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Discussion Starter #1
Hello,

In an attempt to achieve nice deep clean bass and still keep a high SAF :praying:, I was brainstorming some different enclosures. The main problem I have is it must look good and not stand out too much!

I thought why not make a wine barrel into a subwoofer? :clap:
PROS:
  • Looks great varnished up
  • Decent internal volume of 225L (standard barrels)
  • Overall good shape to avoid panel resonances
  • Around 22 to 27 mm thick sidewalls and end caps of Oak
  • Not too expensive at around $80~$130 AUD for the barrel
CONS:
  • May not be fully sealed due to dry wood
  • Would need to beef up and attach fatter end caps (baffles)
  • Hard to brace if this is required
  • Metal straps may rattle?
  • Access during construction fairly poor
  • Might be tricky to recess the plate amp due to the curved surface
I was thinking a Shiva-X powered by an OAudio 500w plate amp.
Probably ported down really low (14~18hz) with dual 4" ports tuned as low as possible while keeping port resonance in check. The OAudio plate amp subsonic filter board will need to modified to remove boost but I'm comfortable doing this.
Should I look at using a sealed Tempest-X instead.
Are there any other good quality subs obtainable around the same price in Australia?

Usage breakdown is 80% HT and 20% Music.
SQ and extension is preferred over SPL.
Target room is open plan, not well sealed and approximately 6m (W) x 4.2m (D) x 2.8m (H).

Is all this a viable? Am I missing any flies in the ointment?
Is there anything fundamentally wrong with using an old wine barrel as an enclosure for a subwoofer?
 

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First of all ...Welcome to the forum :wave:

CONS:
  • May not be fully sealed due to dry wood
  • Would need to beef up and attach fatter end caps (baffles)
  • Hard to brace if this is required
  • Metal straps may rattle?
  • Access during construction fairly poor
  • Might be tricky to recess the plate amp due to the curved surface
This will be interesting ...I'm sure the experts will help you get it done.

I just buils a Sonosub using a Sonotube (paper tube); and I think you don't need internal braces.

To fully seal it, maybe you have access to something in Australia, here in the U.S. there's a product to repair roofs (black tar) that I'm sure it can seal the dry wood.

For the caps, maybe you can add another layer of wood and make it 1 1/2" thick (at least where you will install the dirver).

Can the metal straps be glued in place with silicone or something to prevent movement???

You don't really need access to the tube (mine was 61" and didn't have problems attaching the insulation).

I don't think the amp will be a problem (I've seen some sonotubes with those amps), or maybe you can use an external amp :yes:

Good luck
 

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Welcome to the forum! This has potential to be a great looking subwoofer. Be sure to post pictures when you get to it!
 

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Discussion Starter #5
Hello,

First of all sorry about the picture heavy long post.
I've modelled the two basic options I'm looking at for the moment in WinISD.
Please note the sealed box has a box absorption factor of 5 and the vented has 100.
All graphs are modeled using the worst case (maximum) 500w input signal.
I have also applied a subsonic and low pass filter to each design.







Does this look reasonable?
Room Gain should flatten this out quite well I think?
Is the port resonance too low for a 4th order crossover at around 80hz?

I was thinking of using some left over bathroom waterproofing membrane to seal the inside of the barrel. It is quite hard but still a bit rubbery.

Any other ideas?
 

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This sounds like a really unique project. What are the "baffle" dimensions of the wine barrel? , what are the overall dimensions?

Can you fit an IXL 18 in the bottom? That probably be a better fit for that sized sealed box over a Tempest X.
 

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Discussion Starter #8
External dimensions are:
Diameter top and bottom: 540mm
Diameter in the mid section: 680mm
Distance between baffles: 900mm
Weight: ~50kg :unbelievable:
Internal volume without thicker baffles: 225L
 

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Discussion Starter #9
Cheers for the input.
A Mach 5 Audio IXL 18.2.2 sealed would fit fine... What would sound best?
I'm not familiar with the IXL 18's. Do the IXL 18's produce nice clean bass?
The IXL 18 would fit ported too... I'm not after loads of SPL, but I do appreciate a sub on the ragged edge will not be anywhere near as linear as a sub just cruising along.
I'll have a play in WinISD and have a look.
 

