Buzzing/vibrations from one of my BM6A's at certain freq's

aqua_tek · Post by **aqua_tek** » Sat Dec 06, 2008 9:36 pm

So, when playing back beyond a certain level, and when certain low frequencies come in (havent checked which ones exactly), I could hear some buzzing on my left BM6A. Sounded like something was kind of loose and vibrating real fast. After some investigation, I noticed that if I pushed the back panel in, at a specific corner, the buzzing stopped. So its obviously that buzzing indeed comes from something loose.

I wrote to Dynaudio about this, and someone over there replied, suggesting I just tighten up the screws in the back. I did it, and it kind of stopped buzzing for a while, but it came back. Not sure what to do next. Sounds like something that should be simple to fix, but I'm scared to tinker too much with it myself. Ideas? Don't want to spend a ridiculous repair fee for someone to just tighten a couple screws inside.

abort · Post by **abort** » Sat Dec 06, 2008 9:58 pm

I would recommend loosening up the screws around the sounding area enough to access the rim around that back plate and shoot a small amount of silicone sealant behind it ...screw the plate back on. (no need to wait to dry)

By the way "Come ON" fucking rocks.

wildstyle7272 · Post by **wildstyle7272** » Sun Dec 07, 2008 1:23 am

abort wrote:I would recommend loosening up the screws around the sounding area enough to access the rim around that back plate and shoot a small amount of silicone sealant behind it ...screw the plate back on. (no need to wait to dry)

By the way "Come ON" fucking rocks.

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aqua_tek · Post by **aqua_tek** » Sun Dec 07, 2008 3:11 am

abort wrote:I would recommend loosening up the screws around the sounding area enough to access the rim around that back plate and shoot a small amount of silicone sealant behind it ...screw the plate back on. (no need to wait to dry)

By the way "Come ON" fucking rocks.

Thanks for the tip. I'll try that.

And thanks for the props! Sadly, had to make a choice and decided to remove that one from my profile to make space for a new track. Yay myspace and their 6 track limit.

It's still here
http://soundcloud.com/nathan-vice
http://fairtilizer.com/users/NathanVice

chasedestroy · Post by **chasedestroy** » Sun Dec 07, 2008 7:12 pm

i had a similar issue recently with my event 20/20's. turns out the dustcap for the voicecoil had come loose. upon detecting the issue i removed the dustcap, everything back to normal

of course now one of my speakers looks super ghetto fabulous...

i talked to a technician about what type of adhesive would be best to re-attach it, and what would be best to use to remove the remaining adhesive from the speaker cone... he said he had no idea, normally they just replace the woofer.

thanks a TON Mike @ Event.

abort · Post by **abort** » Mon Dec 08, 2008 5:21 am

chasedestroy wrote:i had a similar issue recently with my event 20/20's. turns out the dustcap for the voicecoil had come loose. upon detecting the issue i removed the dustcap, everything back to normal

of course now one of my speakers looks super ghetto fabulous...

i talked to a technician about what type of adhesive would be best to re-attach it, and what would be best to use to remove the remaining adhesive from the speaker cone... he said he had no idea, normally they just replace the woofer.

thanks a TON Mike @ Event.

Hey Mike! You should probably use something more permanent for your issue. For a DUST CAP maybe something like super glue or ..epoxy.

I was only thinking 'silicone sealant' would be good for stopping vibrations not adhering a dust cap. I mean this might work but

dancerchris · Post by **dancerchris** » Mon Dec 08, 2008 9:05 pm

It depends on the dustcap. Is the dustcap "breathable"? If so then white glue would work fine. If not then a rubber based glue or sealant would be good as the more brittle glues like superglue are likely to fracture in a flexible vibrating environment like the speaker cone. I have rebuilt several speakers and these have worked for me.

Another problem may be that the voice coil is scraping. Your sealing problem on the back could just exacerbate the cone/coil problems by changing the Thiel/Small parameters of the box. If it is a wooden enclosure you may have a stripped hole and the screw is not holding. Try a larger screw or put some white glue and fine sawdust on your screw. You'll be able to back out your screw but it will help give a better anchor if your threads are stripped (easy to happen in MDF enclosures).