My DIY Shiva X2 Subwoofer Build

[vin_eme]

Hi Friends,
My subwoofer is almost done, just waiting for an amp. Both the amps I short-listed are out of stock:

Option 1: Elemental Designs: Car Stereo, Home Speakers, Electronics (Back ordered)

Option 2: O Audio - 500W BASH Subwoofer Amplifier (220V version is outta stock)

I am looking for subwoofer amplifier options. Need an amp of 1000 watts @4 ohms but atleast 500 watts. Preferably Class D or Class G.

I am also open to the idea of using a good Pro amp but prefer to buy from India to save on shipping. If anyone knows of a DIY kit, kindly share. Will consider that too.

PS: Have posted a wanted Ad in the Classifieds section as well.

Hey Santhosh, my visit to your place is still pending . Just saw few of Behringers which might suit your needs. BEHRINGER: NU1000
Or you can consider A500 in Bridged mode . I do have A500 with me with 220v conversion done. I need to test that. So let me know.

cheers,
Vincent

 

[santhosh]

santhosh,

both the amps are very much same. Except, the rack version has subsonic and bass boost filters. Both are defeatable and in addition to parametric eq.

although you may need more than one parametric filter, depending upon your room modes, so feedback destroyer may be needed in future. Just grab it when you find it for very cheap.

I guess I'll go for the rack mount then. Also, too many people have reported quality issues with the Plate amp version. The shipping is a killer, coming up to almost $200 + when I tried the Borderlinx calculator :sad:.

Hey Santhosh, my visit to your place is still pending . Just saw few of Behringers which might suit your needs. BEHRINGER: NU1000
Or you can consider A500 in Bridged mode . I do have A500 with me with 220v conversion done. I need to test that. So let me know.

cheers,
Vincent

Hey thanks Vince, let us try and meet this weekend buddy. Would be good to get your impression on my recently build A7s too . Yup, we could test the Behringer A500 on the sub, seems to have enough headroom. In bridged mode, might make a Kilowatt @4ohms?

 

[navin advani]

Option 2: O Audio - 500W BASH Subwoofer Amplifier (220V version is outta stock)

I like this amp.

I guess I'll go for the rack mount then.

Will shipping a rack mounted amp be cheaper than a plate amp?

 

[santhosh]

I like this amp.

Thanks Navin, I have written to Oaudio asking when they'll have 230V in stock again.

Will shipping a rack mounted amp be cheaper than a plate amp?

The rack mounted version is heavier and bigger in dimesnion, so more expensive to ship. However, I noticed that the plate amp version has a lot of quality issues. So better to stay clear?. See reviews here.

 

[navin advani]

Thanks Navin, I have written to Oaudio asking when they'll have 230V in stock again....However, I noticed that the plate amp version has a lot of quality issues. So better to stay clear?. See reviews here.

Yes I know Dayton's plate amp has had some issues. However there are few if any issues I have heard of the Bash 500W amp. The 230V version is available I think. Just ask. If not it should be available in a few weeks. I know the websit says out of stock but these guys often dont update their websites daily.

 

[santhosh]

After a long break, I have some updates to share on my build. The sub is now functional and needs some work on the aesthetics. Most likely, I will use a matte finish laminate to match the black ash finish of my ATCs.

So, since last week, I started working to complete the subwoofer as I managed to find a Behringer A500 (bought from member Vin_eme) to drive the Shiva. Out of 6 sides, only one side was pending and had to be sealed after filling the cabinet with Polyfill. Since I have been learning my wood-working ropes, I decided to give complete this on my own and I did .

First I lined the walls with Anutone Synth, then started filling with Poly fill which is used in pillows:

The subwoofer is closed to 4 cubic foot in capacity and consumed 3 pillows full of Poly fill (very close to the recommended fill of 48 oz per cubic feet):

The lid also lined with Anutone Synth:

Applied fevicol on tapped the top gently so it locked itself into position into the dovetail joints:

Made some markings so I could fasten the lid tightly using screws

With my trusty drill, I fastened the lid with self tapping screws:

OMG!! Why so many screws? Typical problem with DIYers, tend to over-engineer

For the baffle, I used a double layered MDF which I had glued together and used D-nuts on the inside. So, I fitted the Shiva Subwoofer with an Allan Key:

Almost done, just need to make the connections to the amp:

