Replacing the K's woofers!!

laatsch55

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#1
Two weeks was too much to put up with an intermitten woofer. One call to Bob Crites and they were shipped 4 hours later. THAT is service!!
 

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laatsch55

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Helluva an amp, getting real partial to it. Joe has recommended replacing the Zoebel network resistors on Don's board as they appear inductive. Jer says it made a big difference in sound. So the Don board in this will get the fix before it goes Doug.
 

NavLinear

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#5
Helluva an amp, getting real partial to it. Joe has recommended replacing the Zoebel network resistors on Don's board as they appear inductive. Jer says it made a big difference in sound. So the Don board in this will get the fix before it goes Doug.
Don's board is a beauty. Here are a couple of shots of the board for those not familiar with it. The two 4.7 Ohm resistors are the large large white components in the photos.

View attachment 6801 View attachment 6802 View attachment 6803
 

fitz43

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#6
Helluva an amp, getting real partial to it. Joe has recommended replacing the Zoebel network resistors on Don's board as they appear inductive. Jer says it made a big difference in sound. So the Don board in this will get the fix before it goes Doug.
Thanks. Just went and read what wikipedia had to say about Zobel Networks. I'm afraid it went over my head.
 

laatsch55

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#7
They are to protect the output section in case of highly reactive or inductive lods. Exactly how they do this is Joe's territory.


Doing exactly what the wife has requested, BREAKING THE WOOFERS IN RIGHT!!! That is 123db, IN THE SWEET SPOT!!!!
 

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laatsch55

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#8
Evidently the woofs haven't been right for quite some time, don't remember them being THIS GOOOOOOOOOOOODDDDDDDDD!!!!!!!!!
 

laatsch55

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#9

laatsch55

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#10
Doug, your amp has bben real world stress tested. The thermodiscs opened up at 220 degrees fahrenheit. Didn't have the fans on. This unscheduled test of the Phase Linear Overheat Emergency Shutdowm is complete.

No amps were hurt in the making of this test.
 

NavLinear

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#13
That's the 400 board. The 700 boards are quite a bit different Dennis. No IC. Discreet , so repairable. And the big bonus--they F&^%$# WORK!!
Lee,

I went back and looked at the photos for the 700 dc protect PCB and it is quite different than the 400 board - duh. Just call me Dumas. What I did see was that the 5 watt resistor seems to be the same for both the 400 and 700 dc protect board. Should this be of concern to me?

I've noticed the heat factor while testing the 400 - I'll have a "funny" story to tell about my ventures into the audio test world in the next day or three. As always too much fun!
 

laatsch55

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#14
The Zoebel network as the same component and value wise for the 400 and 700. Joe has recommended to Jer to replace the stock resistor with the ones on the original Zoebel. ie-- 2- 3-5 watt 10 ohms in parallel the seriesed to the .1 uf cap between the +/- speaker posts.
 

laatsch55

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#15
Looking forward to your stories, I'm starting to feel like a freak, as in "Am I the only one that f$#$'s shit up when fixing it sometimes"
 

orange

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#17
They are to protect the output section in case of highly reactive or inductive lods. Exactly how they do this is Joe's territory.


Doing exactly what the wife has requested, BREAKING THE WOOFERS IN RIGHT!!! That is 123db, IN THE SWEET SPOT!!!!
Don't forget to keep the neighbor's liquor tabs paid, remember what you did LAST TIME...without Hendrix and alcohol or bud even!:rr:
 

ksrigg

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#18
So Lee, you replaced the woofers in the KHorns? And used the CAST version...So what is your opinion of the CAST vs the STAMPED FRAME. Now ya got me wondering if I did the right thing getting the stamped. Probably should have gone cast, but I would hve had to file either the cabinet or the frames to get them to fit in the La Scalas. If there is THAT much difference in sound, I ma have to put cast in them..but I think the bottom end response in the La Scala is limited by the cabinet volume anyway, so maybe no real difference in this particular .speaker.. What is the story of the intermittent woofer? Inquiring minds...
 
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laatsch55

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#19
Soirry Sutton, just noticed this. I had the cast frames to begin withn Sutton. I think I wounded them some time ago because these new ones sound a lot better.
 
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