sonotube tuning......14hz??

**Jodean** · **04-06-08, 10:52 AM**

I just got done reading most of the LLT explained thread and was noticing that if you make the tuning freq down in the 10-15 hz range you will more than likely not need a eq and it may sound better will the rolloff lower and the port resonance will be higher at some 150-190hz which can be fixed by setting the low pass at 80 or 90hz.

I found the sonotube program in the article and entered my data into it.

Should i tune it to 14.2 hz with the 3' 8" port?

Sono length is already cut and its the newer tempest x which im not sure the program has....it just says tempest

**Mike P.** · **04-06-08, 09:00 PM**

The new Tempest-X is different from the Adire Tempest. The recommened volume for the Tempest-X is on the diycable.com website.

**thomas2717** · **04-07-08, 09:19 AM**

Hello:

Attached is a txt file of the TempestX param's (the forum does not allow me to upload sno files). Just change the file extension to '.sno' and I think you should be all set. Hope this helps!

[hint: open the file in notepad, goto file save as, and under files as type change to 'all files' and type .sno at the end of filename ]

**Jodean** · **04-07-08, 12:01 PM**

Im completely lost

ok i dont know what a sno file is and the volume of the sonotube is already set. I changed it to .sno but now what?

I thought i could change the length of the port to tune it deeper?

I thought the sonosub parameters would be close enough using the tempest.

I dont know what your talking about with the recommended volume because ive already made the sonotube 5' 3.25" long. So it really doesnt matter what is recommended.

Are there values i can input into sonosub or something?

Ive went through eveything at diy cable already......what length should i cut my port?

Do i need a differnt program?

**thomas2717** · **04-07-08, 12:55 PM**

'.sno' is the file format that the sonosub program creates and saves to your computer for future use - should you choose to save it.

volume of the sonotube or enclosure is different from the 'volume of air' displaced by the subwoofer.

The parameters vary and to obtain the best result and tuning, it is best to key in the different values.

I tried plugging in the values and have enclosed the jpg file. I think you need a port length of 45" to get a tuning of 14hz. (Hope some senior shackster can confirm this).

Play around with the sonosub program, clicking on the
'driver' button on top allows you to change driver parameters,
'endcaps' button allows you to change options for endcaps n so on.

Hope this helps!

**Mike P.** · **04-07-08, 01:58 PM**

What is the diameter of the port? In the first post you mention 8 inch but your attachment shows 6 inch. Remember that the maximum port length should be 36 inches or less, due to port resonances. If your port is 6 inch diameter, a 36 inch length will tune the sub to 15.5 hz.

**Jodean** · **04-07-08, 05:14 PM**

Quote:

Mike P. wrote:

What is the diameter of the port? In the first post you mention 8 inch but your attachment shows 6 inch. Remember that the maximum port length should be 36 inches or less, due to port resonances. If your port is 6 inch diameter, a 36 inch length will tune the sub to 15.5 hz.

The post shows 6" port on the diagram and i was choosing to go 3' 8" with the port which sonosub came up with on its own went i changed the hz to 14.2, sonosub had warnings and didnt warn of a 3' 8" port as being a problem.

I tried to open the sno file with sonosub but it doesnt work. (EDIT: ok now i tried again and it opened it.....)

So its not ok to have a 3' 8" port?? or is that a rule for square built boxes?

I plan to put a 1" radius flare on each end of the port.

**Mike P.** · **04-07-08, 05:59 PM**

Doesn't matter what shape the cabinet is, you want your port length 36 inches long maximum. In your design of 223 liters net volume, a 6 inch port 36 inches long will tune it to 15.5hz and a 8 inch port 36 inches long will tune it to 20hz. To tune the sub to 15 hz with a 8 inch port, it would have to be 70 inches long, which is unacceptable.
Here is an online calculator from Precision Ports, it will make it easier for you to find the proper port diameter and length for a given volume.

http://www.psp-inc.com/

**Jodean** · **04-07-08, 10:24 PM**

ok ill go with 36" then 15.5 is good enough

**SteveCallas** · **04-11-08, 07:31 PM**

223 liters with the Tempest X and a 15hz tuning? I think you may want to model this, as the results don't look very good.

I like 500 liters with an 8" port that is 28" long.

**Jodean** · **04-11-08, 07:55 PM**

Quote:

SteveCallas wrote:

223 liters with the Tempest X and a 15hz tuning? I think you may want to model this, as the results don't look very good.

I like 500 liters with an 8" port that is 28" long.

Ya ok, its already bigger than i am. Not going to happen. Sounds great so far and really goes down low. Ive hooked up a stand alone x over and set it to 50hz. It also has 90hz but thats almost too high and get overbearing at times.

Theres hardly any air coming out of the port at full excursion as is.

I have no idea and have never "modeled" anything and didnt have time to figure it out as i was building it now. I went with a design that was already done and proven.

**Mike P.** · **04-11-08, 11:10 PM**

As long as you're happy with it! Will you be updating your build thread with pics of the finished sub?

