# Dual end tables for subs



## jszmgpolk

I have two end tables that I want to turn into subs. The dimensions of the tables internal will be 20x13x12 after internal beefing.. I figure i'll have around 50l after bracing and ports. I am unsure to go sealed or ported, 10 or 12 subs, and how much power to use. This will be for Home theater and music. The room is open on both ends and measures 15x15. Please help me design these subs.


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## Mike P.

50 liters is 12" sealed territory, The TRIO12 from CSS works well with 500 watts and a hi-pass filter would not be required.


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## jszmgpolk

Cool. Wasnt sure i would be able to go with 12s. How would the sealed enclosures do in Home Theater.


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## Mike P.

A pair will do well in your room size.


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## jszmgpolk

Why does my measurements look different than yours in Winisd Pro. When i select 300 or 500 watts the graph is the same and the qtc is different at 50l


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## Mike P.

Here's the Driver file:

View attachment CSS TRIO12.wdr


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## jszmgpolk

I cant seem to open the wdr file. Could you post the graph with the 300 and 500 watt signal please?


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## Mike P.

I uploaded the driver file, save it to the Drivers folder in WinISD. Use this file to create a project with a 50 liter box and 500 watts of input power.


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## jszmgpolk

Which amps would you suggest. I need this to be a single amp to power both subs.


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## Mike P.

The Behringer iNuke 3000 comes to mind with 2 x 880 watts into 4 ohms.


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## jszmgpolk

If I went with the inuke 3000dsp would this replace the need for the feedback destroyer


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## Mike P.

I believe it should.


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## jszmgpolk

So I am going to order parts this week. Mike, if I go with the inuke3000 or ep2000 I understand that I will not need a high pass filter. Is this correct? Also were are most people ordering the behringer amps?


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## fusseli

I would go with the inuke over the EP. Beware though, the flexibility of the inuke dsp is awesome, but I believe it has a built in HPF at 20Hz. I'm not sure if it's modifiable or defeatable, you'll need to double check that. Having it turned on would rob some of the rumbly fidelity of your nice sealed subs.

Edit: the inuke's HPF can indeed be turned off. You can play with the software without buying the amp http://www.behringer.com/EN/Products/NU3000DSP.aspx


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## jszmgpolk

Ok I have since purchased the bfd 1124dsp and will incorporate this with the subs. I had intended to not purchase the dsp so that leaves the ep2000 and the nuke3000. This is why i ask because want to make sure about the HPF. If I need i can just purchase the dsp and be done. Just want to make sure so I only purchase what I need.


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## jszmgpolk

So I have decided on the trio 12s and bash 500s amp. Amps are onhand but subs will ship Monday. In the meantime I hope the pix of the cabinets can be seen. The tables I used are the ends of an antique vanity that my wife let me destroy then rebuild.


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## fusseli

Wow, very nice :clap:


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## Mike P.

That's going to be a nice pair of subs!


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## jszmgpolk

Thanks Mike. Thanks for all your help. I will ask if you think I should add a hpf.


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## Mike P.

Are you using Bash 500 amps, one per sub?


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## jszmgpolk

Yes. One amp per sub.


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## Mike P.

The Bash 500 has a default hi-pass filter at 30 hz, it will need to be changed to 13.9 hz by soldering in two different resistors.


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## jszmgpolk

Ok. Win isd shows reaching xmax before that freq. But I trust you Mike. Thanks !


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## Mike P.

Are the cabinets 50 liters net volume?


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## jszmgpolk

Real close. Between 48~50l


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## jszmgpolk

Will I still need to set the hpf at 13.9?


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## Mike P.

You actually don't need one at all but 13.9 hz is the lowest the Bash 500 can be set at according to the documentation.


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## jszmgpolk

So that I understand. The filter fc is that the cutoff frequency of the amp? Will it not produce frequency below the filter fc?


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## Mike P.

It's assumed to be a 2nd order filter, it will roll off at 6 db per octave.


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## doublejroc

This is a very intriguing project! The fact that you saw use out of the old furniture, instead of tossing them away or selling or whatever.... Thumbs up!! Hope these pictures inspire others with the skills to complete similar tasks.


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## jszmgpolk

Thanks. I have been planning this for some time. Plus the furniture will blend and not be a sore to the eye. Our should I say the wife acceptance factor plus I get my dream subs.


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## jszmgpolk

So if I set the hpf at 13.9 hz I will have a boost plus more output correct? Also I am having a hard time locating the resistors on the board. Is there a how to video on the resistor replacement?


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## Mike P.

Yellow is 500 watts and no HPF, green is 500 watt and a HPF at 13.9 hz with 1 db of boost in the 20 - 24 hz range as stated in the boost tables. The difference is 2 db at 15 hz, nothing you would notice.










Resistor location is here:


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## jszmgpolk

More photos! Subs should be in hand Monday.


