Cast alloy sub "cabinet"

[OzMikeH]

I stumbled over some cylindrical cast alloy things. they are tapered cylinders about 3/4 inch thick with reinforcing ribs down the sides. seriously strong!

I had the old woofers lying around so I crunched the numbers and Qts = 0.71 and a Cylinder, Perfect!

hopefully the 10 year old automotive JBL drivers will handle being driven by an equalised amp.

My Tannoy main speakers allegedly roll -3dB at 45Hz according to the brochure (I should have tested this but didn't)
I want to use an EAS EQ on the subs bringing them in at 45Hz to fit with the mains.
I manually swept one of these subs in the room with a sig gen and sound level meter. There are 2 equal peaks at 50 and 60Hz with a 5dB dip between.
From 50Hz it goes down pretty evenly to -17db at 30Hz

they will be run in a pair, next to the main speakers or used as stands for the mains - downward firing.

they are half filled with very loosely packed polyester wadding.

Did I do the right thing with the stuffing?
Has anyone else used Aluminium sub housings, will they ring like bells?
How believeable are Tannoy spec sheets?

Will post a pic when I find one.

[BassAwdyO]

I have a beer keg sub out in my garage... I believe that it's made from stainless, not aluminium. Yes ringing would be a problem if it was run full-range, however if only used for a sub, the metal resonates way too high for it to be excited by the signal it gets.

I stuffed the beer keg sub with a bit of fiberglass insulation, but I dont really believe it NEEDS it. One thing that is hard to deal with these things is the fixed box volume... For my little project I just used a 8" driver which would have loved 1cubic ft enclosure. the 3cube volume of the keg lended itself nicely to a EBS however

Sounds like a good project... Pics would be nice

[OzMikeH]

Bricks glued down with sikaflex are good for fine tuning the volume.

These were the perfect volume for these drivers. the cylinder is slightly tapered, 10 inches at the bottom and 9 at the top.
you can see how thick the casting is.

[OzMikeH]

top. one has the window (1/2 inch laminated, tempered glass)
the other has a piece of MDF.

[MJL21193]

Wow. Not going to win any beauty contests, is it?

[OzMikeH]

with driver. yeah, I know i didnt need that many bolts but the holes were there.
the grille has since been removed and it stands driver down on three 3" by 1/2" UNC bolts tapped into the MDF end plate with felt feet.

now how the heck do I pretty these up for the wife??
any ideas?

[MJL21193]

Originally posted by OzMikeH
with driver. yeah, I know i didnt need that many bolts but the holes were there.
the grille has since been removed and it stands driver down on three 3" by 1/2" UNC bolts tapped into the MDF end plate with felt feet.

now how the heck do I pretty these up for the wife??
any ideas?

If she doesn't like that, there's something wrong with her.

[OzMikeH]

It does look pretty hardcore doesn't it?
I need to make them look more like furniture and less like bomb proof nuclear waste containers.
maybe octagonal covers make from 1/2" veneered MDF. Easiest would be a vinyl sock with some foam under it but that is a bit too weird.

[auplater]

I'd sand blast the heck out of it to get that matt chrome-like finish that looks so sexy....

The you could spray paint some highlights where the various old fixtures were attached