SDA Cable

For the OP....IF it has a pin/blade connection....use the RCA cable.

Blade/Blade.....ebay probably best bet.

Well, in the case of a pin/blade connection......and your choices are

A. Connect the with an RCA cable (you might have to shave the collar)

Or

B. Listen to the speakers with no cable

I’ll take what’s behind door number one, Monty.

I’ve done it. Many others have done it.....I’m pretty sure Polk Audio suggested it as a work around.....and nobody has suffered any ill effects

TroyD wrote: »

Well, in the case of a pin/blade connection......and your choices are

A. Connect the with an RCA cable (you might have to shave the collar)

Or

B. Listen to the speakers with no cable

I’ll take what’s behind door number one, Monty.

I’ve done it. Many others have done it.....I’m pretty sure Polk Audio suggested it as a work around.....and nobody has suffered any ill effects

The "ill effects" would be a reduction in SDA volume (and clarity?) due to excess resistance in the RCA cable conductor. It'd "work" but not be "right". I'm thinking that Polk used 16- or 18-gauge wire in the SDA cable; while the center conductor in typical RCA-terminated interconnects are thinner than that.

I'd suggest

C. Build a custom cable using speaker wire and modified RCA ends

D. Remove or bypass the OEM connector socket, install an aftermarket connection point--banana plugs, the fancy Neutrik air-tight audiophile connector body, or some other connector. This "works" no matter which style of connector Polk originally supplied on the 1C.

E. in the case of those 1Cs built with blade/blade connector sockets, spend the rest of your life looking for the "Adapter Plugs" that were once provided by Polk, but which are probably decades out-of-production. But God bless eBay, you might get lucky. (I doubt it.) Then use Option C.

Just moved into what I hope will be
my last house. Broke out my SDA-SRS’s (circa 1985) and went into a panic. No IC cable! Then big sigh of relief when I found it in a box with component cables. Now I’m ready to unbox my SDA-1C’s. . . Will there be an IC cable there? They have been in their boxes for a few years. Saw pin/blade cables on ebay $65. What would be a good cable to use for building a new one? Bought both sets new.

I used the neutrik sealed connectors on my 2A,s they work great. They also have a twist lock.

Hi Everyone. I hope this forum is still monitored. Despite my wife's protests, I am reviving my SDA-1Cs. But I cannot find my interconnection cable. I have seen the workarounds presented in the forums, but I have an additional problem that my two speakers have different interconnection cable sockets - one has the two blades and the other has the pin/blade (photos attached ignore the inadequate speaker wire, I will be upgrading it before its final set up). I bought these as floor models from the PX at Pearl Harbor in 1988 and did not realize the issue until later. To their credit, Polk sent me an entirely new cable with an adapter which, in the ensuing 38 years, I have lost. If anyone can give me advice as to how to fabricate and fit a new cable, I would be grateful

ASSUMING that these speakers really are a pair of 1Cs, and not a 1C and a 1B, for example:

At minimum, you need to connect the pin of the pin/blade connector to one or the other of the blades on the Blade/blade connector. I can't remember which blade is active on those. In their original configuration, one blade will not be connected to anything else, so you could connect the pin end, and then touch the other end of the cable to each blade on the other cabinet--the one that changes the sound is the correct one.
The factory recommended--but user-installed--fix was to connect the "dead" blade of the Blade/blade cabinet terminal to speaker-cable negative terminal. Kinda guessing that has not been done to your speakers, but all you'd have to do is connect an ohmmeter between the negative speaker terminal of that cabinet, and each of the two blades in the Blade/blade connector. If neither of them have continuity, the speaker has not been given the "factory-recommended" fix.
It's a matter of finding wire-end connectors that mate with the speaker-cabinet connectors--pin on one end of your SDA cable, blade on the other end.
The better fix is to bypass the OEM connectors, install and wire-in aftermarket connectors--the air-tight Neutriks heavily favored. Then you build an SDA cable of appropriate length with the matching Neutrik connectors.

Thank you both for taking the time to respond. You both seem to hint at the possibility that they are mis-matched speakers, one 1C and one 1B. Is there a definitive way I can determine this? I was definitely sold them as a pair of 1Cs.
@pitdogg2 : How do I determine what drivers are in the speakers?
@Schurkey I like your idea of using Neuriks and bypassing the OEM connectors. Is there any post, or can you provide me some guidance, on how I might do this? Also could you provide me with a link directing me to the exact Neuriks connectors you recommend?

pitdogg2 wrote: »

F1nut wrote: »

Early 1C's used a blade/blade cable. Both blades carried a signal.

My question to that is....
What then were the difference between the early C and the previous B model?
Drivers and caps?

I had known early C had B/b socket BUT I clearly was wrong to presume that the connection was both blades were NOT active.

I read somewhere years ago that some very early C's came in B cabinets. I have a pair of C's my Dad bought brand new. But they are in B cabinets. So they are "supposedly" C's. I'm not sure how to tell exactly if they are C's in B cabinets though.

Thanks again to everyone who has responded. The drivers were a combination of 6510/6511 so they are a pair of SDA-1Cs, as I thought I'd purchased. But I still have the problem of the mismatched interconnection sockets. I took some photos while I had the speakers open. The right speaker with the blade/blade socket seems to have a single wire that is terminated at a large coil (crossover?). The left speaker (pin/blade) joins the blade with the -ve speaker terminal. The interconnection pin wire, -ve and +ve speaker terminals are joined into a single plug and inserted into a socket on the circuit board (the blue, black and white wires). So I guess my question is: how do I configure my the cable I need to fabricate?
My guess is to join the single cable from the right speaker to the blue wire on the left?