DIY THT LP SubWoofer Build using 15" Dayton Reference

[cmsajith]

We like to call it a Coffin.

I got to listen to a diy THT at a Home theater by local area forum person. It moves lot of air, so be prepared to properly take care of anything that's hanging on the wall.

There will not be anything in that room which will be hangling or loosely fitted, I will be fixing them to the wall (paintings frames will be custom built and will be fixed at the backside and will not be visible outside) and the smaller items will be either glued or fixed using double sided tapes.

 

[captrajesh]

http://billfitzmaurice.com/THT.html: Looks quite similar (atleast externally) to the horn loaded sub woofer that one of our Calcutta based FMs was trying to sell.

All the best for the build.

 

[cmsajith]

http://billfitzmaurice.com/THT.html: Looks quite similar (atleast externally) to the horn loaded sub woofer that one of our Calcutta based FMs was trying to sell.

All the best for the build.

No, both are different externally. Eventhough both are horns, its the 36" x 36" x 24" or THT subwoofer. Mine is the Low Profile version of it (THT LP) which is mentioned in the same page.

 

[grubyhalo]

Awesome looking sub! What's the size of the room where this monster's going to live?

 

[anm]

I am working out in my head a subwoofer build. Unfortunately I can't put huge boxes in the living room. Will need inputs from you guys. Let me figure out placement and sizes possible.

 

[cmsajith]

I am working out in my head a subwoofer build. Unfortunately I can't put huge boxes in the living room. Will need inputs from you guys. Let me figure out placement and sizes possible.

You dont have to worry about the look of the box. You can easily make it to look like a normal furniture, similar to an av rack with shutters/drawers (false drawer handles can be used to shift the sub).

 

[grubyhalo]

I am working out in my head a subwoofer build. Unfortunately I can't put huge boxes in the living room. Will need inputs from you guys. Let me figure out placement and sizes possible.

How about a couple of Anarchys? You can safely place a couple of these in your living room without raising eyebrows. Ofcourse, these can go down 'only' till 25 Hz or so but is cheap to build and appears to have good, clean output by all accounts. Maybe if you open a new thread, you might get a lot of other suggestions? Here's a couple of small-ish inexpensive options:

Apex Jr 8" Super Sub Specs

http://www.apexjr.com/images/Super8PPBR.gif

They use the 8" driver and this plate amp from Apex Jr.

 

[anm]

will start a thread soon on sub. waiting to see where Danny's deal is headed.

 

[cmsajith]

Where can I find good Hex bolts and T-Nuts in Bangalore (preferrably near to whitefield / marthahalli / Bannerghatta road area) for fixing the driver. I am open to check the market / SP road also.

 

[captrajesh]

will start a thread soon on sub. waiting to see where Danny's deal is headed.

Hey Anant, don't break my heart:sad: It is headed in the right direction.

 

[santhosh]

Where can I find good Hex bolts and T-Nuts in Bangalore (preferrably near to whitefield / marthahalli / Bannerghatta road area) for fixing the driver. I am open to check the market / SP road also.

You get them in SP Road. I don't have the address of the shop with me. PM sunilj, he might have the address. We bought together.

 

[sunilj]

Sajith,

SP road is your best bet. Haven't seen them any other place but I can't be sure. You enter SP road from the town hall side, walk towards the end, where the hardware shops are situated.

Ask around for:

Saleh & Sons (on the main road, right hand side)
Babji (smallish shop around a tight corner, left hand side - crazy sh1t load of nuts and bolts)
J.C.Gupta (on the main road, left hand side)

One of them will have it. I scored from Saleh. Very very reasonably priced. I think a set of 8, nut and bolt is about Rs.200. Be careful of the size, confirming the dia of your Daytons, before buying. Comes in M5/6/7/8. The M4's are on order only - 1000 pieces or more. Good luck.

Regards,
Sunil

 

[cmsajith]

Thanks Santhish n Sunil, will check it out.

 

[sunilj]

Hi Sajith,

A couple of points came to mind about the THTLP. Along the line profile I've seen people damp the corners. What that means is, fix some damping material where the line turns into another section, 12-16" should be fine.

And...the big one, I noticed you mentioned the mouth is firing upwards towards the ceiling, effectively making it 2pi I think. Since the THTLP has an extreme mouth exit, work something to hold, just loosely, some damping at that location. Something like a netting, otherwise when you place the LP straight, the damping might fall through into the enclosure. This should help tame the output.....damn, what a rumble !

regards,
Sunil

 

[cmsajith]

Latest update:

Two more panels to go...:yahoo:

 

[sunilj]

Nice going Sajith. I see you've also generously 'Fevicol' caulked the edge joints. Can't wait to hear the rumble.

 

[GeorgeO]

"Rumble" appears to be the operative word here, eh Sunil?

 

[t.antony]

Good work Sajith, it's coming out really nice. Are you planning to commission it on the new year party.... :thumbsup: ?

 

[cmsajith]

Nice going Sajith. I see you've also generously 'Fevicol' caulked the edge joints. Can't wait to hear the rumble.

Thanks.
Fevicol cannot expand as PL adhesives (~1/8") and I dont want to take the risk of sound leaking. So I am applying the glue as much as possible at the point of contacts and 2 thick layers as sealant (5kgs of fevicol used so far)

 

[cmsajith]

"Rumble" appears to be the operative word here, eh Sunil?

Will come to know once I drive it... I never had an experience of horn sub sound before..