New Aux Woofer

[Mike B]

I am so happy with the sound of the Tangband W8-1772's that I am going to build a sub on the same design format.  Neo motor, low mass and low inductance.  I figure this should result in "fast" performance.

Going with Peerless Vifa NE225W-08.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=264-1138

Going in a 30 liter net box tuned to 40 Hz with a 3" dia. port ~9 inches long.

F3 is 40 Hz according to win isd

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3671%2F10107455955_30d9b53fe0_o.jpg&hash=7602c6ca7ab4a89d1a3bd5eabf0b49e37c917575)

Now I have 2 wonderful $200 full range mains and a $40 sub.  Going to see what a nicer driver sounds like, one on the same design -

[Mike B]

Driver isn't here yet, but I got wood.  They all look the same in the beginning.  4 sides, 2 baffles, 1 brace, 1 face board, 4 cleats and a port.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm3.staticflickr.com%2F2886%2F10261832583_e917c2dc35_o.jpg&hash=145f59a5fcfe4e74b5bb4a157f882c80c700fe53)

All cut up nicely on my $100 table saw.  I have built a couple dozen speaks with this cheapie saw and if I can do it so can you.

This is oak veneer plywood from Lowes, nice stuff.  Cleats installed and 4 sides gluing up.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm6.staticflickr.com%2F5343%2F10261621154_a2d97c4330_o.jpg&hash=86b730cdc8b6cde0eb819c8bedc584d81d806dcc)

I love the smell of sawdust in the fall -

[Mike B]

There was a box outside today when I got home -

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3667%2F10283880216_d295e42fc2_o.jpg&hash=3d833d2ef63bc5f8845c7bdd49fa0e38c84b8e81)

But the back is the best.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm3.staticflickr.com%2F2823%2F10284004543_a584847b86_o.jpg&hash=2291de6cff7339ea8d20f11916d0204134f4f0cf)

Solid cast frame, spider mid mounted floating in space with tinsel woven in, neo motor caged on top.  The copper you see is the voice coil.  It really is too pretty to put in a box.  But that's where it belongs 'cause the gap is right there too.

There is zero flux leakage on the motor, couldn't even stick a paper clip to it.  Amazing.

Gaskets front and back.  Nice piece of work, you really do get what you pay for -

[Grainger49]

That is a Muttah of a woofer.

[Mike B]

The weekends work.

I designed the brace to support the port and needed to check the alignment before gluing.  The other one I did like this was centered, this one is offset.  It really is a custom job meant to fit in my stand and leave as much space as possible for records.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3687%2F10395143594_c9b5e51582_o.jpg&hash=b737be4393a3dc9ba74b9b698a247c6cdea33e31)

Yeah baby, perfect.  I'm going to fill the gap with silicone bathtub caulk.  The port tube is glued rigid to the baffle with ABS cement and I want the thing to not stress with humidity.  The brace is going to be glued to the front side of the cleats, this is just for test.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm8.staticflickr.com%2F7386%2F10395321453_1141ae3558_o.jpg&hash=cd17006d3b98a27ef90aa01503dab4cbf7c826c3)

All glued up.

[2wo]

Cool brace work. Looking at the last photo, with that chimney, you could smoke some ribs ...John 

[Paul Birkeland]

Yeah baby, perfect.  I'm going to fill the gap with silicone bathtub caulk.  The port tube is glued rigid to the baffle with ABS cement and I want the thing to not stress with humidity.  The brace is going to be glued to the front side of the cleats, this is just for test.

I'd avoid ABS cement for gluing ABS to anything but ABS, as it's a solvent welding type cement, so it won't help you get your ABS to stick to wood.

For that job, contact cement and epoxy are well suited. 

This looks like a cool sub project, let us know how it goes!

[Mike B]

Too late, it's glued.

I am not worried about this, I have done it before.  I have verified that ABS cement sticks to wood tenaciously.  If you get under it and pry it takes the wood with it.  The hole in the baffle is routed ~1/2 deep.  I smear some cement on the end of the tube and the sides and insert the tube in the countersunk hole.  Then I use an eyedropper and fill the gap between the wood and the pipe with cement.  You are correct, the cement will not dissolve wood, but it does inpregante the pores and hardens to solid plastic one the solvent evaporartes.  Takes a long time, at least a day cause there is a deep pocket of glue.  It does solvent weld the pipe.

The result is that pipe is never coming out of there.  If you levered it the baffle would break first.

I used to use polyurethane glue for this task, believe me pipe cement is better -

[Paul Birkeland]

Yeah, I have used polyurethane glue to adhere ABS pipe to plywood, and it doesn't work that well.  The ABS can still pop out unless you notch the pipe and give the glue something to hold onto.

Epoxy doesn't seem to have these issues.

I hadn't considered that ABS cement would get into the wood and harden, I'll have to give that one a try!

[Mike B]

Front baffle gluing up.  Using half inch PE "sonic barrier" foam.  I like this stuff, apply contact cement and stick it on.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm6.staticflickr.com%2F5475%2F10486617005_695ac87be3_o.jpg&hash=16d434fac2cf36bb34554d125b4b16a66849d5b8)

Tomorrow I caulk in the port tube and install the face board and if all goes well I should have the rear baffle gluing up  by the end of the weekend.

[Mike B]

Got the front baffle trimmed up nice.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3718%2F10529683044_c87772ea25_o.jpg&hash=a6123d801326cb2fe91e74463b0bb896e23f1a3d)

Glued in the port brace with silicone. Made up a face board.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3717%2F10529649826_901ea4958d_o.jpg&hash=d6d61d30e9a9890ba92703eb90c9aef676aa7061)

Every time I build something I screw it up. You try to be careful, you double check and sometimes you get this;

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3767%2F10529872173_83c478009d_o.jpg&hash=3c7138826af5990b5c4d9dc5978d0006846fe5df)

No overhang, no good. Made up another face board and was a little more careful. Glued in, trimmed and looking good.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm8.staticflickr.com%2F7382%2F10529872633_df83dcd924_o.jpg&hash=76772093e6dc3c39ac0b95ca9414637e9451988f)

Sounds good too. A cone thump yields a nice 40 Hz tone out of the port even all leaky sitting on the bench.

Now on to the rest.

[Grainger49]

Looks very solid.  I'm looking forward to hearing how it sounds to you.

[Mike B]

It looks so good you are speechless?

[RPMac]

I thought Grainger had a profound statement...if I could have read it! (yellow doesn't work)

Mike, check out my bracing comment on the other thread. I meant to post that here, but probably too late to try on your sub.

[Grainger49]

Every so often when I change the font and color I pick "Beige" in stead of "Blue."  You can see it faintly but for all intents it is invisible. 

I'll try to do better with this post!