This is really odd, but I recently got a Markbass LMT 800 head. I am rewiring my ancient Peavey Combo 300 combo amp. I've removed the head for testing, and I have rewired the 15" speaker to plug into my Markbass. When we got it back together, there is a terrible distortion . Through tons of random experimentation, we have turned the cab upside down, and the distortion goes away. We have checked the polarity of the wire, and tried it both ways. We have tightened/loosened the screws in the speaker, we have cleaned the groove for the driver, and we have visually inspected the voice coil. Any ideas?
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BASS CAB ONLY WORKS UPSIDE DOWN
- Thread starter coltranius
- Start date
I have heard that some speakers can sag while sitting for years, and then firing them up may cause the speaker assembly to rub...although this did not happen to a Fender 2x15 cab that I had in storage for 20+ years. I'm wondering what would happen if you simply removed the speaker and re-installed it after rotating it 180 degrees. If there were a sag or set in the cone, that would have the same effect as turning the cab upside down. How long that would work, I have no clue.
My first thought was a loose wire or component other than the speaker, but it appears that you have explored that possibility.
My first thought was a loose wire or component other than the speaker, but it appears that you have explored that possibility.
Had a Combo 300 Sounded Real Bad Lots of distortion . Removed the speaker and head re-glued the cab together where all the panels come together . Also made some L brackets and bolted att the panels top and bottom Problem solved no more distortion . Distortion was nothing more than the old cab that had come unglued vibrating.
billfitzmaurice
Commercial User
- Sep 15, 2004
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I had a similiar problem with an eden of mine. When I played it "regular" it would distort and buzz, when I turned it on its side, it went away. I had a wire laying on the speaker cone. When I turned it sideways the wire didn't touch the cone, and the buzz went away.
That would be "no, you haven't" to be a grammatically sound refutation.No you didn't.
But in this case they probably have. Many Peavey speakers come with a bolted-on magnet, which exposes the voice coil in all its glory when removed.
- Dec 18, 2000
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Another possibility with really old Peavey basket/motor assemblies:
Gap has crap in it. Often this will be broken-down foam that was originally glued against the screened cooling vent on the back of the magnet. So, roll/fold some masking tape at least a couple layers deep with the adhesive side out, then stick it down into the gap until you hit the backplate and with the bit that's still standing out, and "sweep" the entire gap circumference at least once. Any crap in there should stick to the tape. Then pull it all out.
Gap has crap in it. Often this will be broken-down foam that was originally glued against the screened cooling vent on the back of the magnet. So, roll/fold some masking tape at least a couple layers deep with the adhesive side out, then stick it down into the gap until you hit the backplate and with the bit that's still standing out, and "sweep" the entire gap circumference at least once. Any crap in there should stick to the tape. Then pull it all out.
You have all got it wrong. This speaker is meant to be used in Australia. That way it will be right side up!
- May 9, 2008
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By Jove! I think you are onto something here, that, or was it an Argentine export model.You have all got it wrong. This speaker is meant to be used in Australia. That way it will be right side up!
Indeed, that is the case. I also cleaned the gap with tape as suggested. I'm pretty sure there is no debris, and no wires touching.
I did try removing the speaker and rotating it 180, but that seemed to make it worse.
Some history here:
One week before halloween, the cab was driven too hard at an outdoor gig with inadequate PA. On halloween, it was used for onstage bass sound with a good PA, at fairly low volume. Twice, the cab shutdown with no warning, and restarted with no warning. That prompted me to go ahead and get a good head, and now I need to have a working cabinet. I'm trying to decide if I should buy a new Black Widow to replace the old one, or if I should buy an Eminence 15" to replace it, or if I should just build a new cab. Right now I'm leaning toward the new cab.
And Mr. Scott:
+1 Australia
wait...if it works upside down...you should totally rock that thing upside down. i'd think you're cool...no one else might...
Post the model number on the speaker, BFM and others can tell you if it would be worth getting a replacement basket (cheaper than a whole speaker).
I'm away from the cab right now, so I don't know the exact model #. Its a 400W RMS 4 ohm Black Widow 15". Don't know the exact age, but I'd guess at least 20 years.
And to INTERNETKING: Thanks, man! I have a friend with the exact sentiments.
