How will bracing affect a TL? Is it needed?

[duanebro]

Just wondering how much I can brace a TL. This will just be for a 6" woofer. But after hearing Wolf's RS 125 build. (sorry in never remember the names of speakers.) I am wondering if a very well braced, or deadened TL would help. Or would it just mess up the TL tuning. I can have the box and bracing cnc cut, but I don't want to shoot myself in the foot.

[Sydney]

Re: How will bracing affect a TL? Is it needed?

A bracing system of crossed ( perpendicular ) hardwood dowels is effective and unobtrusive.

[DanP]

Re: How will bracing affect a TL? Is it needed?

That was Wolf's Stance that used the RS125, and hearing that speaker has also made me lust after an extremely dead box. I've heard the RS125 before and it has NEVER sounded better IMO. I think TLs are inherently pretty well braced, but you could also make the walls very thick, which I think was the main factor in the Stance. I don't remember how thick Wolf made the walls, but it looked like at least 1.5" and maybe even 2.25".

Dan

[object16]

Re: How will bracing affect a TL? Is it needed?

You can use 1" hardwood dowel, or if you can find cheap axe handle, the handle is cut oval, which might be better (it looks nicer anyway). Personally, I use axe handle.

[duanebro]

Re: How will bracing affect a TL? Is it needed?

That was Wolf's Stance that used the RS125, and hearing that speaker has also made me lust after an extremely dead box. I've heard the RS125 before and it has NEVER sounded better IMO. I think TLs are inherently pretty well braced, but you could also make the walls very thick, which I think was the main factor in the Stance. I don't remember how thick Wolf made the walls, but it looked like at least 1.5" and maybe even 2.25".

Dan

Ah yes, the Stance. He also added kitty litter to the walls. I guess what I really want to know is can a different type of box have a similar effect if I go through that effort. I kind of think that the amount of pressure generated doesn't matter so much. A dead enclosure will sound better regardless of spl or box type. But will it be as noticeable as it was in the Stance? Or am I wrong?

[billfitzmaurice]

Re: How will bracing affect a TL? Is it needed?

Just wondering how much I can brace a TL. This will just be for a 6" woofer.

Vibration of the cab panels is detrimental, no matter what the alignment. I don't imagine a six would create major problems, though.

[Wolf]

Re: How will bracing affect a TL? Is it needed?

That was Wolf's Stance that used the RS125, and hearing that speaker has also made me lust after an extremely dead box. I've heard the RS125 before and it has NEVER sounded better IMO. I think TLs are inherently pretty well braced, but you could also make the walls very thick, which I think was the main factor in the Stance. I don't remember how thick Wolf made the walls, but it looked like at least 1.5" and maybe even 2.25".

Dan

I will be inclined to agree with you on the how the RS125 sounds. Since this was the only time I've used the RS125-4, and only know of maybe 1 or 2 designs elsewise that used it although as a mid, I don't know how good that rep is, but I like what I got from it.

Also remember that the port was a dual-flared type with a large radius on the exit so there was no turbulence.

The sides are 1.5", the back was 1.25", and the top/bottom/front was 0.75". The sides were thick to facilitate the mass loading internally, and the back/sides/port/top are all tied in with a couple shim-braces and the 1.25" dowel across sides just below the middle.

I do think a thicker-walled TL ould do as you want, just use a core-box in your router and match the patter on both sides of the panel if you want to fill the panels. Don't pre-attach and use elbow grease and a drill like I did. ;)

Thanks for the compliments, fellas!
Wolf

[fastbike1]

Re: How will bracing affect a TL? Is it needed?

Some advice I've gotten is not to change the cross section of the line (i.e. no window brace. Dowels, axe handles, etc would work well since they aren't changing the line significantly.

[Bob Brines]

Re: How will bracing affect a TL? Is it needed?

Some advice I've gotten is not to change the cross section of the line (i.e. no window brace. Dowels, axe handles, etc would work well since they aren't changing the line significantly.

My experience with quarter-wave pipes is that bracing has the same effect as stuffing, as long as the window brace is largely open space. I have used dowels, 4-light window braces and circular window braces. All work about the same. I am currently using 3/4"x2" plywood braces that run the length of the cabinet. I think that this is working better. It makes more of the cabinet wall stiffer than multiple window braces.

One thing to be said for window braces is that they keep the cabinet square, particularly when the bottom is open. (I use the plinth to close my pipes.)

Bob

[Paul K.]

Re: How will bracing affect a TL? Is it needed?

You got bad advice from someone that didn't know what they were talking about. Window braces work just fine as long as you don't get carried away with the size of their cross members and side members to the point that the cross-sectional area is severely restricted.
Paul

Some advice I've gotten is not to change the cross section of the line (i.e. no window brace. Dowels, axe handles, etc would work well since they aren't changing the line significantly.

[fastbike1]

Re: How will bracing affect a TL? Is it needed?

Thanks for the clarification. Not having any experience designing TLs, what's a ball park for severely restricted? 10% loss of section, 25%, ?

You got bad advice from someone that didn't know what they were talking about. Window braces work just fine as long as you don't get carried away with the size of their cross members and side members to the point that the cross-sectional area is severely restricted.
Paul

[Paul K.]

Re: How will bracing affect a TL? Is it needed?

I've never performed that specific calculation, but let's look at an example. Let's say the internal dimensions of the line's area are 9"W x 9"D. If I use a window pane brace where all of of its members are 3/4" wide, the area of the 4 windows will total to 45.6 in2, out of 81 in2, or 56% open (44% restricted, so to speak). I've modeled the effects of such a brace in a TL and they simply aren't visible in the modeling graphs. As the line's cross-sectional area becomes smaller, the widths of the brace's members would need to be reduced, and as the line's area becomes larger, you could, and would probably want to use brace members that are wider.
Paul

Thanks for the clarification. Not having any experience designing TLs, what's a ball park for severely restricted? 10% loss of section, 25%, ?

[fastbike1]

Re: How will bracing affect a TL? Is it needed?

Thanks Paul, that was a great example.

[Paul K.]

Re: How will bracing affect a TL? Is it needed?

You're quite welcome. How much a window pane brace would affect a TL's performance is determined both by how much the line's area is reduced and how thick the brace is. With window braces typically either 3/4" or 1" thick, their negative effects lie somewhere between zero and miniscule.
Paul

Thanks Paul, that was a great example.