A question about trim rings around speaker drivers

I would say that we see more problems from over tightening bolts than under tightening them.  Most baffles made of a non resonant material are soft and can be compressed between a bolt and a driver frame, so it's normal for a bolt to "feel" loose.  It may not necessarily be so.  I have seen some speakers that are 10 years + old have a loose bolt or two- but I cannot recall anyone sending a speaker back to us for repair solely over these loose bolts.  I would say if they are tight by your hand, using only your fingers, that's enough. If you put a big long wrench on them and tighten them until you cannot tighten anymore, you've gone way too far.  I would expect tightening bolts with a big wrench twice a year will likely destroy the baffle in time; I have actually seen this in our ATC service department where we had to replace a baffle from over overtightened bolts.

One might jump to the idea then why not make the baffle metal or some other non compressible material?   Super hard baffles have other negatives (such as resonances) to deal with that can be far worse to sonics than a loose bolt.  

Lock tite makes it challenging to get the bolts off when to comes to replacing a driver.  Ive seen my service techs struggle over this too, even to the point of sawing the bolts off to replace a damaged or blown driver.

Brad     

I'm much more worried about speakers, especially small speakers on tall stands, rocking back and forth than I am about a wood screw ever coming loose.

If you have a small, stand mount it's sometimes beneficial to add weight to the top.

I would guess it depends on the screw thread, the material, and how much they were tightened in the first place.  

With older speakers it's prudent to rotate the woofers 180 degrees every few years to offset the pull of gravity on the suspension, but never once have I encountered loose woofer screws.  

@roxy54 ,

Rox, just started a thread reminding people for the New Year to check to see if they have a screw loose!

Just checked the screws on my Avance speakers, surprisingly unsnug. Had to rummage around to find a T10 torx head bit to do it. Tightened up the drivers, tightened up the sound!

@thecarpathian 

Thank You Sir!

This isn't a ''maybe" or "sometimes", it is something that I believe must happen with all speakers. I have had this experience with almost all of the 20 sets that I have owned over the years. I think I picked up the habit from advice that I read in one of the Brit mags many years ago.

@knotscott

I had to chuckle a bit when you said that you had never encountered loose woofer screws, because they are the drivers that become loose most frequently due ti the heavy movement and vibration!

This isn't a silly tweak, it's part or regular system maintenance. Of course, you need to use common sense and don't over tighten.