**Jodean** · **04-12-08, 12:02 AM**

right now i have everything just sitting by gravity....waiting for binding posts and router bit to flare the port. I have not glued the end caps on yet and have makeshift feet. The port and top cap are just sitting in the tube. Once i have it glued together ill be able to move it around but where it is now seems pretty good and peaks at my chair. I have a plan to lay it on its side to accomadate the bookshelves that were in design before the sub idea came to mind but i dont know if a sonosub will work laying down. If it does ill just leave it unfinished cabinet and build the bookshelves over it with doors of acoustic material.

sub as is, not glued together yet, no binding posts or feet. Old klh cube sub and new sonosub in corner powered by sansui and car x over set at 50 hz.

theatre room

**SteveCallas** · **04-12-08, 11:27 AM**

Quote:

jodean wrote:

Ive hooked up a stand alone x over and set it to 50hz. It also has 90hz but thats almost too high and get overbearing at times.

That's because of the resulting FR which you would have noticed from modeling a simulation....

Quote:

I have no idea and have never "modeled" anything and didnt have time to figure it out as i was building it now. I went with a design that was already done and proven.

Fair enough, you get out what you put in. Glad you are happy with it. May I ask where this was listed as a proven design?

**Jodean** · **04-12-08, 01:35 PM**

Not sure what you mean...i built this sonosub with dimensions from another guys sub. He used a 28" port and im using a 36" port which can still be cut shorter.....since i havent glued anything together yet. If theres something i should know just say it instead of saying it sucks. Tell me WHY you think this and WHAT you would do different. Again i cant change the sono diameter or length, they are set. All i can really change as of now is the port length.

I have no idea if you modeled this as there isnt an option for a tempest x unless you imputed all the info.

Anyone have the file to upload into Win ISD for the Tempest X?

I cant figure anything out in Win ISD, is there a tutorial? I was trying to use the standard tempest but still got nowhere. Am i looking at SPL or whats going on?

**SteveCallas** · **04-12-08, 02:43 PM**

I don't think anything to the effect of "it sucks" was ever mentioned. Limited to 223 liters, an infrasonic tuning essentially results in a FR similar to that of being sealed - you do retain the advanatges of lower distortion and more headroom though.

Inputting driver parameters into WinISD isn't too difficult. Create a new driver and use the data in my attached picture - enter the green and let it calculate the blue.

**Jodean** · **04-12-08, 03:01 PM**

What do i do with the voice coil resistance? Ive got each 8 ohm coil hooked up to one channel of a two channel amp @ 80w each

Ive been playing more with win ISD and something is definetaly wrong. I get a xmax of .01 at 20 hz. And ya im getting the same graph for vented or sealed.....but something is wrong. Im using 160w at 8ohm

I guess even if the program is right....its still wrong.

Since i have not glued the endcaps on yet i can tell you that ported is way louder than sealed....takes about 2 seconds to test that theory.

**charcoal grey** · **04-13-08, 11:45 PM**

Here is the graph I came up with comparing your 223 liter design to the 500 liters Steve is talking about. I was curious since I purchased the Tempest-X 2 weeks ago and I am currently designing my sonotube also. You can see the 500 liter enclosure plays much deeper. When I talked to Kevin at DIY he suggested something around 330 liters or larger.

Also in WinISD, did you notice the input variables can be adjusted when clicking on them? Example, when entering VAS mine defaulted to cu.ft. instead of liters. So if you entered the value from the web site (which is in liters) without changing it to liters, it might read 324 cu.ft. Something like that might be throwing off your data. May sound like a dumb question but I initially had a few problems because of that.

**Jodean** · **04-14-08, 01:22 PM**

thanks, ill look into that.....EDIT: ya i was using 8.25 cu ft but thats what it is

what should the ohms be as i explained above?

What exaclty is the transfer function magnitude and why are we looking at that instead of spl?

How are you creating the 500l? thats one massive sonotube, i was told i can't go any bigger( i guess i agree with the wife the one i made is large enough).......i probrably just should have bought the dayton dvc and saved the $60

I sure wish someone would have said something when i started the thread below that i should have 500L
http://www.hometheatershack.com/foru...questions.html

**Jodean** · **04-14-08, 05:34 PM**

See this is what im telling you guys....theres something wrong with the modeling...

heres my model with data provided by SteveCallas who hasnt responed to any questions.

**Mike P.** · **04-14-08, 06:01 PM**

500 liters is for a LLT which is a specific design goal. For a ported enclosure the manufacturer reccommends 350 liters, I think. You commited yourself to 225 liters by cutting the tube so that it was a certain height. There are pros and cons to every size.

In the above graphs there must be a mistake in the parameters you entered. The top graph shows you have it tuned to 117 hz.

**SteveCallas** · **04-14-08, 06:40 PM**

There is no mistake in the modeling software, only the data it is being fed. Recheck your parameters.

If you can't really change anything about your sub now, there's not much point in modeling it. You mentioned it sounds great, so I wouldn't worry about it, just enjoy.

**Jodean** · **04-14-08, 08:11 PM**

Quote:

SteveCallas wrote:

There is no mistake in the modeling software, only the data it is being fed. Recheck your parameters.

.

ok im getting closer. I had the Vas at 324 ft^3 and changed that to liters....i also noticed i had to create new projects before anything would change on the graph.

Now my only thoughts are the voice coils which i assumed you had wrong.....and i imputed 2 coils parallel. Should i change that to 1? Then on the signal tab do i do 8 ohm or what? Im using two channels of a stereo for power. It is two eight ohm coils right?

**SteveCallas** · **04-16-08, 11:06 PM**

The voice coils don't matter - just copy exactly what I showed you.

**audio newbie** · **04-17-08, 12:37 AM**

You could add polystuff in the sonotube. That should increase the drivers "perceived" box volume to somewhere around 270 liters.

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