A question about trim rings around speaker drivers

@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!

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.  

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 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     

@stereo5 

Do you know if locktite was used ? I've never seen it on any speakers I've had. If not, I'll guarantee that your drivers are loose.

My GE speakers grills are very time consuming to take off, the speakers still sound the same as they did 7+ years ago and I will not fool with them.  If Locktite were originally used on the screws, I see no need to tighten them. 

It's worth doing, but be careful not to over tighten.  You can also check the loudspeaker's binding posts.  They to can come loose.  It cost you nothing to inspect.

If you haven't you should. A driver is ideally supposed to act as a perfect piston, and if it is loose and shaking that isn't possible, and yes, it is very audible. I'm sure that there are members here who will say that they check them on aa regular basis.

Two years ago, I picked up a 2-year-old set of floor standing speakers from a man in California. He had a nice system and two other pairs of good speakers. When I got them home and checked the driver screws, each of them turned for at least two revolutions!  I Immediately emailed him and told him to check his other speakers. He did and wrote back to thank me. 

This question has came up before and after reading through all the responses, I tried it on some speakers I had at the time that had visible screws. Every screw required some tightening with a couple that needed more than a quarter turn to do accomplish it. 

It surprised me.

All the best,
Nonoise

@kr4 

+1

Bob

Except for the speakers that I built or repaired, I have never bothered to tighten the screws on the drivers in any of the speakers I've owned over many decades.