original SDA SRS problem

TooChannel

Hello everyone, new to the Forum and new to polk audio. Just scored a set of original SDA SRS's, have heard alot of good things about them so I thought I'd grab the chance to get a pair for $600.00. My problem is the sda function on the left speaker is not working, also there is one tweeter not working on the same speaker (not sure if thats the problem with the sda function) anyway I tested them from instructions i found somewhere here and when I move the balance to the right channel I get nothing from the left dimensional drivers but I do get sound from the right dimensional drivers when the balance is moved to the left. Any assistance on what else to check or direction for assistance would be greatly appreciated! By the way I am powering them with a carver TFM-22, Thanks in advance, this forum seems to have alot of very knowledgable members and have enjoyed lurking here for the last couple months

Pauly

Welcome,

You have the cable plugged into the speakers? Pin Blade or Blad Blade?

Pauly

F1nut

For starters, open the speaker and look for a loose/bad connection. Also, look for a loose/bad connection to the tweeter. It has nothing to do with the SDA function though.

That amp isn't really enough to drive the speakers properly.

Pauly

I read wrong with the SDA effect. Yeah do what Jesse says


Pauly

JohnLocke88

I just want to know where people are picking up these speakers for $600......

TooChannel

Pauly wrote: »

Welcome,

You have the cable plugged into the speakers? Pin Blade or Blad Blade?

Pauly

Yes I have the interconnect cable plugged in, It is Blade/Blade. One end of the cable was a little loose but I did a continuity test and checked OK. Am I correct in thinking since the cable connects the two speakers and one end was bad that niether speaker would have the function?

Thanks
Joe

george daniel

Joe,, I believe that you are correct in regards to the cable,, have you checked for loos connections,,ie,, you may have to go inside an nose around,, keep us posted and I'm sure others will chime in with step by step help in solving your issue--good luckcongrats on your new aquisition.

TooChannel

F1nut wrote: »

For starters, open the speaker and look for a loose/bad connection. Also, look for a loose/bad connection to the tweeter. It has nothing to do with the SDA function though.

That amp isn't really enough to drive the speakers properly.

I pulled the crossover from the left speaker and all connections looked good. I pulled out the bad tweeter and the lead connections were good but the wire from one lead that runs up the front of the frame to the diaphram is loose, not sure if it can be repaired or has to be replaced.

After reading many posts on this forum I came to realize the carver would be a little on the light side but need to get the speakers working properly before I invest in more juice.

Thanks
Joe

treitz3

Try this please. Play some music at a reasonable level and with a paper towel or toilet paper core [cardboard part] put directly up to the ear, listen to each driver individually. Note exactly what drivers are functioning and which aren't. Then swap the L&R speaker cables on the amp. Does the exact opposite thing happen?

george daniel

Hmmm,, can you swap crossovers and see if the problem follows,, you can take your speaker cables and attach them to the tweeter,and turn the volume up very slowly to determine the tweeter status,,or swap the tweeter to the other speaker.

jimmydep

I know nothing about the SDA's, but these guy's do.

Welcome to the Club.........Good luck with your problem


Jim D

TooChannel

JohnLocke88 wrote: »

I just want to know where people are picking up these speakers for $600......

I was pretty shocked myself when on saw them on local CL way up in northern NY, not alot of Hi fi nuts up here

Thanks Joe

TooChannel

Lasareath wrote: »

Welcome to Club Polk TooChannel!

F1nut has started you on the correct direction.

Do you have the black Interconnect cable plugged in?, It's the cable that plugs into that socket in the back of the speakers.

If you do not then you will not get the SDA effect.

As per your amp, F1nut is correct, that amp is way too small for those speakers. If you want to stick with Carver then you need at least (1) TFM-35X

With my 1.2TL's I have (2) TFM-35X's hooked up and I am very happy with the way they perform.

Lasareath

Hi Lasereath

Yes I have the cable plugged in and I am getting the SDA effect in the right speaker but not the left, thanks for the advice on the amps as soon as I get these monsters workig properly I will be on the hunt for more power. by the way you said you use 2 TFM-35s, is one running LFs and one running HFs?

Thanks again for the input
Joe

F1nut

I pulled the crossover from the left speaker and all connections looked good.

I should have been more specific, you need to test with a Volt/Ohm meter.

TooChannel

F1nut wrote: »

I should have been more specific, you need to test with a Volt/Ohm meter.

have a volt/ohm meter but definitely only beginner skills, is there somewhere I can get schematics and instructions on where and what to check for

Thanks
Joe

TooChannel

treitz3 wrote: »

Try this please. Play some music at a reasonable level and with a paper towel or toilet paper core [cardboard part] put directly up to the ear, listen to each driver individually. Note exactly what drivers are functioning and which aren't. Then swap the L&R speaker cables on the amp. Does the exact opposite thing happen?

