My DIY Shiva X2 Subwoofer Build

[santhosh]

This thread is about my DIY Subwoofer Build. This is the first time I am doing an Audio DIY, so let us hope it works well. Though I have some carpentry tools, I am not very handy with wood. I have chosen a sealed design (no port) and the enclosure is 4 Cubic Feet.

The subwoofer driver that I will be using is a Shiva X2. Follow this link for more details. Ordered it from the US for $189 and spent ~ 9.5k for shipping through a service called Borderlinx using which you can ship anything from US or UK. I must thank DIY'er and friend George for the great deal. He bought one of these drivers as well.

Here are some pics of the driver:

Closeup view of the cone and magnet:

 

[santhosh]

The Shiva driver come with very good documentation and Kevin Haskins of Exodus Audio is very responsive to queries. He has put together some App Notes which I have considered while arriving at the subwoofer dimensions and volume. The subwoofer has been designed to fit in a particular corner in the room and the driver will face the rear wall with a gap of ~ 4inches.

Size of the enclosure is:
Length = 26 inches
Breadth = 20 inches
Depth = 18 inches

Using the Hometheatershack Enclosure Volume Calculator here, I arrive at the volume of 3.97 Cubic Feet. It is not uncommon to mention Volume of a speaker cabinet in Liters. Use the conversion- 1 cubic foot = approx. 28.3 liters and we arrive at a capacity of 112.3 Liters

Now that the dimensions have been locked down, I bought a MDF board of 19mm thickness and 8ft x 4ft in size. I got this transported directly to the wood shop and got it cut to size. I then got the cut pieces home and got the carpenter to cut the edges to have dovetail joints. These joints provide a very strong joint thus strengthening the cabinet.

Sides are being put together to form a box:

The box has been test-fitted together without glue as the braces have not been fitted yet. Braces offer reinforcement to the cabinet and are a must if you have a span of more than 14 inches.

The sides were then numbered the box was dismantled. The carpenter then made the marking for the grooves on the inner walls. The idea is that the braces will slide through the grooves and offer a tight fit - strength again being the reason for this design.

After marking the grooves, the grooves were then carved out

 

[santhosh]

Two pieces of mdf were joined to form the brace structure

Next the brace structure was test fitted

The brace structure was then removed and square holes were cut on three of the four wings. The fourth side was then cut in the shape of the magnet as can be seen below:

Here is another view (driver is not yet fitted, just a test fit). I will be adding another layer of MDF for the baffle (not seen in the pic)

 

[santhosh]

This is where I have reached thus far. Next step would be to deaden the cabinet. Suggestion on deading materials welcome.

Even before I started this build, I have been speaking to some DIY'ers (GeorgeO, Anilva, Rajiv, Suri, my friend Sunil, Kapvin, Soundsgreat, Anilkumar to name a few) and they have been very helpful in answering all my queries patiently. Thanks for that friends:thumbsup:. Much appreciated:cheers:. Will continue to check with you on this till the build is complete.

From now on until next 3 weeks, movement will be slow as I will be away on a training(from work) during the next two weekends.

 

[captrajesh]

Great work Santosh and fabulous pics. Keep them coming; I'm glued to this thread.

 

[vivek.saikia]

Thanks for sharing the pictures. The build is looking great. I bet the subwoofer will outperform any subwoofer of about 5 times it's price.

 

[prem]

Cool Santhol2.

 

[hemant0285]

Great going... keep updated... a DIY subwoofer shd surely giv u d tru HT experience...All the best...!!

 

[heliumflight]

Santhol2 your truly an enthusiast.:licklips:

--
helium
SB Classic> Beresford DAC 7510 MK4> Lyrita SET 2A3/ Sugden A21a> Highly modded Vintage B&W DM4 => MUSIC

 

[santhosh]

Missed adding these 3 pics.

I don't have a jigsaw [any suggestions on a VFM one that I can buy for future projects]. So, I got the circle cut at the same wood shop where I got the cutting of the MDF done.

