mdf vs particle on a sonotube

[Jodean]

ok whats the deal.

1)I know mdf is really heavy and therefore probrably more dense for better bass.

2)Why is it ok to use a sonotube with 1/4" wall and then not ok to use particle board? Im lost.

3)Do you recommend i still use mdf for the sonotube ends, and is it really that much better than particle even though 80% of the enclosure is sonotube?

I finally ordered my tempest x and already have the 18" sonotube. I plan on making it around 5' 4" of sonotube. Ive read that around 6' this might interfere with sound waves????

4) should i go 5' 4" or somewhere else between 5 and 6'?

I plan on using the 6" pvc as a port as i found leftover on the jobsite. I believe i was reading about making that 32" long. I want the down low and not even sure what 18hz is since ive never had a driver that goes that low before....unless the infinity kappa perfect 12.1 in my car does it but not sure, its in a sealed box though.

5)stick with 32"?

[nova]

I've also wondered about that,... just kinda figured it had something do do with the strength of a cylinder vs a square box.

[SteveCallas]

MDF is more dense and smoother, and that will definitely come in handy when trying to slide the endcaps in place. It's also much easier to finish than particle board. I'd stick with MDF.

2)Why is it ok to use a sonotube with 1/4" wall and then not ok to use particle board? Im lost.

Sonotube is cylindrical, therefore the pressure inside the sub is evenly distributed along the entire surface of the tube, and it won't flex. For the endcaps, the deeper and heavier they are, the more rigid they will keep the sonotube and the less chance they stand of flexing, especially the baffle. A high excursion 15" driver can create a fair amount of force - you want a baffle that will remain inert.

The concerns some have with sonotube height do not really translate into problems in the real world listening environment. Many of us have subs even taller than yours with no isses.

As for the port, what enclosure volume and tuning are you targeting?

[Geoff St. Germain]

There's not necessarily anything wrong with particle board. I personally find it kind of nasty to work with and that MDF and good plywood machine better than particle board. Sonotube has intrinsic strength due to it's shape. It's why you can fill one of those tubes up with uncured concrete and it doesn't split.

[drf]

As far as human ears are concerned particle baord and mdf are sonically identical. The difference is that MDF will last a lot longer, is a little easier to work with and finishes better. If you are upto the challenge of getting particle baord to look good then by all means save a few bucks and use it. No-one else will know you have used it.

[thxgoon]

I'd add that any extra weight you can add to the end caps is a good thing. If you can double up on a layer on top and bottom this will help seal the sub as well when you glue it.

My subs are over 6' and have no probs. You going to post a build thread?

[Jodean]

thxgoon wrote:

You going to post a build thread?

http://www.hometheatershack.com/foru...html#post91270

[thxgoon]