My TC-2000 Sonosub design thread

[Adam321]

Well, I guess I am all in now. : I aquired a piece of 20" Sonotube. My design will be as follows. I cut the sonotube to 4'9 1/2 inches. I ordered the 6" flared tube kit from ThrillerAudio. Plus an additional 12" tube and connecting ring, for a total of 29" This tunes to about 15.9Hz. in the approximately 260L tube after subtracting for the tube caps and driver. Please feel free to check my calculations!

The questions I have now are what size t-bolts fit the TC-2000 driver? I don't think bigger than #8's will fit the mounting holes. So, 8-32's OK? I guess no one uses the allen head screws that come with the driver? What's the best way to mark where to drill the holes for the driver. I was just going to put the driver in the baffle hole and use a marker or something to mark the mounting holes.

When gluing the sonotube encaps together what is the best way to align the top cap (baffle with the big hole for flush mounting) with the baffles with the smaller basket holes?

One more question (maybe two) for now ops: I want to cut the holes for the 6" flared port ahead of time, so I can glue everything together. Do I just cut all three layers with a 6" diameter hole, or should a recess the top cap for the flare, if so how deep and what diameter? What type of glue do you use for the flare? I didn't see any screw holes in the picture on ThrillerAudio's website.

Thanks!

[Eric S]

I would not do any cutting for the driver until you have it in hand. My first guess for cutting would be to turn the driver upside down and lay it on your endcap. Trace a circle around the circumference of the driver and do the same with the mounting holes. Remove the driver and then cut a hole in the center of your drawings and test fit the driver until it seats properly. I know you are anxious to get under way, but working slowly and carefully reduced dumb mistakes and other such problems.

When working with the endcaps, you might want to glue the two layers together first, and then do the routing afterward. Thomas has a nice description of how to do with on the KloneAudio web page somewhere. (check this link: https://web.archive.org/web/20091106...5Mini-Me1.html) Essentially, you route the wider diameter recess first (not all of the way through) and then reduce the radius on the circle jig and cut the next hole all of the way through.

Hope this gets you started...
Eric

[ThomasW]

As Eric said, the wise builder does no cutting in advance of having the parts in hand. This includes buying driver mounting screws.

Here's how I do endcaps.

https://web.archive.org/web/20070223153753/http://home.comcast.net/~audio-worx/page88Tube-Zilla1.html

Here's how I do flared ports when the plan is to cover them with a grill

https://web.archive.org/web/20070223152839/http://home.comcast.net/~audio-worx/page93PetesTube.html

After determining the port length is correct I glue them in with epoxy

[Adam321]

Thanks for the replies. Thomas, your way of doing the endcaps would have been easier, but I was worried that I wouldn't drill a straight enough hole and my routing from the top and bottom wouldn't align. I don't have a portable drill guide. So, I cut the holes in each piece and now I have to glue them together. It looks like you don't have to recess that port, but I will wait until I receive it before I cut any holes. I would assume that all TC-2000's have the same size screw mounting holes? I have the driver. I just didn't want to bring home both sizes of screws.

I guess the rest of my design looks ok?

[Adam321]

I think I know how I am going to align the driver baffles. I am going to cut a ring out of cardboard to use as an alignment spacer that I can place on the outside of the smaller inside baffle. This will act to center the two baffles together. I will just line up the edges of the cardboard ring and the larger bottom baffle and the inside endcap will be centered in the cardboard ring.

[WillyD]

I guess no one uses the allen head screws that come with the driver?

I use them, and I am not the only one. They have worked very well for me.

[PoorboyMike]

I use them, and I am not the only one. They have worked very well for me.

I used them too.

I like 'em! :T

[Adam321]

I used them too.

I like 'em! :T

Did you guys use a piece of OSB or plywood as the back layer of the baffle to screw into or did you just screw right into the MDF?


Also, where can I buy black car carpeting or headliner material?

[WillyD]

Did you guys use a piece of OSB or plywood as the back layer of the baffle to screw into or did you just screw right into the MDF?

I used 1/2" OSB on the back of the baffle. The srews def dig into it a bit. I also drilled pilot holes into the MDF.

Also, where can I buy black car carpeting or headliner material?

I used black marine carpet which can be found at Home Depot.

