SDA-1A questions.... Hmmmmmm

b2sc

I recently picked up a beautiful pair of SDA-1As while out of town and had them shipped back to my home. Unfortunately, UPS beat one of them up a bit (dinged the corners) but worse, they must've dropped one hard because upon arrival, 2 bass drivers were siezed and 1 tweeter was non functioning.

I removed the bad drivers, and, low and behold, both bass drivers and 1 of the 2 tweeters had the magnet assemblies separated from the speaker frames and were laying inside the cab!! I've got UPS coming out to inspect the speakers next week but in the meantime, I did replace the 2 woofers w/Polk replacements ordered thru Polk and I replaced the tweets w/the Peerless units. The Peerless units sound great, BTW.

Ok, so once I replaced the drivers (hopefully I'll be reimbursed by UPS, I did buy 4 new tweets so they'd all match) and everything sounds great although I'm somewhat disappointed in the bass response. I thought the SDA had a much more pronounced lower end. I'm powering these w/an Adcom 555 putting out 325wpc so power isn't an issue. My other set of speaks are B&W CDM7 SEs and the bass is much stronger w/the B&Ws which really suprised me.

So I'm wondering if I may have rewired a drivcer out of phase when I reinstalled them. I did the battery check to check phase and all the "stereo" drivers are in phase but I don't know how to check the phase of the dimensional driver. Any thoughts?

Also, I've been driving these guys hard for a week (are those my speakers distorting? Nope, just my ears :-) w/no ill effects until today, after a long, loud session, I turned it down a bit and within a minute I heard a loud pop come from the left speaker.

Damn... All the stereo drivers were dead on the left speaker, just the SDA drivers were operating. When I tweaked the balance control to the left, not a sound at all from the speaker while if I went right, the right speaker was functioning just great.

I checked the 2 fuses, they checked fine w/a DVM. I then tried my B&Ws and they were fine so I knew the amp wasn't a problem. Hooking back up the SDAs, they were fine (whew..)

So...I've seen the fusable links on the rear of the speaker, do these SDAs have thermal protection internally also? <obviously>

Thanks for allowing me to rant for a while...

F1nut

I believe that just the tweeters have thermal protection. For answers to your other questions....call Polk. They will be glad to help.

hoosier21

The Polk drivers should have + an - marked or at least + marked with a red dot, when checking your wiring for the 6.5" drivers, Polk used black for the + and white for neg., and some of the drivers have two blak wires but one has a little white piece of tape.

One channel shutting down, then coming back has to be your amp went into a protection mode of some sort, Polk used a fuse link to protect the tweeter and that could reset, but the 6.5" driver do not have such, they would have blown and died, but not come back to life.

But what do you mean by "I replaced the tweets with Peerless"? From Polk or from somewhere else? what model.

b2sc

Yes, I did wire the black leads to the terminals w/the red dots so phase should be correct on all drivers.

You're probably right about the amp going into a protect mode which I didn't think about. It did take a minute for me to shut the amp down to switch leads from the Polks to the B&Ws and it did have time to reset itself. Thanks for the suggestion

As far as the replacement tweeters, check your email.

RuSsMaN

Mag's knocked CLEAN off...been there, still there actually on some RTA8's.....mag's floating around in the cab, and 1 of them was actually shattered into several peices.....

Hope it all works out for you... Which Peerless did you buy, the one at PE/Madisound?

Larry Chanin

Perhaps the attached file may be of use to you.

Ken Swauger faxed me these diagnostic tests to check the proper functioning of various SDA speakers.

I've retyped them so others can read them. You should be able to open the document with Microsoft Word.

I hope this helps.

Larry

har_navalta

Thanks Larry for the diagnostic tests to check the proper functioning of various SDA speakers it's a big help for me too.

Anyway how's your AudioControl Bijou, mine is still in the box
because of my recent move and also because I still don't have any room to set up a Home Theater. I just finished cleaning my unfinished basement and I don't know if my SDA's will perform properly to the unfinished basement.


Har

Larry Chanin

Hi Har:

Rather than going off-topic here, might I suggest you join this thread:

Equalizer for DTS/Dolby Digital

Thanks.

Larry

PolkClyde

Larry Chanin wrote: »

Perhaps the attached file may be of use to you.

Ken Swauger faxed me these diagnostic tests to check the proper functioning of various SDA speakers.

I've retyped them so others can read them. You should be able to open the document with Microsoft Word.

I hope this helps.

Larry

IT won't open for me here