help on dampening please

[welly_59]

hi guys, i've just finished building the speakers attached below, but was wondering where i should place dampening material inside. I've bought the damping material already but am not sure if it needs to be placed in both enclosures or not. Also where in the cabinet should i mount the crossover? thanks a lot for your help

 

[rabbitz]

For a vented enclosure I tend to put damping on the back, top and sometimes one side only but for this I'd put it on the bottom instead of the top. For the sealed upper box, fill it up. Wack the crossover on the back wall near the speaker terminal and seal the wiring going into the upper box.

That's a very wide baffle. How thick's the MDF - can't read the sketch real well.

 

[welly_59]

the mdf is 18mm thick. What do you mean by saying the baffle is too wide?

 

[rabbitz]

I'm not saying it's too wide as you need this width to fit that huge woofer.

The question on the MDF thickness was to see what was used. I'd add some bracing or stiffeners as you want a solid support for the woofer.

 

[welly_59]

theres a brace going along the back at about 300mm, shoul i add more?

 

[rabbitz]

Put some in from the front right to the back panel and also glued to the sides, bottom and top. Will help the sides as well. Also glue some blocks where your speaker screws go into the baffle so the screws go through the baffle and also into the blocks.

See the marked up sketch.