Will try that and report back tommorrow. Thanks for the input, you guys are great!!

Joe

treitz3

No problem Joe. Welcome to the forum.

jimbo1421

TooChannel wrote: »

have a volt/ohm meter but definitely only beginner skills, is there somewhere I can get schematics and instructions on where and what to check for

Thanks
Joe

Hi Joe,

You can find testing procedures here: http://www.polkaudio.com/forums/showthread.php?t=85837

Also there are schematics posted in the Vintage section of the forum.

Jim

TooChannel

jimbo1421 wrote: »

Hi Joe,

You can find testing procedures here: http://www.polkaudio.com/forums/showthread.php?t=85837

Also there are schematics posted in the Vintage section of the forum.

Jim

Hi Jim

Wow great post, hoping to clear some time this afternoon and let the testing begin! A big thanks to everyone, Your assistance is greatly appreciated!!

Joe

TooChannel

treitz3 wrote: »

Try this please. Play some music at a reasonable level and with a paper towel or toilet paper core [cardboard part] put directly up to the ear, listen to each driver individually. Note exactly what drivers are functioning and which aren't. Then swap the L&R speaker cables on the amp. Does the exact opposite thing happen?

Hi treitz3

tried your test

Left speaker
sound from all tweets except #3 (which i new was bad)
sound from all main drivers
no sound from array drivers

Right speaker
sound from all drivers

When left and right cables were switched had the same results

Thanks
Joe

treitz3

Ok, now refer to post #11. We have now determined that the left speaker is the issue. Try that and then get back to us please.

Bubinga99

From what you describe, I think I'd try this:

Take out one of the dimensional drivers (doesn't matter which one for this test) from the left speaker (with speaker disconnected from the amp and interconnect cable not plugged in) and clip one of the test leads from your ohm meter to one of the disconnected wires (again doesn't matter which one for this test).

With the other lead on your meter, measure ohms to each pin of the interconnect cable input on the back of the speaker separately, and then to the + low frequency terminal on the back. Three separate measurements.

It sounds like you have an open connection internally somewhere, so this will help narrow down where to begin looking.

TooChannel

jimbo1421 wrote: »

Hi Joe,

You can find testing procedures here: http://www.polkaudio.com/forums/showthread.php?t=85837

Also there are schematics posted in the Vintage section of the forum.

Jim

Hi Jim

Followed the testing procedure

procedure #1
Got correct results on right speaker but no dimensional sound from left

procedure #2
Got correct results on right speaker but no dimensional sound from left

procedure #3

IC #2 (sm) to black rgt=0 lft=4.3
IC #1 (lg) to black rgt=0 lft=0
IC #1 (lg) to IC #2(sm) rgt=0 lft=0
IC #2 (sm) to red rgt=0 lft=0
red to black rgt=4.3 lft=4.4
IC#1 (lg) to red rgt=0 lft=0

from the results of test #2 in procedure #3 is it possible that some internal connection in the right speaker could be causing the sound problem in the left? I havent snooped around the inside of the right speaker yet

Thanks a Bunch!!
Joe

TooChannel

Bubinga99 wrote: »

From what you describe, I think I'd try this:

Take out one of the dimensional drivers (doesn't matter which one for this test) from the left speaker (with speaker disconnected from the amp and interconnect cable not plugged in) and clip one of the test leads from your ohm meter to one of the disconnected wires (again doesn't matter which one for this test).

With the other lead on your meter, measure ohms to each pin of the interconnect cable input on the back of the speaker separately, and then to the + low frequency terminal on the back. Three separate measurements.

It sounds like you have an open connection internally somewhere, so this will help narrow down where to begin looking.

Hi Bubinga99

Just want to confirm a question, do i leave the leads to the driver itself connected for this test or remove them

Thanks for the assistance
Joe

danger boy

sounds like the SDA cable connecting to the left speaker may be to loose or bad and not activating them.

try swapping the cable around and see if it follows the cable. just a thought.

Bubinga99

TooChannel wrote: »

Hi Bubinga99

Just want to confirm a question, do i leave the leads to the driver itself connected for this test or remove them

Thanks for the assistance
Joe

Joe, it's probably easiest to completely disconnect the driver (but note which wire goes to which speaker terminal) so you don't have to leave it hanging. You're looking for an extreme condition (an open circuit).

The measurement from the removed driver's wire to the B terminal of the interconnect socket (as labeled on the schematic) might give some strange readings because there is a capacitor in the path. Different meters do different things. For this measurement, do 2 measurements. Hook your meter up and read the first, then swap the meter leads and read again.