 

[santhosh]

Great work Santosh and fabulous pics. Keep them coming; I'm glued to this thread.

Thanks Captain.

Thanks for sharing the pictures. The build is looking great. I bet the subwoofer will outperform any subwoofer of about 5 times it's price.

Thanks mate, I hope it sounds good. My first audio DIY, we'll know soon.

Cool Santhol2.

Thanks Prem.

Great going... keep updated... a DIY subwoofer shd surely giv u d tru HT experience...All the best...!!

Hemant, I am making this mainly for music. Plan is to use it for movies as well with a different EQ setting. For movies, I also plan to add a pair of ButtKickers.

Santhol2 your truly an enthusiast.:licklips:

Thanks buddy. Wow, I see a Sugden:licklips: in your signature. When?

 

[anilva]

Santosh,

Very nice build. Done with good care and detailing. I believe anything done this way, yields good results.

Also spend time in planning a great finish to the enclosure. That's where lot of people take it easy and people like Suri stand out.....

Cheers.

 

[sidvee]

Great work Santhosh - I'm sure it will be a kick ass sub. Back when I was doing simple DIY, parts express sold these vibration dampening sheets
Lightweight Vinyl Sound Damping Sheet 10" x 13"
that have various uses, specially lining the inside of cabinets. To my ears they appeared to work well.
Cheers
Sid

 

[CANDUU]

Congrats,You made it my man,strongly built monster .....
Waiting for the end result....
Hope it sounds better than ur expectation....
Finally u had ur words buddy.

 

[madhu_7]

Nice build Santhol i cant wait to see the end product.....Can visualize the amount of pre work and planning in it.

 

[vivek.saikia]

One quick suggestion though. If the cabinet is still not glued yet, then you can smoothen out the edges of the braces and make them rounded. This will help in reducing diffraction due to air turbulence inside the cabinet. No practical experience regarding this. Just suggesting from what I have learnt from various subwoofer build projects i have seen online.

 

[santhosh]

Santosh,

Very nice build. Done with good care and detailing. I believe anything done this way, yields good results.

Also spend time in planning a great finish to the enclosure. That's where lot of people take it easy and people like Suri stand out.....

Thanks Anil. I plan to give do it up in a Piano black finish similar to my post #9in link below (which inturn has a few links to a fantastic build on team-bhp).
http://www.hifivision.com/home-thea...388-mirror-finish-your-pc-case.html#post79357

Great work Santhosh - I'm sure it will be a kick ass sub. Back when I was doing simple DIY, parts express sold these vibration dampening sheets
Lightweight Vinyl Sound Damping Sheet 10" x 13"
that have various uses, specially lining the inside of cabinets. To my ears they appeared to work well.
Cheers
Sid

Thanks for the link Sid. Looks good, will do some more reading. A audio DIY'er friend of mine has used Tar sheets and is impressed with the results.

One quick suggestion though. If the cabinet is still not glued yet, then you can smoothen out the edges of the braces and make them rounded. This will help in reducing diffraction due to air turbulence inside the cabinet. No practical experience regarding this. Just suggesting from what I have learnt from various subwoofer build projects i have seen online.

I have read that smoothening the edges is a must for a port - to reduce port noise. Drawing parallels, I think you are right and I can still do it since I still have one side open.

@CANDUU: Thanks man

@Madhu: Thanks mate, you are welcome for a listen once I have completed the build

 

[Rajiv]

Hi Santosh,

Great work.

Thanks for sharing the build pictures.

I bet the sub will sound awesome.

Regards
Rajiv


P.S. What is the status on your phono cartridge?

 

[GeorgeO]

Looks like this sub will really kick serious butt! Seeing and listening to the sub that criss cross biult in Hyderbad using the Dayton Titanic I have no doubt that this will be another successful build. May the force (Oops.bass) be with you.

 

[grubyhalo]

Looks fantastic! Like suggested before, go for a nice finish for the monster. Maybe a rich dark metallic automotive finish?