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View Full Version : [Help Needed] SDA-SRS issues after damaged woofers



paulman592
06-28-2009, 10:19 PM
hi there, i have a pair of SDA-SRS signatures (1984/85 i believe) that I'm working on for my father. The outer pair of woofers were ALL blown, luckily i had some spare 6503 drivers from a set of SDA-CRS+ of similar vinatage. But I'm still having some issues with the quality of the sound from the cabinet. As best I can work it, there seems to be an emphasis on the more out of phase audio material (aka side guitar is more evident in front of speaker or in stereo sweet spot than center vocal).

I'm inclined to blame this on the tweeters... i'm getting some output out of the tweeters from the questionable cabinet, but not nearly as much as out of the correct one, perhaps a resistance issue? I've verified wiring, switched out amps, etc. Any suggestions? My next step was to check relative output of known good tweeters out of the good cabinet vs. possible bad ones out of the other cabinet... any ideas would be helpful.

danger boy
06-28-2009, 10:23 PM
are you using the SDA interconncect cable between the speakers? if not.. hook it up. some of the drivers may not appear to be working correctly till you have the cable connected.

it is possible that some of the drivers are wired incorrectly.. that wiring system is complex if you don't know which wires are the "Hot" and which are not.

Face
06-28-2009, 10:27 PM
What kind of amp are you using?

paulman592
06-29-2009, 08:43 AM
I'm using a pair of carver tfm-22s at the moment. once i've tested them to make sure they didn't cause the damage in the first place, i'll hook up the original amps a pair of carver phase linear 400s. the interconnect is hooked up. also, one of the tweeters is definitely louder than the other three. the three are all quieter than the known good tweeters in the other cabinet

Face
06-29-2009, 08:49 AM
How are they hooked up, one amp per speaker, or one amp on the lows, one on the highs?

paulman592
06-29-2009, 10:50 AM
they're biamped, one for lows, one for highs

OldmanSRS
06-30-2009, 07:22 PM
Some suggestions:

Momentarily connect a 1.5V battery to the speaker and observe all the woofers. They should ALL either pull in or push out. It they don't, either some are wired backwards or they are not connected, or are electrically open. The sub will move opposite of the woofers.

Remove the IC cable. Does the out of phase information collapse back into toward the center. It should.

You can also swap the crossovers between cabinets and see if the problem moves.

The tweeters are all crossed over at different frequencies so the middle one is the loudest.

Greg