[Adam321]

WillyD, thanks, I will look for that carpet at Home Depot. Can I just use spray adhesive to hold it to the tube?

Also, I just received my 6" Precision ports from ThrillerAudio, very fast shipping. They have mounting ring that is 8.5" in diameter and about 1/2" deep. Should I cut the top baffle with a 8.5" hole and then decrease the diameters of the other two layers? I was actually thinking of trying ThomasW's methed and glue the top baffles together first. Then use the router to cut the 8.5" circle as deep as my straight router bit will go and then cut a 6.25" circle from the other side to finish it off.

[WillyD]

Can I just use spray adhesive to hold it to the tube?

I just used some contact cement, the kind in the small metal can and applied it with a foam brush.

And Thomas' method sounds good.

[Adam321]

I have a new question. I found that 10-32 screws do fit through the mounting holes. The problem is my baffle under the woofer is 2" thick. So I need 2 1/2" screws.
I can only find phillips head machine screws that are long enough. I can't find socket head cap screws longer than 2" locally. Can I use the phillips head screws?

[---k---]

Yes, why not. That is what I used. The only downside is that it is mildly easier to strip the head. I think people use the square heads and other screws mainly for looks.

But, if you ask me, when you have an exposed 15" woofer, no one is looking at the screws.

[ThomasW]

Can I use the phillips head screws?

Of course

[Adam321]

My only concern was that the TC-2000 comes with socket head wood screws. The socket head fits perfectly into the rubber gasket that completely wraps the rim of the the subwoofer basket. The phillips heads are a little bigger and will probably pinch the rubber instead of going through it, so maybe I'll use a washer.

[Dennis H]

http://www.mcmaster.com/ has long socket head screws.

[technimac]

My only concern was that the TC-2000 comes with socket head wood screws. The socket head fits perfectly into the rubber gasket that completely wraps the rim of the the subwoofer basket. The phillips heads are a little bigger and will probably pinch the rubber instead of going through it, so maybe I'll use a washer.

What do these look like?
Are they "Allen" hex socket like this..




...square "Robertson" socket (mostly used in Canada, these have excellent torque transmission while resisting cam-out) like this:



or "Torx" (as with Robertson sockets, driver bit cam-out is virtually eliminated) ... BTW, these are stainless steel deck screws:

?

I haven't seen many "socket head cap screws" for wood though.

[---k---]

A lot of us have pulled the rubber surround off and thrown it away. Then to get a good seal, just use some weather stripping from HD or Lowes.

And actually, my last sub I used weather stripping and t-nuts with phillips head bolts. For my current sub, I'm just using weather stripping and drywall screws. Works fine.

You're thinking too much. Just go to your local Ace (they got more bolts and stuff than HD) and find anything that will hold the driver securely in place. You'll be fine.

[Adam321]

Yes, I do have a problem with "thinking to much".

Technimac, they have the allen hex head, but they have a wood thread like the other screws you have pictured. They even came with and allen wrench to fit. They are about 2 inches long.

[Adam321]

Some pics for you

Thanks for everyone's help. I have finished the sub and thought I would post some pics.

I did end up using the 2-1/2" phillips head screws. They worked very well, except that two of my t-nuts didn't hold and I had to remove the driver to repair it.

The big difference between this sub and my old Velo 1215x is the subsonic extension. It makes the sub have much more of a presence.

I did take measurements with REW, I will post them later, they are still on my laptop. I am really not sure what to make of them, so maybe you pros can shed some insight.

[---k---]

Looks great. Actually, it looks a lot slimmer in your room. And a nice glossy black paint. :T

[Adam321]

Looks great. Actually, it looks a lot slimmer in your room. And a nice glossy black paint. :T

Thanks! It does look small in that picture, but the speaker to the right of it is a B&W DM604 and they look tiny compaired to the sub. The room has a 15-1/2 ft. ceiling. I guess thats why everything looks small. Maybe I should have used a full 12' sonotube. :twisted:

[Adam321]

OK, Finally getting around to posting measurements

Here is the measurements I took using REW and my Radioshack analog SPL meter. I corrected the output for the meter.
It sounds great to me, but I guess it could use some equalization.

Also, should I be worried about protecting the woofer from subsonic frequencies that are below my tuning point? If so, what do you recommend for a high pass filter?