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Blew out the woofers on my brand new speakers, need help to find the cause

sigbergaudio

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Pretty sure i didn't clip anything. However, if the speaker woofer's voice coil "bottomed out" or the voice coil banged a couple of times, is that driver considered to be permanently degraded perhaps, with respect to sound fidelity? I mean, what would the average hifi enthusiast's opinion be about such a scenario?

Bottoming out doesn't necessarily damage the driver, but it's not great either. Did you hear any mechanical noise from the drivers when you did this?
 

Doodski

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Pretty sure i didn't clip anything. However, if the speaker woofer's voice coil "bottomed out" or the voice coil banged a couple of times, is that driver considered to be permanently degraded perhaps, with respect to sound fidelity? I mean, what would the average hifi enthusiast's opinion be about such a scenario?
After a frequency sweep from the low to the highs more can be known about the woofer(s).
 
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Bottoming out doesn't necessarily damage the driver, but it's not great either. Did you hear any mechanical noise from the drivers when you did this?
Ok, that's a bit comforting. I couldn't tell you if i heard mechanical noise as I was standing by the subwoofers at the back of the room. When i realized that the speaker amp was on, i just ran straight to the front of the room to kill the amp's power.
 

rdenney

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Mechanical noise from a woofer bottoming out is not subtle. It would produce a loud rat-at-at-tat that you'd easily hear over the largely subsonic 20-Hz sine wave. If it really sounded lout at all, you probably heard healthy dose of harmonic distortion--the harmonics would at least be up where you could hear them. But clipping is more noticeably distorted, and bottoming out is obviously mechanical.

The usual damage to running out of excursion room is to deform the voice coil so that it no longer moves in the field without scraping something. It might even tear the spider, though usually the back of the speaker is more of a constraint than the front. If the speaker works as it should now, it's fine.

Rick "play music" Denney
 

fpitas

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Mechanical noise from a woofer bottoming out is not subtle. It would produce a loud rat-at-at-tat that you'd easily hear over the largely subsonic 20-Hz sine wave. If it really sounded lout at all, you probably heard healthy dose of harmonic distortion--the harmonics would at least be up where you could hear them. But clipping is more noticeably distorted, and bottoming out is obviously mechanical.

The usual damage to running out of excursion room is to deform the voice coil so that it no longer moves in the field without scraping something. It might even tear the spider, though usually the back of the speaker is more of a constraint than the front. If the speaker works as it should now, it's fine.

Rick "play music" Denney
Sometimes the wires start shedding off the voice coil from the abuse. If that happens, you'll hear that soon enough ;)
 

mhardy6647

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Sometimes the wires start shedding off the voice coil from the abuse. If that happens, you'll hear that soon enough ;)
Grizzled old audio vets like us, umm, I mean me have also seen the VCs physically distort (e.g., varnish insulation on copper VC wire bubble up) causing the VC to drag.
I have a poor EV SP12B "fullrange" twincone driver here that works but has essentially no excursion. To paraphrase Dr. Barbenheimer: It is become the World's Largest Tweeter -- Destroyer of Bass. :eek:



Even putting it in a Karlson couldn't help! ;)
 

fpitas

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dweeeeb2

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I haven’t read the whole thread but TC you are not alone. i burnt my lintons trying to rattle the house…….I now have a sub and HPF to mains
 

fpitas

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fpitas

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mixsit

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Grizzled old audio vets like us, umm, I mean me have also seen the VCs physically distort (e.g., varnish insulation on copper VC wire bubble up) causing the VC to drag.
I have a poor EV SP12B "fullrange" twincone driver here that works but has essentially no excursion. To paraphrase Dr. Barbenheimer: It is become the World's Largest Tweeter -- Destroyer of Bass. :eek:



Even putting it in a Karlson couldn't help! ;)
Yikes- I may have one of these hanging on the wall out back. '1967'ish, good for- 30-35 watts or so? :rolleyes:
 

sigbergaudio

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mhardy6647

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Which driver is that?
A 15 inch Sica-made DVC subwoofer -- it is (they are: two of them) enconsed in a prototype subwoofer that I acquired a few years back. One forward-facing, the other downward-facing.
I know nothing else about it (them), but the availability of four voice coils in toto affords numerous wiring configurations to play with.
It was meant to be used with a plate amp and DSP. I bought the cheap "250 watt" PE Class D plate amp (with some rudimentary DSP) when it came out to use with it.
No complaints, but I have done very little exploration of its capabilities. :(



Pay no heed to the (ahem) passive high level XO to the left, sitting on the EV Coronet enclosure :) -- it was hooked to something else entirely at the time the photo was taken and is irrelevant to the subwoofer.

The plate amp, FWIW:

Note my hand-crafted, artisanal enclosure for the amp :facepalm:
It's actually open-backed to help with airflow (but mostly due to some clearance obstacles.). ;)
 
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sigbergaudio

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A 15 inch Sica-made DVC subwoofer -- it is (they are: two of them) enconsed in a prototype subwoofer that I acquired a few years back. One forward-facing, the other downward-facing.
I know nothing else about it (them), but the availability of four voice coils in toto affords numerous wiring configurations to play with.
It was meant to be used with a plate amp and DSP. I bought the cheap "250 watt" PE Class D plate amp (with some rudimentary DSP) when it came out to use with it.
No complaints, but I have done very little exploration of its capabilities. :(



Pay no heed to the (ahem) passive high level XO to the left, sitting on the EV Coronet enclosure :) -- it was hooked to something else entirely at the time the photo was taken and is irrelevant to the subwoofer.

The plate amp, FWIW:

Note my hand-crafted, artisanal enclosure for the amp :facepalm:
It's actually open-backed to help with airflow (but mostly due to some clearance obstacles.). ;)

Cool. Appears to be a discontinued driver.
 

fpitas

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Pay no heed to the (ahem) passive high level XO to the left, sitting on the EV Coronet enclosure
My eye went straight to the HV capacitor.
 
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