SDA 1C - No SDA "spread" with Cable

RDK006

Hey Guys -
Long time listener, first time caller here.
Been a Polk fan for over 20 years now, but a few months back I finally acquired a nice pair of SDA 1Cs, with a pin/blade connector that the fella I bought them from made himself. I really have no room or need for them, but I got them cheap and I was curious about the SDA technology.
The speakers sound great, but I was unimpressed by the SDA effect; to be honest, I heard no difference. I figured there was something wrong along the chain, but hadn't had a chance to try to figure it all out until now.
Well, turns out that the homemade IC cable I got from the guy didn't work; it apparently had a short. Reading some posts here, I learned that the blade did nothing, only the pin carried a signal, so I modded an RCA cable and jabbed them in the hole... but still nothing, no noticeable SDA effect.
Any suggestions? Am I doing something wrong? What's my next step?
Thanks in advance - and have a Happy Thanksgiving!
Ray

audioluvr

Try not jabbing it in. Sometimes you have to say sweet nothing's to it first.


Sorry. Maybe tell us more about your setup

Schurkey

RDK006 wrote: »

the homemade IC cable I got from the guy didn't work; it apparently had a short. Reading some posts here, I learned that the blade did nothing, only the pin carried a signal, so I modded an RCA cable and jabbed them in the hole.

A typical RCA interconnect is going to have a microscopic conductor, which means high resistance, which means poor signal transfer.

Wouldn't hurt to verify that the SDA drivers aren't seized/frozen; and still connected electrically. Also be worthwhile to put an AC voltmeter between the socket the pin goes in, and the black speaker-wire-terminal on the back of the cabinet. With the music playing, you should have "some" voltage, more with greater volume especially bass.

treitz3

Are you using a non-common ground amplifier? The twin/blade speakers would short out the non-common ground amplifier. The pin/blade speakers don't short the amplifier, there just isn't anything coming from the SDA components.

Tom

RDK006

Amplification isn't ideal - a 150 w/ch A/V receiver at the moment - but the speakers sound great otherwise... just no SDA effect with the cable. Speakers are 6' apart and about 5-6 feet from the side walls. They're currently pulled out about 2 feet from the back wall since I've been working on them, but no difference there or when pushed back against the read wall.

Correct me if wrong, but from what I've read for the pin/spade cable only the pin actually carries a signal and does anything, so the connection itself seems pretty straightforward. If the cable's good, what else might be causing the lack of SDA? I would assume the crossover or whatever SDA-specific circuitry there might be. Is there an easy way to check/confirm this? What's the simplest way to access the crossover - by removing the passive radiator or another way? If I'm opening these up, I may take the opportunity to upgrade a few things - I know there are several long threads about doing that - but I was really hoping to solve this no-SDA issue first.

pitdogg2

Pin carries the signal. Correct

F1nut

There are a multitude of possibilities with the crossover components being the least likely.

An RCA pin is slightly smaller than the original SDA pin, so loose fitting is a problem. The SDA pin socket can be worn out and/or heavily oxidized.

Loose internal connections.

Drivers wired incorrectly. Black or blue is positive, white or green is negative. Just one driver wired incorrectly will have a negative affect.

Someone purposely rewired the speakers to disable the SDA. Crazy as it sounds there are plenty of morons that do just that.

Bottom line, you need to open them up and start checking things.

If you find something you're not sure about post a photo showing the uncertainty.

There are members here willing to help in person if you are local to them, so if you'd like that kind of help post your approximate area.