Paradigm Sig-4 trouble

[Rickster71]

Just found out that one of my Paradigm Sig-4's that I use for rear surrounds only has the tweeter functioning.
To make sure it wasn't the amp's rear left channel I moved it to another room and amp. Still the same.
The jumpers are tight

I just took out the crossover and don't see anything obvious.
Have to move another set of rear surrounds in to watch District-9 tonight, and try to figure this out.
I'm really surprised to have a problem, I tend to baby all my stuff.

 

[TLS Guy]

Just found out that one of my Paradigm Sig-4's that I use for rear surrounds only has the tweeter functioning.
To make sure it wasn't the amp's rear left channel I moved it to another room and amp. Still the same.
The jumpers are tight

I just took out the crossover and don't see anything obvious.
Have to move another set of rear surrounds in to watch District-9 tonight, and try to figure this out.
I'm really surprised to have a problem, I tend to baby all my stuff.

Check the woofer with your ohm meter and a battery. If the woofer is OK, then check for a bad spade connection or dry solder joint. I doubt the choke to the woofer is burnt out unless the quality of the component is complete junk. You can easily test the inductor with your ohm meter. If the low pass cap is bad, it would not prevent the woofer making sound, unless the cap was shorted and then your amp protection would kick in.

This will not take you more than ten minutes to figure out and probably less.

There is a small list of possibilities here.

 

[Rickster71]

Thanks Mark, while I still have these apart I'll make a few tests.

It turns out they are still under the 5 year warranty. I'll call my local guy where I purchased these and take a ride over; as soon as I shovel myself out of the driveway.

 

[Alex2507]

I'm still waiting for the diagnosis like you had a sick child on your hands.
Just call me when you know. The not knowing is killing me.

That 5 year warranty must be why Greg gets them. There is like a 100% chance of him launching one of his drivers into a lunar orbit through the course of 5 years. His Paradigms cringe when he moves toward the liquor cabinet.

 

[KEW]

Thanks Mark, while I still have these apart I'll make a few tests.

It turns out they are still under the 5 year warranty. I'll call my local guy where I purchased these and take a ride over; as soon as I shovel myself out of the driveway.

So, whadduhyuhknow? Did you do the battery test?
Hurry up, already! Not all of us have a life you know, lol!!!

Paradigms seem so overbuilt with their thick aluminum plates - I wonder if it is just for show or if the hidden components are to the same standard?

 

[KEW]

I'm still waiting for the diagnosis like you had a sick child on your hands.
Just call me when you know. The not knowing is killing me.

That 5 year warranty must be why Greg gets them. There is like a 100% chance of him launching one of his drivers into a lunar orbit through the course of 5 years. His Paradigms cringe when he moves toward the liquor cabinet.

Great photo, Alex.
Is that a self portrait as you are anxiously waiting for the diagnosis?
Or is it how Greg's speakers cringe as he moves to the liquor cabinet?

 

[Alex2507]

Great photo, Alex.
Is that a self portrait as you are anxiously waiting for the diagnosis?
Or is it how Greg's speakers cringe as he moves to the liquor cabinet?

That's Greg's speaker and probably the guy next door.
If I was 1/2 as nerdy my printer would work.

 

[Rickster71]

I've been looking at the crossover while I'm braising my baby back ribs for the Super Bowl party we're going to later.

Both Bass and Mid drivers passed the battery test, and a continuity test.
I have the crossover out and don't see any cold or broken solder joints.
Continuity between all wires & spades.

EDIT: I found it.
The 5-way binding post is attached to the board with a gold plated piece of metal that's bent at 90 degrees and soldered to the board. The pair that's attached to the tweeter PCB are fine. The two soldered to the Mid & Woofer PCB are cracked right at the bend. I saw this yesterday and thought it was a shadow where the solder ended.

Nothings easy; I wanted to post some pictures, can't get into my Photo Bucket account.

 

[TLS Guy]

Both Bass and Mid drivers passed the battery test, and a continuity test.
I have the crossover out and don't see any cold or broken solder joints.
Continuity between all wires & spades.

EDIT: I found it.
The 5-way binding post is attached to the board with a gold plated piece of metal that's bent at 90 degrees and soldered to the board. The pair that's attached to the tweeter PCB are fine. The two soldered to the Mid & Woofer PCB are cracked right at the bend. I saw this yesterday and thought it was a shadow where the solder ended.

Nothings easy; I wanted to post some pictures, can't get into my Photo Bucket account.

I thought you would get that nailed down fast.