Here it is, alive and rocking the house!! (ignore the wiring on the left, been doing a bit of CAT6 networking recently)

I am very happy with the sound outcome, need to work on the aesthetics next. BTW, the Behringer A500 amp is a powerful amp and makes 600 watts per channel @8ohms in bridged mode. But IMO it still lacks the drive and headroom that the Shiva requires. I also noted that Behringer does not publish output specs for 4 ohm in bridged mode and some reviews also said it does not like a 4 ohm load. Nevertheless, it is gonna stay in my Home Theater System. Plan is to use the Behringer for a while and buy a Face Audio F500TS in the near future. The Face Audio F500TS is a superb amp and stable to 2 ohm. So, I can try powering both the Voice Coils in the Shiva X2 in parallel. Currently, I have wired it in series. Check out the amazing spec on the Face Audio F500TS:

http://www.diycable.com/main/product_info.php?cPath=146&products_id=670

 

[bibin3210]

Nice work......Is there any specific reason for joining the back panel using Dovetail?

Thanks,
Bibin

 

[gobble]

Wow some serious attempt at DIY there. :clapping:
Since it is sealed why didnt you go for glasswool?

--G

 

[captrajesh]

After a long break, I have some updates to share on my build. started filling with Poly fill which is used in pillows:

The subwoofer is closed to 4 cubic foot in capacity and consumed 3 pillows full of Poly fill (very close to the recommended fill of 48 oz per cubic feet):

The lid also lined with Anutone Synth:

Congrats Santhosh. I have a couple of noob questions.

1. The whole airspace of the enclosure is filled with polyfill!! Where is the driver located? Does the cone have enough free space to move back and forth?

2. Is the Anutone Synth for damping the cabinet walls? If yes, could you post a pic showing the same and also mention the cost?

 

[santhosh]

Nice work......Is there any specific reason for joining the back panel using Dovetail?

Hi Bibin,
All panels are joined using dovetail. The back dovetail on the back panel stands out because:
1) It is fresh
2) I have been clumsy hyeah: . The sub was largely made by my carpenter about a year or so ago. Last few months, I have learnt a bit of wood working and mustered the courage (and a bit of skill) to do the the last panel

Wow some serious attempt at DIY there. :clapping:
Since it is sealed why didnt you go for glasswool?

I had half a mind to go for glasswool and I had some stock at home, but decided to go with Polyfill as I was following the application notes that Kevin Haskins of Exodus/diycable had put together. Also, I have had good results with using poly fill in my A7 build, so....

 

[santhosh]

Congrats Santhosh. I have a couple of noob questions.

1. The whole airspace of the enclosure is filled with polyfill!! Where is the driver located? Does the cone have enough free space to move back and forth?

2. Is the Anutone Synth for damping the cabinet walls? If yes, could you post a pic showing the same and also mention the cost?

Thanks Captain, the driver is located along the left panel in that pic (though not seen in that pic). Though it looks full, it could take some more poly fill if one had to. The NRC (Noise Reduction Co-efficient) of Polyfill is such that it absorbs the mids and higher frequencies and allows the sub to go lower. It allows air to pass through it albeit at a slower rate fooling the driver to think it is in a larger enclosure. As per the app notes, the recommended fill was 48oz of poly fill per cubic feet. Did the math and thats 3 pillows (Kurlopillo brand) full for my ~4 cubic feet enclosure :clapping:.

The Anutone Synth was from my home theater build. I am not so sure about the current pricing of the Anutone, but my guess is around Rs.50 per square feet for 50mm thickness.

Here's a pic of Anutone Synth from my A7 build:

BTW, I have set the crossover in my Emotiva at 80 Hz and have also EQ-ed the other channels, so the summed signal of all channels below 80Hz is also sent to the sub. I have only tried it in my HT, yet to try it for music in 2.1.

 

[cmsajith]

Congrats and a nice build. I think you had 2 12" drivers, are you running twins in your HT? Expecting a few lines on the performance.

Filling the box can change the effective box volume thereby the tuning freq, hope you had rechecked the effective tuning of the box with some sub box app.

 

[ShaQ.Blogs]

Had the opportunity to visit Santosh's place while he was doing the sub. Since I am exploring the option of DIY I thout i'll have a look at how it has come out for him. The sub looks good. I havent heard it yet, looking forward to it

He has some really good speakers. The bookshelf that he showed me were terrific!! he's got a dedicated room, and man, he has done quite some work on it. I wonder how long it took to get it done.