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50kg?:dizzy:

If you did want to go sealed you could fit an IXL 18 in there easy. I wonder if you could squeeze a ported 15" in there?
 

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Discussion Starter #11
OK,

Iv'e done some more modeling in WinISD.
Like last time, all graphs are done at maximum power of 500w which will not be for normal listening.
I have added subsonic and low pass filters. I have included their effects in the group delay graph this time. Sealed boxes are modeled with an absorbtion factor of 5 and ported boxes have a factor of 100.
The ported boxes have about 20l less space which taken up by port volume.

If the IXL 18 was ported I would put its ports just below where I will recess the plate amp.












First of all, am I modeling everything properly?
It is interesting to note that the Tempest-X (15") is pretty much on par with the IXL 18 with SPL!

Most of the group delay is introduced by the filters not the speakers! Is the amount of group delay shown here acceptable? The OAudio amp has a variable phase control, so will I'll be able to dial out the first 10~11ms of group delay across the board?

The room has wooden floors and plaster walls and has some large openings to other rooms, so I suspect it will only produce moderate room gain.
I would like to start purchasing the amp and drivers soon. :demon:
What driver would be best in this application?

Thanks for all your help in advance!
 

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Something doesn't look right with the sealed IXL 18 model. When I model it it has a 1 or 2db advantage across most of the bass range over the Tempest X. A couple of other things is that I don't think it's realistic to port the IXL 18 in this size of airspace. you can't get enough port area and volume to tune it low enough. You could port a SDX15 or IXL 15 well though and gain a few db over a Shiva X.
 

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Discussion Starter #14 (Edited)
Thanks for the help! I'm going to agree with you about the IXL-18 in a box this size with low tuning. Just not big enough... I would need the monster size wine barrel of 330l :rolleyes:, unfortunately this has a significant impact on the SAF!

Just a note for people skimming. The rest of this post is nearly completely wrong. Please read further on for why.

You may not be able to get the same results because I am using an Le value of 2.09mH for the IXL-18. That combined with the low 0.9mH inductance of the Tempest-X and its extra excursion, go a long way. I will also mention the filters and the box absorbtion factor of 5 representing a heavily stuffed box.

Correction: I have modeled the IXL-18.2.2 with an Le of 2.09 but in fact through some shady other specs I've found it is 6.09mH @ 1Khz which makes it model even worse!

The big problem is that I'm an Aussie and it's hard to get decent drivers over here at a reasonable price! I'm all ears on suggestions for good drivers in Aus for less than AUD$350. Our dollar aint worth much at the moment, and then there is shipping and customs :huh:
 

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Discussion Starter #15 (Edited)
Here is a comparison of the IXL-18.2.2 driver modeled in WinISD with all things equal except for the inductance values. It is unbelievable how much difference it makes! :yikes:
My mistake, I have the box size completely wrong for the sealed box!



The two to the left have no inductance values filled out (Le). The two to the right do assuming this site is right: http://www.soundsolutionsaudio.com/zencart/index.php?main_page=product_info&cPath=2_18&products_id=12

There are a few other references around stating IXL-18.2.2 Le of 6.09mH as well. This value has been pointed out to be clearly wrong. Please read the post two down from here and my apology later on.

I cannot source the IXL-15.2.2 into Australia. :thumbsdown:
Maybe I should go back to my Shiva-X ported nice and low idea?
 

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I'm sitting about 25 yards from a 200 acre Cabernet vineyard up in Napa county atm...... I like this idea, I say go for it!

just caulk the inside, it will be fine, you don't need bracing, those things are pretty sturdy. Here is another thought, design a nice wood rack for the barrel and lay it horizontal and then do two side firing woofers. This will give you the most for your money!
 

