Small Sonotube?

[dsanders]

I am new to the DIY thing so please forgive me, I am very open to learning though. Anyways I am interested in building my first speaker, right now I am leaning towards the sonotube approach for the simplicity factor and cost. I was looking on madisound and saw the Peerless 10" Woofer 831724 for $32 so I was thinking about getting that for my first project so I wouldn't have to much invested (I am a recent unemployed college grad). With an 18" wide sonotube cut at a little over 3 feet I get a volume of about 5.65. So I took that and plug it into WinISD and get a pretty flat response with an F3 of about 25hz (ported 4 inches, tuned to 26hz). I realise this is not neccesarily real world figures but it still looks good to me. For what its worth I am probably going to be using this with my computer for music almost exclusively. I just wanted to take a swing at it before tackling one for HT / Music for my main stereo. Thanks for any input,
David
PS Heres a link to the driver
http://www.madisound.com/831724.html

 

[Super]

Hello dsanders. I recently completed my SonoSub using a Shiva driver. Its quite large, but the output is easily the best I've ever heard in comparison to any commercial sub for less than a few thousand dollars.

You may have one problem with the Peerless driver however. Most drivers are not designed to be mounted horizontally, i.e up or down firing. If they are mounted in this orientation, gravity will take its toll, and the cone of the driver will begin to sag, ultimately destroying the driver. What you can do is make a sonosub, and then mount the entire cabinet horizontally. By taking two square pieces of material and then cutting out a hole for the exterior dimensions of the tube, you can make a simple stand for each end of the tube. I've even seen another piece of wood attaching the two "stands" together, and the entire contraption be used as a coffee table.

However, if you want to use this driver, you may be better off using a standard cabinet. If not, you could use the driver in a downfiring orientation, but it won't last a long time, and will need to be replaced prematurely.

If you'd like more information on my SonoSub, feel free to e-mail me or ask questions.

 

[tsz]

>Bryan
In what way is the Shiva driver optimized to be mounted horizontally?
I think it sounds rather strange.
if my calculations are correct the maximum force when the cone is moving 10 mm p-p at 50 Hz would be over 50 times stronger than the force caused by gravity, I've no idea but shouldn't the driver be able to handle the gravity then?
How do you tell if a driver can be mounted horizontally, stiff suspension?

/Tobbe

 

[dsanders]

Sonotube

I got to thinking I might as well wait until I have the space and $$$ for the Shiva Driver, I got to thinking it would really be only about $60 difference between the drivers and I would still have all the other costs so I really wouldn't be saving that much money. I would love any input on Shiva Sonotubes, I have read a pretty good bit but always open to more.

 

[Super]

For a description of my sub, check out the "DIY Stereo Subs" thread. It's either on the last page or near the end of the one before. I'd also recommend the AVA-250 amp from Adire Audio. Can't beat it for the money. Well built, has adjustable phase, crossover, and output level, and I haven't even been able to approach the max output level in a listening environment. I rarely use 1/3 of its output, even in movies. The Shiva is indeed a very fine driver. The sound is very tight and deep, beating all other Rel's, Carver, Mirage, and the Titan subs I heard, and when playing movies, well, the SPL's are so high that I thought the room was going to cave in. I even found "The Haunting" scary when the sub was on . And the rocket launcher scene in "Ronin", well, you know how the story goes. For the approx $400 bucks I paid for it (including amplifier!), I'd say it easily rivals or bests any commercial offering I've heard.

(Only once so far have I maxed the driver out, and that was feeding it approximately 2/3 of the power from the amp during a depth charge scene in "U-571". I could see the surround of the driver exceeding the 3/4 inch gasket on top of it )

Oh, and one more thing, I've got to commend the folks at Adire Audio for exquisite service. They notified me immediately that their products were on backorder, they shipped it out the same day that they arrived, and they even upgraded my shipping for free to 2nd Day Air. I'd definitely do business with them again.

 

[dsanders]

I'm thinking that is definately the route I will be going, last I can think of is how does it sound with music? Thanks,
David

 

[Super]

Tobbe: It's not designed to be mounted in any designated position, but it can be mounted horizontally. I don't think it sounds any different. The only thing that should make it "sound" different would be the floor or other object resonating which I don't have big problem with. I'd imagine the suspension plays a large part of it, but I'm not entirely sure. Its quite often specified whether it can or not.

David: I found it equally as good for music. This is another advantage of using the AVA-250 as an amp. It is very easy to "dial in" the sub using the phase and crossover knobs to virtually blend in as an extension of your mains, the way it should be. And you can adjust the levels to your taste. The Shiva driver goes just as tight as it does deep, and it gets better with time. At first, I found it to be a little slow, partially because the surround was still so stiff. After some good break-in time, the surround softens up (doesn't lose support, but is more flexible), and it effortlessly stays on pace with the music. When I said it rivaled ANY of the other subs I heard, this included some 10 inchers by REL, which are plenty tight in their own respect. This equaled if not bested those, and they cost well over $1000, and can't produce SPL's nearly as high as this sub can.

If you need some good tracks to break it in, try some tracks with organ music, or Fleetwood Mack's "The Dance" album. Also, pick some DVD's with particularly high punishment levels. Ronin, The Haunting, U-571, and Titan AE are some of my top choices in doing so.

 

[GRollins]

U-571 is deadly...better have someone check the structural rigidity of your house before getting depth-charged.
Bryan,
I keep threatening to drag the video stuff down into the dungeon where my system sits, with the idea that it ought to do a fair job at the front L & R channels, not to mention the .1 channel. The only thing that hangs me up is how to arrange for center and rear channels to match...

