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Did Fleetwood Mac's "The Chain" blow up my woofer?

System: Ortofon 2M Red > Musical Surrounding Phonomena II > PS Audio Stellar preamp > M700 monoblocks > Buchardt S400 

Phonomena is set to 46db of gain, 200pF capacitive, 50k Ohms resistive

The other day I was playing "The Chain" off of Rumors, and one of the woofers stopped entirely during the bass guitar interlude. It just went completely silent, no pops, crackles or distortion. The tweeter is fine, and I reversed the L and R channels to confirm this problem is in the right woofer. The volume level was a "strong" listening level (30 out of 100 on the Stellar), but not loud. We were still able to converse just fine without raising our voices much at all. I have certainly listened to these speakers much louder with other sources.

I understand the power amps are overkill, but I figured my ears would bleed far before I was in danger of blowing anything up. Was this distortion? Subsonics? Woofer pumping due to poor TT isolation? Or a simple defect in the driver?


jayy42
mulveling's avatar
mulveling
1,774 posts
 
If you have woofer pumping it should be visible, because the woofers will be moving a great distance at sub-sonic frequencies. Sometimes lighting can highlight the issue. When I upgraded my rack & turntable to the current ones, absolutely all traces of woofer pumping completely vanished - not that it was too bad before. It can be either your turntable, or lack of isolation, setup, or any combination. If everything is right, a rumble filter will not be necessary.

And my tech also checks the woofer's freedom of motion - if that's all good your woofer's mechanics are usually OK. 
erik_squires
15,877 posts
 
PS - Another quick test is to use a 1.5 or 9 V battery on the woofer.

It either moves, or it doesn't.

Perfectly safe for all drivers.


homer_skins's avatar
homer_skins
30 posts
 
I highly recommend the KAB RF-1. It is unique and does more than your average rumble filter. Check it out on his website. I have had one in my analog chain since about 2011.  Can't live without it since I have two subs which I run with my vinyl. It rocks! Dana
twoch
429 posts
 
no  ,   your amp did  dirty
in dirty out  
bac2vinyl
78 posts
 
One stupid post!
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