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## jszmgpolk

I got subs today and installed. However both subs are making a popping sound at low intense frequencies during movies at mmoderate levels. I did not install a hpf only what came stock with the bash 500s amps. It seems maybe the subs are reaching cone excursion. What advice does anyone have. This it's very frustrating any help would be appreciated. I am listening at the same levels as before with my 10 inch velodyne.


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## Mike P.

If you got the amps from CSS then send him an email and ask at what frequency the HPF is at.


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## jszmgpolk

I got the amps from PE. Do I need to mod the amps? I thought that with my setup I would not need a hpf. Also I an using the lfe position on the amps. I tried the internal but the same thing happens.


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## Mike P.

The TRIO12 in 50 liters with a HPF at 17 hz ( according to the P.E. site) shouldn't be bottoming out.


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## jszmgpolk

What does the p.e amp state that the hpf is set at before the modify? I have not modified the amp. No hpf.


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## dboff01

jszmgpolk said:


> What does the p.e amp state that the hpf is set at before the modify? I have not modified the amp. No hpf.


According to comments on the P.E. site, the HPF is now approximately 17 Hz by default, which is the sim results Mike P. just posted.


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## jszmgpolk

Well this is odd and sucks. Bothe subs are reaching xmax. The enclosures are tightly sealed. What to do?


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## Mike P.

Just checking, what are the internal dimensions of the cabinet?


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## jszmgpolk

11.5 x 14 x 27 minus sub.


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## Mike P.

The internal volume is 68 liters, not 50. The Bash 500 amp used to come with a hi-pass filter at 30 hz, it has been stated on the P.E. website by a customer who wrote a review the latest batch of Bash 500 amps have a 17 hz hi-pass filter. Even with a hi-pass filter at 17 hz, in 68 liters with 500 watts the sub is still under Xmax. I strongly suspect an air leak.


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## jszmgpolk

I was very careful when sealing the subs. I used caulk and a fiberglass sealer on the inside. When I push slowly in on the subs they slowly return. Or should they bounce back quickly from the internal pressure. One sub does however seem to scratch our rub on something when I slowly push in on it. No whistle of any kind and I misspoke on the height of the cab it is 24 inches tall.


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## Mike P.

Did you seal the drivers to the cabinet with any kind of foam weatherstripping tape?


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## jszmgpolk

Yes with 1/2 weather stripping sent from css. The amp is only sealed with the supplied seal tape that came with the amp. Should I get a better tape. The amp internals share volume with the box.


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## Mike P.

And the amp is well sealed?


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## jszmgpolk

I hear no leaks coming from the amp cavity. Emailed Mr. Remeir at css and turns out he is sending another driver due to some defective drivers. I described to him the scratchy sound I was hearing when I would push the drive driver slowly down. He said they thought they had eliminated the defective drivers but one slipped out. Great customer service! I will post when I get the new driver.


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## jszmgpolk

Got new speaker installed. Found air leak coming from plate amp. Sealed the cavity the plate amp was installed in. still having the same issues. I have used soapy water on cabinet and no air leaks now and the popping is still happening. Any suggestions?


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## Mike P.

Either somethings not right or you're over driving them. Do you have an SPL meter?


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## jszmgpolk

I do have a spl meter and tones. what do you suggest? I used audyssey for set up. The sub volume is set at the second hash mark on the gain. Receiver sub volume set at minus 4db. I also checked the sub volume after setup and the spl meter treads 78 to 80 db. It has to be the enclosure our me over driving them. because both drivers are doing the same. My internal deminsions are now 11.25 x 13.5 x 22 inches. Minus driver volume this is around 45l I think. It is just hard to believe that I am over driving them given the setup I listed. I am listening at the same volumes that I always listen at.


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## Mike P.

Do you have a correction file for your SPL meter?


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## jszmgpolk

I do when using rew through my laptop.


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## Mike P.

What SPL can you get at 20, 25 and 30 hz measured 3 feet away from the sub?


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## jszmgpolk

It will be awhile before I can run the test but I'll let you know.


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## jszmgpolk

Well Guess I was over driving the subs. I turned the amp gain down and have not experienced the popping. I guess I was expecting more. Makes me wonder if I should build new enclosures and port them.


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## Mike P.

If you went ported how big can the cabinet be? (external dimensions)


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## jszmgpolk

Well I would want to build two so I would want to keep it reasonable. 30 x 18 x 18.


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## Mike P.

30 x 18 x 18 would be about 108 liters internal volume if using a slot port 16.5" wide (the full internal width) x 1.25" high x 32.5" long.The length includes the thickness of the baffle. You'd get big gains in the 17 - 30 hz range compared to what you currently have.


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## jszmgpolk

Received my mini dsp and installed. Set the hpf @ 20 hz and all is good. Im sure this only hid the problem but at least I can enjoy the subs until I decide to build new cabinets.


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