PE cabinet baffle rattle

[bmaupin]

I recently made a couple pairs of speakers with PE cabinets - one with the 0.75cuft MT & the other with the 0.75cuft MTM. On some songs at a fairly high volume I get cabinet/baffle rattle. When I first only had the MT pair I thought that maybe it was the woofer (SS18W4545), but after completing one of the MTMs and testing it out I was able to reproduce the same buzz/rattle sound. It is easy to feel that the cabinet does not vibrate much and that the baffle does. The rattle is not created by the deepest bass notes and seems to be a particular resonant frequency.

I was wondering if others have experienced something similar with PE cabinets or any other cabinet with a bolt on baffle and what have you done about it, if anything. I remember Philip A telling me that he uses foam on the baffle rear flange. I was thinking that after I have had plenty of time to finalize each design that I could install some additional bracing to connect the baffles to the center brace and permanently glue the baffles on, but I sure do like the idea of being able to use the cabinets for other driver combinations by making new baffles - at least for testing purposes.

- Brad

[johnastockman]

http://custom.smugmug.com/photos/249175185-L.jpg


> I recently made a couple pairs of speakers
> with PE cabinets - one with the 0.75cuft MT
> & the other with the 0.75cuft MTM. On
> some songs at a fairly high volume I get
> cabinet/baffle rattle. When I first only had
> the MT pair I thought that maybe it was the
> woofer (SS18W4545), but after completing one
> of the MTMs and testing it out I was able to
> reproduce the same buzz/rattle sound. It is
> easy to feel that the cabinet does not
> vibrate much and that the baffle does. The
> rattle is not created by the deepest bass
> notes and seems to be a particular resonant
> frequency.

> I was wondering if others have experienced
> something similar with PE cabinets or any
> other cabinet with a bolt on baffle and what
> have you done about it, if anything. I
> remember Philip A telling me that he uses
> foam on the baffle rear flange. I was
> thinking that after I have had plenty of
> time to finalize each design that I could
> install some additional bracing to connect
> the baffles to the center brace and
> permanently glue the baffles on, but I sure
> do like the idea of being able to use the
> cabinets for other driver combinations by
> making new baffles - at least for testing
> purposes.

> - Brad

Brad, I use the PE foam gasket tape, but you can use any medium to firm density weatherstripping. I've never had a baffle buzz/rattle using it before actually glueing the baffle in permanently. I do the same thing...wait until I'm satisfied with the sound/XO and then glue the baffle. Here's a pic of some .5 ft3 PE boxes where I did add a brace between the center brace and the front baffle. Probably over-kill, but you can do it. I've also gotten a pair where one of the inserts for the baffle screw was loose and spun while trying to attach the baffle, so that might be something to check. Try some foam gasket tape...it has worked well for me.

John A.

[philiparcario]

> Brad, I use the PE foam gasket tape, but you
> can use any medium to firm density
> weatherstripping. I've never had a baffle
> buzz/rattle using it before actually glueing
> the baffle in permanently. I do the same
> thing...wait until I'm satisfied with the
> sound/XO and then glue the baffle. Here's a
> pic of some .5 ft3 PE boxes where I did add
> a brace between the center brace and the
> front baffle. Probably over-kill, but you
> can do it. I've also gotten a pair where one
> of the inserts for the baffle screw was
> loose and spun while trying to attach the
> baffle, so that might be something to check.
> Try some foam gasket tape...it has worked
> well for me.

> John A.
if you want to remove the baffle go to walmart in the arts and craft section and buy black peel and stick felt sheets 8 by 10 inches for about 1 dollar cut them as wide as the edge of the cabinet that the baffle lays on. about 3/4 of an inch. the whole edge will have black felt. use a sheetrock knife and a ruler to cut. this will stop the rattle. you can glue this later without removing it. just use carpenters glue right on the felt. than bolt the baffle on and wip the glue. don't do it now just use the felt . the weatherstrip will work but the felt is better. phil a.

[dennymo]

Darn, I mis-read this as "PE cabinet baffle *raffle*"