Tempest-X 15" on order!

[pappaj]

It is just to help stop the tube from resonating. I don't think you really need to fill it with polyfill, I think most people use polyfill to "add" volume to the enclosure. With the sonosub there is already enough volume. I'm sure there is someone here that has a better answer for you as I am fairly new myself.

What type of design are you going with and what is the sub going to be used for ? I will definetly recommend a sonosub mine still seems to impress me. I also listen to music with it and I think it sounds great for even music.

[jr1414]

I would love to do an LLT solution, but the space is limited, thus the desireability of a sonotube design. I'm considering trying an LLT/tube design and making the sub appear as a column. I've got 14' ceilings, so it will be interesting to see what kind of volume I can accomodate in that space. I'll probably have to so some side firing ports, but I'm really not familiar with modeling.

Anyone have any ideas for an LLT tube approximately 14' high?

[Ricci]

The main problem with a sonotube that tall would be getting it in your house at all, or out of it.

[jr1414]

Not a problem for me. Have a big double door to get it through. My bigger problem would be geting the length of sonotube home on the roof of my truck!!!

[pappaj]

I think the volume in that tube would be too much the tube would have to be about 18" dia.

Maybe you could make the top of the tube a fake and blend it together. This way you could make it in two sections.

You could make a normal sonosub about 6 or 7' high make a top plate with enough space for the port to breath, stack the next piece of tube on top to fill the rest of space then rap the whole thing in fabric covering the port opening. This should work if you use a breathable fabric.

[cixelsid]

jr1414 wrote:

Anyone have any ideas for an LLT tube approximately 14' high?

Yes there are issues when the end of the port is 5' or more away from the driver.

[jr1414]

Still kicking around ideas. Was considering building a sonosub LLT and corner placing it, possibly 5-6' tall (depending on the modeling) having a small gap between (approximately 6.3" from the SonoSub software) and then building a circular SuperChunk style bass trap above and finishing to match the sonosub. This would essentially have the appearance of a floor mounted column and a floating column above, which would double as a bass trap.

I would treat the other corners of the room similarly to maintain some symmetry in the room, configuring each as a circular SuperChunk bass trap. I know this is kind of off topic, but has anyone tried a circular SuperChunk bass trap, corner mounted? I'm curious as to whether this would be a good idea or not.

[brent_s]

cixelsid wrote:

Yes there are issues when the end of the port is 5' or more away from the driver.

Could you elaborate? I'm pretty sure I've read in some text (thought it was Dickason's LDC but can't find it now) that keeping the port within one wavelength was the general recommendation and even that distance was aimed more at main speakers. At 20hz, even the 1/2 wavelenght is 28'.

Kinda makes sense if you think about it this way. Around tuning and about 1/2 octave either side, the port is responsible for a bulk of the output. At normal listening positions and subwoofer tuning frequenices, you can't localize the source of the output, making port to driver distance nearly meaningless.

With the same information, we can see why it does matter to a main speaker. As the tuning frequency gets higher, that octave of port contribution also gets higher in frequency and thus more directional.

-Brent

[jr1414]

I'm interested in the information regarding the port being more than 5' away from the driver too. Seemed kind of arbitrary, but still would be interesting to learn the theory behind it. It definitely won't apply to my current concept, but I'm always ready to learn something new. Thanks.

[Mike P.]

cixelsid wrote:
Yes there are issues when the end of the port is 5' or more away from the driver.

Brent, from what I've read, there is the a possibility of a standing wave forming in the 90-110hz range if the sub is taller then 5 feet. Here's a link. Scroll to the bottom of the page.

http://dustin.bunnyhug.net/sonostart.php

[jr1414]

So what would the preferred method to break up the standing wave be, other than shortening the enclosure? It's easy to point out a problem, but would it require offset baffles, or would just a brace or two be enough to break up the standing wave? Thanks.

[Mike P.]

The solution in the link posted above was to put about a foot of insulation around the port to solve the problem.

[brent_s]

Mike P. wrote:

cixelsid wrote:
Yes there are issues when the end of the port is 5' or more away from the driver.

Brent, from what I've read, there is the a possibility of a standing wave forming in the 90-110hz range if the sub is taller then 5 feet. Here's a link. Scroll to the bottom of the page.

http://dustin.bunnyhug.net/sonostart.php

I was questioning the statement that the port opening needs to be within 5' of the driver.

Port lengths that support a resonant frequency within or near the passband of the subwoofer is a whole different animal. WinISD and Unibox both calculate the first pipe resonance for you for this reason. I think the recommendation is to get the first resonsonance frequency above 200hz...obviously the higher the better.

-Brent

[Mike P.]

I misread cixelsid post. My mistake.

[pappaj]

My sono with endcaps installed is approx 378L, tuned to I think 14hz with a 7.5" tube at I think 29" long. I'm not positive on the tune but that is the tube I used for the port and the sono size is accurate. I think I have tuned this too low for this sub the sub definitely reaches deep but lacks in overall output.

[Mike P.]

Thanks for the update, John. I was wondering what net volume you used. According to the numbers you posted, the tuning would be 16 hz.

[pappaj]

Overall I'm not too impressed with this sub. The smaller sonosub I built using a car 15" (audiobahn) has quite a bit more output well alot more output, I would like to switch the subs and see if I just made the tube too big for a 15" as it is almost in to 18" territory. I should have just got an 18".

Are you planning on buying a Tempest Mike ?

[Mike P.]

pappaj wrote:

Overall I'm not too impressed with this sub. The smaller sonosub I built using a car 15" (audiobahn) has quite a bit more output well alot more output, I would like to switch the subs and see if I just made the tube too big for a 15" as it is almost in to 18" territory. I should have just got an 18".

Are you planning on buying a Tempest Mike ?

I ended up getting a pair of IXL-18's and I also have a pair of Ascendant Audio Atlas 15's. I'm curious why your sub sems to be under performing, especially when others have reported excellent results. What are you powering the sub with?

[WillyD]

I agree with Mike. You really shouldn't be so underwhelmed by this sub. As he asked, what are you powering it with?

[mlstrass]

My first sono was 2 of the original Tempests in 480L tuned to 19Hz, getting 250watts per driver. It absolutely slammed for music and had plenty for HT.

You could raise the tuning to 19Hz or so and gain some output that way or consider getting another "X" and building a new sono. I also don't care for super low tuned subs and maybe that's not for you either.