My First DIY Project - Sub

[Shadow2121]

First of all thanks to all of you who have documented their builds and research. It's been inspiring as to getting my hands dirty.

As I am currently without a sub for my HT system, I've decided to start there.

My enclosure is a stand made out of higher quality plywood, and before driver/bracing is approx 4.8 ft^3. It will be connected to a Yamaha rx-v667. So far this is my intended BOM:

Dayton Audio BPT-38G Binding Post Pair w/Tab Part Number: 091-340
$8.26

Speaker Cabinet 1/2" Super Toe Spike Set 4 Pcs. Part Number: 240-730
$6.90
Cast Frame 1/4"-20 Speaker Mounting Kit Part Number: 260-778

Dayton Audio SW-25 Subwoofer Cable 25 ft.
Part Number: 181-644
$22.44

Speaker Gasketing Tape 1/8" x 1/2" x 50 ft. Roll Part Number: 260-542
$6.88

Bash 500W Digital Subwoofer Amplifier Part Number: 300-752
$238.58

Dayton Audio RSS390HF-4 15" Reference HF Subwoofer 4 Ohm Part Number: 295-468
$159.90
Subtotal: $446.55

I have insulation left over from insulating my garage to use for fill. As far as I've read this should be sufficient.
I haven't decided whether or not to box the amp internally or externally onto the back of the sub.
Please offer your input on any cost saving measures I may be overlooking. Or more likely, anything I have overlooked into including. Or of coarse the third option of easy upgrades.

Also I believe I am going to downfire this, what is the recommended ground clearance?

[BOBinGA]

It's out of stock until June, but this is much better boom for the buck than the Dayton Bash amp:

http://www.oaudio.com/500W_SUBAMP.html

Lots more bass management features and the same basic amp.

-Bob

[Shadow2121]

Thanks for that, I like it and will probably wait for it to come in.

[Eric S]

I presume you are planning on a sealed sub (given the size you quote). Regular fiberglass insulation should be fine for sealed, but if you are working with a vented sub, I'd go with polyfill or other cotton/polyester batting.

[DeathMonk]

I think you have that backwards

[Eric S]

Ooops- yes, I mixed up the driver sizes for vented/sealed...

Either way: Use cotton/poly for vented, save the fiberglass for sealed enclosures.

[Shadow2121]

Yes I plan on a sealed enclosure. But thanks for the heads up, I was unaware it made a difference.