Grey

 

[Super]

Grey:

Of course its deadly! I wouldn't have used it to test with otherwise! As far as the rears go, I think it's definitely overhyped in regards to keeping speakers the same throughout. For the center, I'd agree, but for the surrounds, its of very little importance. Aside from some glass shattering or ambient music/talking in the background, well, I've found that its of no big concern. As for new formats, well, I'm not particularly fond of THX. Having a single speaker back there makes it too point-of-origin for my liking. What I did do was pick up some nice little Mirage floorstanders, and stick them in back with my OM-R2's. So now, including sub, I've got 8 speakers scattered around the room while still clinging on to the MAF (Mother approval factor) by the tips of my fingernails. Why 8? Well, who needs THX when you have DTS-ES?! Rather than a single speaker being in back, you have another two, spaced a few feet apart from each other. I find it to be definitely more natural, and, well, "surrounding" than THX, while still having the option to run them in mono for THX. Rent "Chicken Run" and pay close attention to the scene with the array of pilot lights, you'll know what I mean

(By the way, when I thought my driver was maxed out, it wasn't! Upon further inspection, it was the enclosure hopping up and down, with a little help from the floor resonating!)

 

[GRollins]

Bryan,
Like I said...have someone check to make sure your house is sturdy...
For better or worse, my video setup isn't matched front & back. There are few movies that make good use of the rear channels (The Fifth Element and Das Boot [you tried that one yet? another submarine movie] come to mind--I have high hopes for Star Wars I, due out a little over a week from now). The front speakers are my old Rogers LS3/5As, and the backs are an old pair of ADS 300c. No front center. Yes, I've got subs--four KEF B-139s (Geoff will know what these are, but not many other folks, I'm afraid). It's all cobbled together from the cast-offs of my main system; the ADS from an old car system. It works, but it's not top-notch. The whole video thing is fun, but not an obsession with me the way that music is.

Grey

 

[Super]

I've seen the Fifth Element a few times, but not with my latest HT equipment, and Das Boot I saw when we had the *gulp* HT in a box years back. I'll have to give them both a try.

As for the house being sturdy, well, my mother collects Department 56 houses which she has arranged in a nice curio cabinet which also happens to be in the room. During some scenes it rattles like no other, but during music it seems ok. In order to make room for the amps and to keep the other equipment cooler, I'll be constructing a rack this weekend (particularly because my Meridian transport is sitting on the floor, heh heh.) I'll be making a version of the Flexy rack with one or two customized shelves, and when I get the chance, I'll be making a sand trap platform for the transport. If that goes well, I'll make some more for the other equipment.

But I'm definitely having a problem with my computer, sadly. Under no circumstances can I move it, but it also happens to be no more than 3 feet from the sub, and is also located in one of my floor's "lively" spots. Spiking the computer helped somewhat, but those deep notes still cause some rattling, and the case seems to resonate badly in the 40 hz region. Any ideas as to how I can solve my problem?

 

[GRollins]

Bryan,
Time to think British...
For quite some time, the British made a practice of using (by American standards) thin-walled speaker enclosures, then damping the walls to subdue resonances. The ideal thing for your circumstance would be some adhesive bitumen pads to stick on the inside of the computer case. An alternate, and a cheap one, would be to use some of that gunk they spray under cars to deaden sound and protect against rust. Your local NAPA store will have something of this nature in a spray can.
The problem with either of these is cleaning up the case when it's time to resell the computer.
Something else you could try is a 1-2" slab of foam under the computer to absorb floor vibrations, although it won't do much for air-borne stuff. For obvious reasons, you don't want to block ventillation.
Hmmm, lemme think on this one a bit more. I'm having trouble coming up with good strategies that won't be messy. My usual response to rattles is to remove the offending item, but if that's not an option, we'll have to be more creative.

Grey

 

[Schaef]

Computer rattles

Computer rattles I can help with! First thing to try is, open the case and make sure every screw you can find is tight. Then put it back together making sure those screws are tight. If that doesn't completely rid the problem, then try to figure out what exactly is causing the rattle. If you take the case off, does the rattle stop? If so, then either the case is loose, or its vibrating against something or something is rattling against it. Narrow it down to what's rattling, and try small pieces of foam in the area. (Between screws and items, and things like that) If you can narrow it down some more, I might be able to help further.

P.S. - THX doesn't dictate one speaker in the surround, you might be thinking of Dolby Pro-Logic, which has the surrounds in mono. Dolby Digital and Dolby Digital EX both have stereo surrounds. THX just dictates what speakers to use and what amplifiers to use.

 

[Super]

Sorry for the misunderstanding, I was referring to the 7.1 THX format. As for the case, I will open it up an a bit and take a looksy. Just one concern though. Isn't it possible that the foam can create a static charge which could damage the circuitry? Thanks.

 

[Schaef]

No harm done on the surround front....

As to the static issue, not really... What I'm figuring you'll end up with, the foam will be in constant contact with both parts that are causing the problem. This way, there won't be a tendency to build up static, plus, most of the items that you would be doing this to should both be at ground potential, so no build-up again. (Unless of course you've defeated the earth ground on your computer, which in that case, there's more important things to worry about then...)

There's a bigger chance you'll deliver the deadly static shock than the little pieces of rubber you'll use to deaden vibration...