Tightening Screws on Drivers

[EAmin]

I spoke to my dealer today who suggested that I use an allen wrench and tighten the screws on my 703 drivers. He said that I'd need to do this periodically. Apparently, it keeps the bass tight and accurate. They were kinda loose. Anyways, I thought I would pass along to you all. Thanks!

[BlazeMaster]

sounds cool EAmin, I'll go and do that right now.

[JürgenW]

As long as you don't mean the screw at the back of the speaker, it should be oké.

From the B&W site:

There is a large aluminium slotted screw at the back of my speaker, behind the FST midrange. What is it for and should I adjust it?

Apart from in the CM6, our FST midrange unit has an unusual mounting arrangement. The driver is mechanically isolated from its enclosure, whether it is the sphere / tube "head" or a more conventional cabinet, by flexible gel components in the fixing arrangement. To optimise the isolation, a single securing rod is used that runs from the back of the driver to the back of the enclosure. The tension on the rod is controlled by the large head straight slot screw at the back of the enclosure, and this in turn controls the pressure on the flexible gel parts. In order to prevent excessive movement of the driver under impact in transit, a clamping disc is fitted over the screw head, held in place by a cross head screw in the centre. On installation, this clamping disc and centre screw are removed in accordance with the pictorial instructions on the label fitted to the assembly.

It is important that the tension on the rod is set correctly. It is preset at the factory and should not require adjustment, except if the driver has to be removed for one reason or another, but sometimes it may get altered by mistake. This may be because one's natural instinct is to have a fiddle to see what happens, but occasionally removing the transit clamping disc has been known to loosen the main screw if it has bound itself in the thread.

If either of these has happened, refer to your local B&W dealer to have the tension reset correctly. We recommend that you do not attempt this yourself.

Jürgen

[EAmin]

I was referring to these screws, surrounding the driver.

http://www.bwspeakers.com/index.cfm/fuseaction/products.techfeatures/ObjectID/F61DE8CC%2DA4BF%2D4E2A%2D9FE4585810848498

[georgev]

Never thought of that, will check mine tonight.

[caleb]

Yes this is interesting.

The screws surrounding the driver on my 805s and 802's need to be retightened around once per year - they are not really "loose" but take a quarter turn just to keep them tight

[Pieter]

Been doing this yonks ago when I still had Matrix 805s.

Be careful and don't attempt to overtighten them, you'll strip the MDF "pseudo" thread.

[RobP]

Wow, I wish I would have seen this thread a few days ago, I have been having problems with my ASW850 sub bottoming out real easy under fast loud bass notes, after some time spent and right before my trip to the dealer I checked the mounting bolts and they were really loose, enough so that the cabinet was leaking air pressure.