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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Rick Scofield on June 22, 2016, 01:15:21 PM
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After many (7-8) years of excellent subwoofer duty, my single Growler (2008-2009 model) has unfortunately given up the ghost. I've fed it "only the best organic" 1000-ish watts from either a PV2600 or Crest ProLite 2.0 for light bottom end reinforcement for a rock/pop cover band.
Discovered this past weekend that it would no longer make any sound. Worked fine without complaint the previous weekend, and has been personally and gently handled my me.
Double checked signal chain thru other speakers and isolated the problem to the Growler. (Boooo).
After contacting Jeff at JTR and confirming there is a replacement driver available, I pulled the hatch and removed the damaged driver expecting to see obvious broken something.
To my surprise the super beefy 12" woofer appears perfectly brand new and pristine. No burnt smell, perfectly supple surround and spider. Tinsel leads appear flawless. What I can see of the voice coil poking above the gap appears to be lovely bright copper. Cone moves smoothly and silently with zero rubbing.
Ohm meter across the leads reads infinity so I must have an open somewhere.
Apparently there are no available replacement (re-coning) parts for this driver according to Jeff.
I'll "happily" order the replacement driver which, according to JTR is a newer design that handles more power, but I hate to just dump this beautiful but damaged subwoofer driver in the trash.
Is there someplace I can take this little beast that's able to carefully dissect, repair, and reassemble it? I'm 30 miles east of San Francisco.
Sage advice (or condolences) from my Labster friends is most appreciated.
-Rick
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Is it throw away because of the newer design, or was it always so? If so, then wow!
The magnet has to have value. If you have the driver spec, maybe you can find a cone to suit.
Mount the basket to your shop wall and use the magnet as a tool holder.
Sad news
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Take it to a QUALITY speaker reconer.
There are several places that it might have "opened up".
Some of these can be fixed-depending on where they are.
I used to take pride in doing those sort of repairs-without have to do a full recone.
Some times it is where the tinsel leads connects to the voice coil wire.
Removal of the dust cap and a little scrapping away at the joint can give a place to test.
But you have to know what you are doing.
And then it could a break deep inside that just "broke".
Maybe a slight defect that was in the driver since day 1 and finally broke.
It does happen.
Not all failures are due to over power.
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Take it to a QUALITY speaker reconer.
There are several places that it might have "opened up".
Some of these can be fixed-depending on where they are.
I used to take pride in doing those sort of repairs-without have to do a full recone.
Some times it is where the tinsel leads connects to the voice coil wire.
Removal of the dust cap and a little scrapping away at the joint can give a place to test.
But you have to know what you are doing.
And then it could a break deep inside that just "broke".
Maybe a slight defect that was in the driver since day 1 and finally broke.
It does happen.
Not all failures are due to over power.
Ivan, your suggestion is EXACTLY what I'm hoping for. Actually had you in mind when posting. Just gotta find a high quality repair specialist. Ideally in Northern California.
Thanks for your input!
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Ivan, your suggestion is EXACTLY what I'm hoping for. Actually had you in mind when posting. Just gotta find a high quality repair specialist. Ideally in Northern California.
Thanks for your input!
What it takes is somebody that CARES about their customers, and not just wanting to "run it down the line" and do the normal repair.
I used to do a lot of vintage jukebox and radio repairs and "putting together" (ie rigging kits) for old Western Electric speakers and such.
To me, that was part of the fun, and the challenge.
Not as much money as a full recone-but much more satisfying.
Maybe that is why my business failed-I was having to much fun and not paying attention to the business side of things.
That is why I stay away from the business side now :) I don't want to kill somebody elses business
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Maybe call A Broun Sound. Haven't dealt with them personally other than buying one of their Tone Tubby speakers but I've heard good things.
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Maybe call A Broun Sound. Haven't dealt with them personally other than buying one of their Tone Tubby speakers but I've heard good things.
Thanks Stephen, I have left them a message. Raul (I think it was he) at Third Ear suggested A Brown Sound as well.
In the meantime I ordered the replacement driver from Jeff at JTR. He has provided excellent service.
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A Brown Sound
Well shucks, A Brown let me know that they wouldn't even want to touch the driver with no replacement parts available. Maybe I'll just try removing the dust cap myself and see if I can find something simple/stupid wrong.
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Well shucks, A Brown let me know that they wouldn't even want to touch the driver with no replacement parts available. Maybe I'll just try removing the dust cap myself and see if I can find something simple/stupid wrong.
Take the dust cap off-then scrape off a little area of the glue where the voice coil wires are-not the lead in wires.
Do this on just 1 wire (your choice).
When you get to the wire-scrape off a tad of the insulation.
Now you have some points to measure DC resistance.
Measure several points, from each input terminal to the scraped part.
You may need to scrape the other wire to get a better idea if the break is in the coil itself or the connection of the lead in wires to the voice coil wires.
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Take the dust cap off-then scrape off a little area of the glue where the voice coil wires are-not the lead in wires.
Do this on just 1 wire (your choice).
When you get to the wire-scrape off a tad of the insulation.
Now you have some points to measure DC resistance.
Measure several points, from each input terminal to the scraped part.
You may need to scrape the other wire to get a better idea if the break is in the coil itself or the connection of the lead in wires to the voice coil wires.
Got the dust cap removed but no tinsel leads or other cool wires can be seen. So I peer thru the frame at the underside of the spider and that's when I see the burn mark.
Looks like I'm SOL. Replacement driver comes tomorrow. Just didn't want to toss this nice assembly.
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Got the dust cap removed but no tinsel leads or other cool wires can be seen. So I peer thru the frame at the underside of the spider and that's when I see the burn mark.
Looks like I'm SOL. Replacement driver comes tomorrow. Just didn't want to toss this nice assembly.
At this stage-I would go ahead and cut out the whole assembly.
This is to give you some information.
The burn mark you see could simply be a weak point in the coil that finally failed.
Or the coil could be "nicely roasted".
The reason for further investigation is to give you a clue as to how hard you have been driving the cabinet.
If the coil is nice and clean-then the burn mark could simply be a flaw in that particular driver.
But if it shows signs of over power, then you need to look closer at your limiter settings.
I like to use failures as "information gathering" to help me reduce future failures-if possible.
Post some photos when you get it cut out, to get some more opinions on the failure.
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At this stage-I would go ahead and cut out the whole assembly.
This is to give you some information.
The burn mark you see could simply be a weak point in the coil that finally failed.
Or the coil could be "nicely roasted".
The reason for further investigation is to give you a clue as to how hard you have been driving the cabinet.
If the coil is nice and clean-then the burn mark could simply be a flaw in that particular driver.
But if it shows signs of over power, then you need to look closer at your limiter settings.
I like to use failures as "information gathering" to help me reduce future failures-if possible.
Post some photos when you get it cut out, to get some more opinions on the failure.
Dust cap off, looking down thru the coil, former and magnet.
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in the meantime, here are the two (old on the left vs new on the right) drivers. Need to pick up some good sealing weather strip before installing the new driver.
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Apparently some increase in the Xmax. Ya think?