Actually, do the same (2 readings, meter leads swapped) for the other interconnect terminal, just in case your internal wiring is swapped.

chandler9a

Hi Joe and welcome to Club Polk! I too have a pair of SRS's with the same problem and have not found the problem yet. the array drivers in my right channel do not produce any sound and I have eliminated all of the possibilities you have gone through. I'm thinking it might be a crossover issue somewhere in the right channel cabinet but do not have the resources to check at this time and Polk apparently does not sell them any longer.

I also live in upstate NY and saw those for sale on CL so I'm happy someone got them who will take care of them. Best of luck with the outcome and let us know how it goes.

Chandler 9a

TooChannel

Bubinga99 wrote: »

Joe, it's probably easiest to completely disconnect the driver (but note which wire goes to which speaker terminal) so you don't have to leave it hanging. You're looking for an extreme condition (an open circuit).

The measurement from the removed driver's wire to the B terminal of the interconnect socket (as labeled on the schematic) might give some strange readings because there is a capacitor in the path. Different meters do different things. For this measurement, do 2 measurements. Hook your meter up and read the first, then swap the meter leads and read again.

Actually, do the same (2 readings, meter leads swapped) for the other interconnect terminal, just in case your internal wiring is swapped.

Hey Bubinga99

Could not determine which blade was "b" and "A" from schematic so my results will label SM (small blade) and (LG) large blade.
also LF & HF connector was in place (hope this was correct)

Pos speaker lead to SM IC blade = 1.1 ohm
Pos speaker lead to LG IC blade = nothing
Pos speaker lead to Pos LF terminal 1.2 ohm
swaping leads from meter had same results

for what its worth i did the same test with the neg. speaker lead

Neg speaker lead to SM IC blade = 4.6 ohm
Neg speaker lead to LG IC blade = nothing
Neg speaker lead to Pos LF terminal 4.6 ohm
swaping leads from meter had same results

Also from a previous post I foung recently http://www.polkaudio.com/forums/showthread.php?t=5387
I reversed the speaker wires on the right speaker (correctly working speaker) and still had the same problem with the left speaker (had high hopes though)

Thanks for the help, everyone here has been really cool to a newbie
Joe

TooChannel

danger boy wrote: »

sounds like the SDA cable connecting to the left speaker may be to loose or bad and not activating them.

try swapping the cable around and see if it follows the cable. just a thought.

Hey danger boy

Gave it a try, same problem

Thanks for the input
Joe

xsmi

Stayed in the left or moved to the right?

Bubinga99

TooChannel wrote: »

Hey Bubinga99

Could not determine which blade was "b" and "A" from schematic so my results will label SM (small blade) and (LG) large blade.
also LF & HF connector was in place (hope this was correct)

Pos speaker lead to SM IC blade = 1.1 ohm
Pos speaker lead to LG IC blade = nothing
Pos speaker lead to Pos LF terminal 1.2 ohm
swaping leads from meter had same results

for what its worth i did the same test with the neg. speaker lead

Neg speaker lead to SM IC blade = 4.6 ohm
Neg speaker lead to LG IC blade = nothing
Neg speaker lead to Pos LF terminal 4.6 ohm
swaping leads from meter had same results

Also from a previous post I foung recently http://www.polkaudio.com/forums/showthread.php?t=5387
I reversed the speaker wires on the right speaker (correctly working speaker) and still had the same problem with the left speaker (had high hopes though)

Thanks for the help, everyone here has been really cool to a newbie
Joe

From those results I think it says A is the small IC blade and B is the large IC blade. But just to double check, see if the small blade to the + speaker terminal is a short (or something under say .2 ohms).

The "nothing" reading is worth looking into. Different meters do different things when you have a capacitor in the path and you're measuring resistance. Based on the 2 meters I have, and the 2 different ways they read when there's a large capacitor, it's surprising it would read nothing (open) regardless of which way you swap the leads. So you may (I emphasize may) be on to something here. There may be an open circuit inside the speaker, somewhere between the large IC terminal and the drivers. Or, this may just be the way your meter responds to capacitors.

OK, next thing to try: with the interconnect cable disconnected, and the right speaker disconnected, hook the + left speaker wire to the + terminal on the left (broken) speaker. Hook the minus lead of the left speaker wire (this will require some rigging) into the large IC blade (B on the schematic) and see if you get sound from the dimensional drivers. I'm guessing you won't but this will eliminate a couple other things.

Assuming you don't get sound, next I'm afraid you're going to have to open the left speaker up. A good quality photo of the crossover network and the backside of the speaker wire terminals will help to point you to the next things to check.