Santosh...I see that impedance in parallel is 1 ohm. would be easier to supply power driving in parallel than in series. Is there a reason why you are trying to drive in series?

When In parallel, not sure which amps are capable of driving 1 ohm loads. The crown XLS models which we discussed specify 2, 4 and 8 ohm. I am suggesting parallel, cos you could explore option of second sub and even out room response and use one channel each from the amp for each sub.

The XLS 1000/1500 both should be able to drive this, drivers in series, bridged mode.
Let me know if you are looking to buy the Crown, maybe we could try bargain buying 2

 

[santhosh]

About Polyfill use, here is a link to an informative article that I had bookmarked: (Read Post#2) DIY Subwoofer Building, Repairing, & Upgrading - Blu-ray Forum

Congrats and a nice build. I think you had 2 12" drivers, are you running twins in your HT? Expecting a few lines on the performance.

Filling the box can change the effective box volume thereby the tuning freq, hope you had rechecked the effective tuning of the box with some sub box app.

No mate, I have only one Shiva 12" driver. If I'd only have known that this legendary driver will no longer be available, I would have bought two .

About checking the effective tuning with a software, I had done this when I initially decided on the dimensions (about a year ago). IIRC, the current alignment with the Shiva driver should go fairly low, into early twenties in-room. I plan to measure and tweak it further, but that will have to wait until I get a bigger amp. The Behringer will still be around, will run a few bass-shakers or butt-kickers hyeah:

Had the opportunity to visit Santosh's place while he was doing the sub. Since I am exploring the option of DIY I thout i'll have a look at how it has come out for him. The sub looks good. I havent heard it yet, looking forward to it

Thanks ShaQ, you are welcome mate.

He has some really good speakers. The bookshelf that he showed me were terrific!! he's got a dedicated room, and man, he has done quite some work on it. I wonder how long it took to get it done.

Those bookshelves you listened to were ATC SCM-11. Glad you liked it and the dedicated room . The room took me about 5 months including the civil work (that room did not exist earlier).

Santosh...I see that impedance in parallel is 1 ohm. would be easier to supply power driving in parallel than in series. Is there a reason why you are trying to drive in series?

When In parallel, not sure which amps are capable of driving 1 ohm loads. The crown XLS models which we discussed specify 2, 4 and 8 ohm. I am suggesting parallel, cos you could explore option of second sub and even out room response and use one channel each from the amp for each sub.

The XLS 1000/1500 both should be able to drive this, drivers in series, bridged mode.
Let me know if you are looking to buy the Crown, maybe we could try bargain buying 2

I will definitely wire the dual voice coils up in parallel, when I have the right amp. That Crown XLS1500 details of which you sent me....was a great find, never knew there was a shop dealing in this kind of stuff that too in a shop near to my house. I'll have to wait a bit longer before I am ready to spend on the sub again .

 

[vin_eme]

Excellent build Santhosh. Even the more eager to see all your setup. Congratulations! Hope the outer finish will also be done soon !..

cheers

 

[sachu888]

Nice build Santhosh.

Regards,
Sachin

 

[pdhanwada]

Santhosh,

Good job. I guess This is first DIY after your room treatment. Lot of fun in DIY.

Enjoy

Thanks

 

[sud98]

Congrats Santhosh.

Once you are ready I can get your auralex sub isolator, its lying packed now waiting for its rightful owner

 

[santhosh]

Santhosh,

Good job. I guess This is first DIY after your room treatment. Lot of fun in DIY.

Enjoy

Thanks

Thanks Pandu, this way my first speaker DIY but it took a little longer than planned. I started and completed a few other Projects while this was on hold. Sure is fun

Congrats Santhosh.

Once you are ready I can get your auralex sub isolator, its lying packed now waiting for its rightful owner

Thanks Sudhir, not urgent as I have another which I am currently using. Definitely reduces structural vibrations.

Some pics:
Have turned it around to face the listening position, sounds much better this way. I have also placed it on the Auralex Gramma Subwoofer Isolation Platform that I had bought last year.

Behringer A500 Amp

Like the way it gels with my system with all those blue LEDs etc

Here's a pic shot from mid-room showing location of sub w.r.t rack: