treating cones with rubber cement

[MisterTwister]

this is frequency response of driver from klipsh 4.1 pro media subwoofer. I found rubber cement coating to be most effective resonance damper for paper cones. before treatment frequency response above 1k was a total mess.
both cone and surround are treated.
and copper ring added of course 🙂

 

[MisterTwister]

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[rl guy]

can you elaborate on how to add the copper ring? or is there a link that describe the process? thanks

 

[MisterTwister]

you just need to find copper ring of appropriate diameter. I buy them at home depot plumbing supply section.
if your driver has vented pole, you can just use long screw and pieces
of wood from both sides.
if pole is not vented, I'd use epoxy or thermal glue to glue long screw on top of pole piece. then use piece of wood (could be bullet shaped) to hold it all together.
there are may be better ways of attaching rings.
in this particular driver ring just sits on top, it's not affixed yet.

 

[infinia]

Is the copper ring you added supposed to function as a shorted circuit (shorted turn) for the motor assy. If it is, shouldn't it be shimmed between the coil former and pole peice, at least within xmax? Although this will be extremly difficult to do (s/b tight clearances for a small fullranger) for a DIY.

<edit> Can you post graphs of before the mods?

 

[MisterTwister]

unfortunately I don't have original measurements saved.
I can only show measurements with and without ring if you are interested.

 

[rl guy]

yes that would be interesting to see. not that i have any doubt that the ring doesnt work for you.

 

[MisterTwister]

here is the graph.
I have shown my ring mods in three threads already. the main point here is try to use rubber cement on paper cones 🙂
only problem is that cone remains sticky.