[jk@home]

I need some help choosing materials to isolate an external crossover box that will be resting on the pedestal of a modded Magnepan MMG, similar to the Magnestand products.

The components will be strapped on ¼” x 8” x 8” pegboard with plastic wire ties, maybe some teflon tape as insulation between. This assembly will weigh about 5 pounds.

This will float in an oversized MDF box, with damping material on the inside bottom, sides, and top. The additional weight of the box is around 8 pounds or more, depending on what damping material I use (am open to suggestions here ).

I’m mainly looking for a recommendation for what Herbie product would be best to place under the box, on top of the butcher block platform. Something low profile preferred.

Here's a pic of the speaker, crossover wired in temporarily, minus oversize box (the frame will ultimately be covered with a MG12 sock):

[Herbie]

Four or five regular 1" diameter grungebuster Dots between the box and platform should do very well. If vibrations are fairly severe, Extra-Thick grungebuster Dots work very well with crossover boxes also.

For the box itself, press a good bead of rope caulk along the seams and then fill the box halfway or so with playground sand. If the box is going to be enclosed, skip the playground sand and just use plenty of rope caulk (available at hardware stores) on the bottom, sides, under the top.

Steve
Herbie's Audio Lab

[jk@home]

Excellent, I'll get an order to you next week ASAP.

Sand was one of my options; I have a bag of Q-ROK quartz construction sand that I can use. I wanted the extra weight of the sand on the platform, was hoping you would recommend something that can handle the extra weight. If that's the case, maybe I should go for the Extra -Thick units.

I already have some of that rope caulk also, should be good to go!


http://db.audioasylum.com/cgi/m.mpl?forum=mug&n=156708&highlight=replisand+substitute

Question: why would I not want to cover the box, if I used sand? Should I leave room for slight ventilation?

Thanks
John K.

[Herbie]

Grungebuster Dots will handle a lot of weight. Wider Dots will handle more weight though, as will thicker Dots. Weight is usually less of a factor than the amount of vibration the Dots are dealing with. You wouldn't go wrong with Extra-Thick grungebuster Dots.

Nothing wrong with covering the box. I'd recommend it to function as a dust cover and for neat appearance. By an enclosed box, I meant one with a sealed top. Someone might inadvertently tilt the box sideways or something and get sand all over the electronics--other than that, nothing wrong with it.

Steve

[jk@home]

Thanks again Steve