Call me stuped, Throw together Sono. (1 Viewer)

[Joe Tilley]

Ok this may have been a little dumb on my part, so I wont take any offense if you all call me a moron. As some of you might know my 15" Dayton's spider ripped a couple weeks back & PE doesn't have them in stock. I sent in the sub & they gave me credit for it & would send me a new one when they arrived. But being the impatient person I am I ordered a 12" DVC to hold me over. I had been wonting to build another one anyway so I figured why not.
Any way I cannot for the life of me get any of the box design software to work on my computer for some reason. Every program I have tried will only come up with a half screen & I cannot figure out how to fix it or what is causing it to do this. So I just went out on a limb a threw a sono together for something quick. What I ended up doing was using a previous 16" sono cut to 38&1/2" inside cap to cap. It is ported using a 12" by 6" port & is stuffed using app 18oz of fill.
I must say I was pretty surprised with how it sounds. I figured it would just be a POS since I did just try out some dumb luck & had no idea what kind of tuning point it would be at. It by no way is comparable to my other sono ( witch is done right ) but it still has some damn good output. I have played quite a few of my favorite movies & cd's & it is very smooth with everything. I did do a sweep from my Avia disk & its really strong in the mid 40's to 30's & starts quieting down at around 28hz.
Anyway just out of curiosity can anybody tell me what kind of tuning point I ended up at. Like I said call me a moron if you wont, I was just more curious to see just what would happen if I made a stupid guess. I do intend to build a proper enclosure once I get my 15" back, I just wonted to have some fun wile I waited.

 

[Jake K]

WinISD says the tuning frequency is at about 32hz, with a big bump rising to over +5db at 36hz. Looks like a 30" port would have been a better choice. Not bad for a throw together sonosub though!

 

[Joe Tilley]

Thanks Jake, That would make since since it is at its strongest in the mid 30 to 40hz with my Avia disk. I don't know if I will or not but I may just play around with some different port lengths. I've got plenty of it to go around & it wouldn't be to hard to swap a few different ones in & out.

 

[Joe Tilley]

Ok now I'm curious as to what I can tune the enclosure to. With what I have, how long would I need to make the port to tune it to say around 20hz or a little lower if at all possible. Like I said before the sono is 16" & measures 38&1/2" inside cap to cap. I have all the 6" pvc I could ever need & it would be easy to pull out the shorter port & replace it. I have 35" of space from the driver to the top cap, but for what I understand with 6" you don't wont to go over (25"?)or you will start to get pipe resonance.
Thanks for any suggestions.

 

[Jake K]

Hello,
A 6" port tuned to 20hz would have to be like 42" long, but tuned to 23hz it would be 31", and 25hz at 25". I don't know about pipe resonance, what exactly is happening there?

 

[Joe Tilley]

Thanks again for the info Jake. Tomorrow I'm going to try out one at 25" & see what results I can get.

 

[Jake K]

No problem! I want to build an SVS 20-39 clone like that with a 17" long 4" flared port tuned to around 20hz, but the parts for my future AV15 sub ate up all my money!:frowning:

 

[Joe Tilley]

Well I put in a longer port today, 25". It didn't really change a whole lot. with Avia it still has a pretty strong hump in the mid 30 & 40hz region but it is defiantly a smoother transition there. Before it peaked rather quick & than flattened fairly fast as well. Now it is noticeable smoother into the mid 20's.

 

[Jack Gilvey]

My guess is that the hump is at least partly due to the room and not the tuning point. If you want to know the exact tuning, touch the driver lightly while running the Avia sweep (not sure how fast the sweep is), the point at which the driver motion almost stops is the Fb.
If you want to lower the tuning further, use a 4" flared port, that's enough for the 12" DVC.

Any way I cannot for the life of me get any of the box design software to work on my computer for some reason. Every program I have tried will only come up with a half screen & I cannot figure out how to fix it or what is causing it to do this.

Hard to believe every program gets the same "half-screen" error. Which ones? It would be good to try and learn to use at least a simple one if you're going to bother with the effort of building. If you've got a driver's license, you should be able to get this one working:

http://linearteam.dk/default.aspx?pageid=winisdpro

 

[Joe Tilley]

I did delete the programs I had, & reloaded WinSID & it is now working. But I don't completely understand how it all works. One thing I cant figure out is how to change everything from metric to inches. It says in the help menu that it can be changed but I cant find it anywhere.
I by no means am a computer person so that is part of my problem & I hate to admit it but I Suck at math which is my other problem. I guess I'm not the brightest person around but if you put a blueprint in front of me & give me the tools I can build anything you wont.
One thing that throws me off too is when one person describes something they will use liters, than someone else comes along & uses cubic feet, than someone else starts talking about 3ft< something something to pie = 6 something else. I cant catch onto all the different lingo. All my skills are hands on & I have some weird ways with math that get me by when I need to but all the different methods get me lost.
Anyway I will do some more looking at the WinSID program & see if I can figure it out ( hopefully ).

 

[Jack Gilvey]

...if you put a blueprint in front of me & give me the tools I can build anything you wont.

Cool, 'cus there's lots of stuff I won't build.

 

[Joe Tilley]

Thanks Jack, I figured out the measurements or rather how to change them. I Did try WinSIDPro again & its the one that is giving me trouble loading half cocked on my screen. WinSID works fine but I'm still confused on how to use it. How can you calculate for a sono instead of a box? Do you just have to do the math & convert the area of the sono verses a box?
I always thought that you could just load the driver & your desired goal & it would give you the necessary volume & dimensions ext. Or am I still missing something? I'm sure the answer is probably right in my face, I'm just not seeing it.

BTW, You said theres lots of stuff you wont to build. One of my favorite things to build with is fiberglass. Actually I have about 7 years experience with fiberglass molds & production. There is no limit as to what you can build with the stuff so it can get pretty interesting. I've been around just about everything from wood work, to building Boats & Street Rods. I was pretty much raised with a wrench in my hand watching & helping my Dad build his many different toys, I just should have paid more attion in school rather than worrying about building cars.

 

[Jack Gilvey]

I was pretty much raised with a wrench in my hand watching & helping my Dad build his many different toys, I just should have paid more attion in school rather than worrying about building cars.

The ability to build cars is certainly a more marketable skill than what most are taking away from college these days. I've had I.T. guys working retail for me for $9/hr. having just had their Saabs repo'd. Supply and demand.