the outside and only work with the cable connected and 6511's are on the inside and work all the time. The tweeters also work at all time. Are the B's laid out the same way with the exception of using 6509 mids?

What to do...what to do.

Edit: (again)

I got an email back from the original owner about these and will be getting the paperwork for this. See below...

Good eye on the dome tweeters! I had completely forgotten about this, but the store where I bought the SDA's told me they were upgrades (and included a couple of brochures on the SRS TL's with the SDA Instruction Manual). I'll send you all this material as well as the purchase receipt. At the time I thought this was all very nice, but the only thing I really cared about was how good they sounded. Hope you enjoy them!

This is a new twist...lol

DarqueKnight

avguytx wrote: »

Great....why can't anything be simple!?!?!? Why can't I just get a normal everyday pair of speakers that are "factory"?

Sorry, most folks are hoarding those "normal" SDA's.

avguytx wrote: »

I need to read a little more into it but what about which mids are "dimensional" versus "stereo"? Mine are correct in relation to the diagram for the 1C's. 6510's are on the outside and only work with the cable connected and 6511's are on the inside and work all the time. The tweeters also work at all time. Are the B's laid out the same way with the exception of using 6509 mids?

Yes. All SDA's have the dimensional drivers next to the outside edges of the speakers.

avguytx wrote: »

I got an email back from the original owner about these and will be getting the paperwork for this. See below...

Good eye on the dome tweeters! I had completely forgotten about this, but the store where I bought the SDA's told me they were upgrades (and included a couple of brochures on the SRS TL's with the SDA Instruction Manual). I'll send you all this material as well as the purchase receipt. At the time I thought this was all very nice, but the only thing I really cared about was how good they sounded. Hope you enjoy them!

Wow. If I understand this correctly, you bought these from the original owner who bought them from an authorized Polk dealer? The question that now comes to mind is whether the dealer did this "modification" or were these some speakers that the dealer took on trade in?

I have some difficulty believing that an authorized Polk dealer would modify a brand new pair of SDA's in this way, even if a customer specifically asked for it. The pre-modified trade-in scenario seems more likely to me.

This is getting good.:)

avguytx

Stay tuned for further details! Don't you just love the excitement? It will be cool to see the receipt of where they were bought and what was done to them. I emailed him back to dig for a little more information.

I'll tell you, these DO sound good, though. I am listening to some "Journey - Captured" (Live) on vinyl and on the drum solo (side 3), it is AWESOME. Ok. Side 4 now..."Lovin, Touchin, Squeezin". I love it when my wife and kids are gone for a little while. lol The 3000's still seem a little more "tame" than the 2000's. But, for some things, that's a good thing. On vinyl, I have to turn the treble on the C-1 up a little.

Oh....LOVE the Compendium BTW. Thanks very much for a great book!

madmax

DarqueKnight wrote: »

Yes. All SDA's have the dimensional drivers next to the outside edges of the speakers.

Except for one model of 2.3's.

This is kinda cool (the tweeter upgrade) if yours had a store upgrade that was recommended by polk. Never heard of that before.

madmax

DarqueKnight

madmax wrote: »

Except for one model of 2.3's.

The 2.3's also have the two dimensional drivers along the outside edges in addition to one bass line source woofer above and below the dimensional drivers.

The 2.3TL moved the bass line source drivers to the inside edge leaving only the two dimensional drivers on the outside.

avguytx

Here was the latest email back about those tweeters....

I didn't have anything to do with the upgrade on the tweeters. They were supposedly a special order for a customer in Austin who ended up not buying them. I had gone through an arduous search for just the right sound and had just about given up when I came across the SDA's.

So, he IS the first owner but apparently whatever dealer in AUstin, TX at the time had some sort of thing going on. Pretty wild. So they were bought from a dealer like this. Interesting once more...

madmax

DarqueKnight wrote: »

The 2.3's also have the two dimensional drivers along the outside edges in addition to one bass line source woofer above and below the dimensional drivers.

The 2.3TL moved the bass line source drivers to the inside edge leaving only the two dimensional drivers on the outside.

I guess I COULD be wrong. Let me check the compendium.

avguytx

Earlier in the thread I was talking about the interesting wiring on the left channel versus what the "book" says on them. I've attached a picture of the left channel inside wiring for all to see. Check out the top right mid. If black is positive, why do BOTH terminals get a positive cable! lol I figure they might have had a shortage of some white wire and put the little white tag on the (-) side to mark it. There is enough wire on some of those mids to get them out of the cabinet about 18" each! I had to tie them up some because they were (audibly) rattling on the passive.

Still sound very good with the resistors taken off the tweeters. I'm curious to see what the difference is (to my ears) in the SL-2000's versus the SL-3000's that are currently in there. I have a pair coming from a fellow Polkster (thanks!) soon. Then, I'll most likely go ahead and order the RD0194's as well. It never hurts to have some spare tweeters around. I'm going to dissect the crossover tonight and get a list together of the parts I need for rebuilding them and may or may not rewire the cabinets with different wire. I don't see where it would make a "huge" difference for that last little run of wire. I have good wire to the speakers from the Carver amp (free Esoteric).

DarqueKnight

I would not run the SL3000's without the resistors. The DC resistance of the SL2000/RD0194 is 7.5 ohms. The DC resistance of the SL3000/RD0198 is 5.6 ohms.

A forum member tried replacing the SL2000's in his SRS's with SL3000 and it caused his amp protection circuitry to trip.

avguytx

Too late! They've been off since Saturday night and so far, so good. I've played them "reasonably" loud with my Carver M-1.0t and nothing ever happened. Of course, it was never distorted. I may have made the LED's jump to the 4th level or so at peak listening levels. 90% of the time it's at average to low volume. I will have the SL-2000's in in a week or so to evaluate and may buy the RD0194's for the sake of having. I'll call Ken or Helen tomorrow.

Thanks!

schwarcw

avguytx, Congrats and good luck on your SDA-1's! Thanks for posting all that's going on with your SDA-1's. We all can learn from this. Polk did some funny things. I buy into Jesse's "Maryjane in the house" during assembly theory:D

Seriously, keep us advised of your expereince. In the end you'll be an expert on these babies! Enjoy your new SDA's and start reading up on the crossover and SDA interconnect upgrade. These are in your future:D

Good luck!