I own a pair of Polk SDA-2B's that I purchased new in 1987, and I purchased a vintage pair of larger 1986 SDA SRS 2's a year ago.

I've upgraded both sets with brand new tweeters, replaced crossover components with Sonicap capacitors and Mills resistors, added DynaMat Extreme to driver and passive radiator frames prone to ringing, sealed drivers to the cabinet with Mortite caulking and crafted high quality silver cables to complete the Stereo Dimensional Array (SDA) circuit between the two cabinets.

These highly modded beauties have served me well with exceptional sound.

Are there any Polkies here at Sound Thinking?

Danger Boy is the only other one that i know of, but i dont see him around much.

i've always wanted to have Polks, just never had the opportunity. odd because they are not uncommon.

I recognize DangerBoy from Club Polk where I am very active.

The biggest problem with most vintage Polk speaker models is that they are very large and very heavy. It makes transporting them over long distances difficult so I know they are quite rare outside of the states.

I've owned some of the smaller Monitor series and bookshelves and liked all of them. Never had a chance to even hear any of the big ones, much less the opportunity to buy them. One fellow I met said he had some of the top shelf SDA's at home and was going to keep them forever he liked them so much. Just don't see them on the used market a lot.

I have a set of original 10A's in the regular mix. Good sound though the JBL L112 get the most play time. Bough them a couple years ago. Seller had shifted to a newer surround sound system that he was having second thoughts about when I picked up the Polks. He had such a tough time selling the Polks that he gave me a set of Boston Acoustics A60 for buying the Polks.

Maybe someone can tell me what the deal is with the big Polks and this special ground adapter or whatever it is? I see one guy looking for a "common ground" amplifier because his SDA's require it, I see another ad for a pair of SDA2's that include the "original interconnect cable". Do these have special amplification requirements, if so what are they and why?