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Thanks for the help! I'm going to agree with you about the IXL-18 in a box this size with low tuning. Just not big enough... I would need the monster size wine barrel of 330l :rolleyes:, unfortunately this has a significant impact on the SAF!

You may not be able to get the same results because I am using an Le value of 2.09mH for the IXL-18. That combined with the low 0.9mH inductance of the Tempest-X and its extra excursion, go a long way. I will also mention the filters and the box absorbtion factor of 5 representing a heavily stuffed box.

Correction: I have modeled the IXL-18.2.2 with an Le of 2.09 but in fact through some shady other specs I've found it is 6.09mH @ 1Khz which makes it model even worse!

The big problem is that I'm an Aussie and it's hard to get decent drivers over here at a reasonable price! I'm all ears on suggestions for good drivers in Aus for less than AUD$350. Our dollar aint worth much at the moment, and then there is shipping and customs :huh:

Shady? Not sure what you are referring to, but I was open and forthcoming enough to measure the IXL-18 at 100Hz reference frequency. Now, you challenge anyone else to apply this test to any other driver and I will guarantee you that the measurement will *not* be the same as their posted values.

If you want to compare apples to apples, the measured Le for the IXL-18 at 1Khz is ~3.2mH. Plug that number into your modeling software and see what you get. I can even get you an Le measurement at 10kHz which is another standard reference frequency.

Wow. I can't believe the hair splitting that goes on around these forums.:dumbcrazy:
 

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MarkDN,

Something still does not look right in your graphs. The sealed box you showed for the IXL with no LE is only 106.73 L and the one with the LE added in is 205L. 6.09mh seems a bit much also. Where is this spec coming from?

This is what my modeling looks like for the IXL18. The RED trace is Tempest X with LE. Blue is IXL with no LE. Green is IXL with 3.2mh LE. All 3 are with 500w sealed in 205L and shown xmax limited. No HPF or LPF added.




 

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Discussion Starter #19
Hello Mrogowski,

Firstly I apologise for my prior post. After re-reading it, it was clear that it could quite clearly be interpreted as a slander against the Mach 5 Audio IXL-18.2.2 driver and Mach 5 Audio in general. :doh:

To set the record straight, I must point out that I am impressed with the incredible bang for buck the IXL-18.2.2 represents! If you can have a nice big box, which pretty much all 18" subs need, then it's a bargain! My use of the word Shady was regretful. :rolleyesno: My real intent was to convey the fact that the inductance (Le) value was not specified at the Mach 5 Audio web site, and that I obtained the value from an unverified and less reputable source!

I must state however that the inductance value is important when modeling as my prior post demonstrates. Whether this would translate into the real world? I don't know to be honest. My guess is there are probably bigger fish to fry like BL non-linearities, voice coil temperature, etc. In my opinion these are much more likely to skew results. So yes I admit it! I am a hair-splitter, nit-picker! :dumbcrazy: In the end all I want to do is pick the best driver for my needs for a 225L wine barrel.

Thank you for your input here and I am grateful that you have cleared up the IXL-18.2.2 inductance parameter value for me.

It is what I am trying to achieve with limited enclosure that is the limiting factor here not the driver.
It's Hoffmans iron law that's giving me grief.

My initial goal was not SPL but good deep extension with good SQ. These are things the IXL-18 can provide just not in a small enclosure that is more suited to a 12"~15" sub.
 

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Actually the IXL can provide extended low bass in this size enclosure if it is sealed and EQ'd. As we've already discussed, ported it is not enough airspace. It's not really enough for the Tempest X ported either.

I believe that your best bet may be a ported 15" with the airspace and 500w that you have available, but I'm not sure exactly what you have available there. What 15 and 18" drivers do you have access to? You said that you can't get the IXL 15"? What about CSS, or Soundsplinter drivers?
 
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