 

[Alex2507]

I wanted to post some pictures, can't get into my Photo Bucket account.

You suck !!!

 

[Rickster71]

The tall white panel next to the speaker stand, is Markw's Magnepan 1.6 that he lent me for 'a while.'

 

[Rickster71]

Here is another shot of Marks Maggie next to my Sig-4

 

[KEW]

Any of you speaker gurus,
I gather those speakers have been in service for a while. What would cause the metal to break like that? It makes sense that there would be a stress concentration at the edge of the soldier joint, but it seems like it would take some vibration across the joint for a crack to form.
Do crossovers produce vibrations or is this just from vibrations in the speaker and the crossover being cantilevered out?

 

[Alex2507]

Thanks for the pic's. Hope you get that photobucket thing sorted out and continue with the speaker tour. Heaven only knows what treasures you have stored up in those rooms. I wish you had snapped a few pic's of that hockey puck maneuver but there's still a chance that you haven't done the other speaker yet.

So, what's the plan now? Fix the break? New crossover/s? New speaker/s?
Inquiring minds ...

I think I would be tempted to fix the break and continue on. Everything else has stood the test of time with those speakers. Any other course of action introduces more work and more risk IMHO.

 

[Warpdrv]

Any of you speaker gurus,
I gather those speakers have been in service for a while. What would cause the metal to break like that? It makes sense that there would be a stress concentration at the edge of the soldier joint, but it seems like it would take some vibration across the joint for a crack to form.
Do crossovers produce vibrations or is this just from vibrations in the speaker and the crossover being cantilevered out?

Looking at those pics, the only thing I can think of is that when that lead was bent it probably had a fracture in it, and it finally gave way to the vibration of the speaker playing over this amount of time.... that and installation of the nut, if it was tightened to hard, possibly putting some lateral force helped it to break loose over time.

 

[Rickster71]

Looking at those pics, the only thing I can think of is that when that lead was bent it probably had a fracture in it, and it finally gave way to the vibration of the speaker playing over this amount of time.... that and installation of the nut, if it was tightened to hard, possibly putting some lateral force helped it to break loose over time.

Warp, I agree.
There is a lock washer under the nut too, it digs into that tab when it gets tightened.

The board is only braced for the inch it's slid into the rails on the terminal cup.
I held it up and flexed the woofer PCB, it's the longer of the two. It does move right at the bend in those tabs.
That can flex anytime the speaker gets moved, like during shipping, or anytime the speaker gets moved.

A fix would be to make the gold terminals thicker, and make the slot the PCB slides into longer, to support the board along more of it's length.

 

[TLS Guy]

Thanks for the pic's. Hope you get that photobucket thing sorted out and continue with the speaker tour. Heaven only knows what treasures you have stored up in those rooms. I wish you had snapped a few pic's of that hockey puck maneuver but there's still a chance that you haven't done the other speaker yet.

So, what's the plan now? Fix the break? New crossover/s? New speaker/s?
Inquiring minds ...

I think I would be tempted to fix the break and continue on. Everything else has stood the test of time with those speakers. Any other course of action introduces more work and more risk IMHO.

Easily fixed. Just clean it up and solder a wire to the terminal ring and the other onto the board tag. Takes about five minutes.

The brass looks like dreadful Chinese goods. It looks as if there is corrosion there.

It seems the Chinese don't take the trouble to look up the formula for brass worked out at England's metallurgical research center in Birmingham back in the eighteenth century, and yes they had one back then! They developed the formula for among many other things, plumbing grade brass and admiralty brass among many other metals.

The Chinese are flooding American homes at an alarming rate. I had a failure a couple of years ago. Nothing like the right formula, and a reliable national testing agency told me there is no consistency in Chinese brass at all. They are all different and none correct and contain lead they are not supposed to.

As I have said before, it is time to close the book on China. We can and should make our own product, especially basic things like glass, rubber, brass and steel for Heaven's sake.

 

[Rickster71]

Went to see my Dealer.
Paradigm is sending me a replacement crossover; the entire assembly.
I'm going to check the other speaker, and see what that looks like.

 

[Warpdrv]

Thats an easyway to fix it as well....

Paradigm is good about replacing their broken parts....

Even though TLS is right... a simple soldering will take care of the problem.

 

[Rickster71]

Thats an easyway to fix it as well....

Paradigm is good about replacing their broken parts....

Even though TLS is right... a simple soldering will take care of the problem.

Absolutely, if they weren't under warranty I'd fix them myself.