Does anyone know details about Polk SDA’s?

VSAT88

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#21
OK, I will take the bait...Who the hell is Amy ? LOL !! I just went back and read a bit of that paper after thinking a bit ! Now I remember who Amy is. I think I agree, Amy was the bomb.
 
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VSAT88

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#22
VR3 down ? Had no idea. Never bought from there. Too much change involved for this one. And yeah, you caught me...Supra wire.... No real comment there one way or the other but I damn sure hope I don't start hearing things in the muisic I never heard before. I quit the acid years ago and have no inclination to start back.
 

MarkWComer

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#23
Maybe they are referring to a bi-amped speaker installation or dual mono amps? Lack of a common ground could cause phase shift issues that would make the sound muddy or smeared.
There ya go! I didn’t account for those!
 

VSAT88

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#24
Have a quick look at the schematic and you will see exactly why non common ground amplifiers must not be used. The interconnect would quite effectively short the amplifiers.
 

Gepetto

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#25
There ya go! I didn’t account for those!
I have not read the entire article on the SDA speaks but it sounds like there may be some right to left speaker interconnect going on to do the subtraction work that is described. This would require a common ground to accomplish easily.
 

VSAT88

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#26
Have a quick look at the schematic and you will see exactly why non common ground amplifiers must not be used. The interconnect would quite effectively short the amplifiers. However as said above there is a way to get around all that. An isolation transformer..
 

62vauxhall

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#30
I drove back from Vancouver early. The intent of the trip was to visit people, friends and cousins, I had not seen during the six months since I left there. But driving in that traffic was more than I could bear. It is a hideous place to get around in. Living there since birth you kind of expect it but after half a year's separation, I wondered WTF am I doing here!

Once home, I unloaded those SDA-2's. Before listening, I fabricated an umbillical from some Trasparent brand speaker wire I had on hand. But the bar & pin plugs I have are not the same bar & pin plugs those speakers need. Figures.

Google searching disclosed that a blade connector and center pin from an RCA plug would do so that's what's on each end of the DIY cable. Also learned that what would have come with the speakers was 21' long so that's the length I made it.

IMG_4643.JPG IMG_4641.JPG IMG_4642.JPG

They are a very nice sounding speaker. Not extensively, but I heard SDA's years ago. I had no faith in 6.5" mid/bass drivers. My intent was to try flipping these SDA-2's ASAP but am holding off until after I've lived with them a while. I like the Infinity Kappa's I've had since new in 1994 and I'm still waiting for some capacitors that go into to the Koss CM/1030's I got a few months back.

Three pairs of large-ish speakers push the limits of available space so one pair or another will likely have to go.
 
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