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THT Lp

post #1 of 117
Thread Starter 
I am going to start my THT Lp build now. I am wanting to build the TH build but for now I am going to atleast build this horn. Then when I get the rest of the parts for the TH I will build that one.

So for anyone who has done this build I have a few questions.

But the first one is are there 2 different lengths with the sides and panel 2/3?

I think that everything looks like it is going to be 71 1/2" and the 1/2" thickness top will make the total height 72. Is this right or no?

Panel 2/3 both say 72" so I am confused on that. I will be making my THT Lp 24.5" wide.

SO anyone who can help so I can start cutting would be greatly appreciated.

I would have posted all the size cuts I implemented into cutlist but I didn't know if that was any infringement or something I shouldn't do. SO please help if you can

David
post #2 of 117
Sent you a PM, but in case it helps anyone else - 71 1/2" long for the top, bottom and sides. Let er rip!
post #3 of 117
Thread Starter 
Thanks for the help Brad.

Well my build will be the first sub build. And as I have cut a few things before I am trying to get used to this borrowed circular saw. I seem to be off 1/4" short here or 1/4" to much there. SO I will have to try and atleast even the long ones up with the router.

I have cut my first sheet using cutlist. I will probably do the other sheet tomorrow and will have to get one more sheet to finish the build. BUT according to cutlist I should be able to do most of the assembly while waiting for funds.

The cheapest void free plywood I could find cost $104 for a "4x8." sheet.

Oh and another question is what size circle did you have to cut out for your dayton Brad?
post #4 of 117
Quote:
Originally Posted by chrapladm View Post

The cheapest void free plywood I could find cost $104 for a "4x8." sheet.

Oh and another question is what size circle did you have to cut out for your dayton Brad?

Yikes, highway robbery on the plywood prices!

I used 13 7/8", cut with a jigsaw, then cleaned up with a file, then used a 45degree router bit to open up the side toward the speaker surround.
post #5 of 117
Quote:
Originally Posted by chrapladm View Post

I seem to be off 1/4" short here or 1/4" to much there. SO I will have to try and atleast even the long ones up with the router.

are you using a saw guide?
post #6 of 117
Thread Starter 
yes I am using a guide but I think when I first used it somehow the blade didn't cut straight and must have drifted away or something. I now have to guesstimate about 1/8-1/4 inch over from the line and watch the blad as it comes alot closer. I guess if anyone could mess up a easy guide board it would be me.

I will make another guide board after this build. I have already cut everything now so its just a matter of trimming edges and using my glue to help with the mistakes.

They do have some structural plywood at "HD," but it lools like there might be some voids. When I asked the plumber stores for void free plywood the gave me a A/A plywood price of $105. Hell the 3/4 I used for my SLA was $150 and this was the cheapest place I found for void free. They have marine plywood that is void free cheaper but wasn't sure if I could use that wood.
post #7 of 117
Thread Starter 
I have a question on the plans. I have cut everything the best I could and I am now drawing everything on the side panel or whatever it is called. Pnale 4 says it is 15" wide. Is the distance from the very edge closest to the panel 4 to panel 4..... 3 1/2"?

I am confused because when I measure 15" from the other edge to where the panel 4 will end it is definitely closer than 3 1/2". I think I get somewhere around 2 3/4 or something.

SO did I measure wrong or what did I do?
post #8 of 117
Quote:
Originally Posted by chrapladm View Post

Is the distance from the very edge closest to the panel 4 to panel 4..... 3 1/2"?

Looks like a typo - did you mean between panel 4 and panel 3, or between panel 4 and panel 1?

Anyway, the listed panel lengths are "rough lengths, leaving some selvage should you wish to pre-cut them" - i.e. you will need to recut them (and angle the ends on some of them) to fit, when it comes time to put in the next panel. So just mark out the panel locations per the instructions very carefully, check all the distances twice; and when its time to install the panel, measure and cut it to fit according to the outlines you drew on the side panel.

So you probably didn't measure wrong (but do double check), its probably just that you need to trim the panel to fit.
post #9 of 117
Thread Starter 
Its just hard to describe. On the drawings/instructions on page 2 it says panel 4 ends, and panel 6 begins, it reads 3 1/2". I am guessing that this is on the outer most edge of panel 3 to the very end of panel 4?

BUT panel 4 for me ends with less than 3 1/2".

Looking at the drawing you'll see15 1/8" and 3 1/2". !5" panel leaves 3" left over. Then you have a 1/2" added on the panel from the start so now there is 2 1/2". For me to make panel 4.......3 1/2" from the edge I would have to move the top from 15 1/8" away to about 21 1/2". So I hope this clears the question up?!

I am trying to finish drawing in the next hour so I can start gluing the first 3 panels atleast.
post #10 of 117
Thread Starter 
I guess I will just have to make cuts to make the boards fit the measurements given.
post #11 of 117
Thread Starter 
Well I drew everything on the board and will just have to cut the pieces to fit. I have know idea how I am going to make angle cuts but we'll see.
post #12 of 117
Quote:
Originally Posted by chrapladm View Post

Well I drew everything on the board and will just have to cut the pieces to fit. I have know idea how I am going to make angle cuts but we'll see.

Do you have a belt sander? That's what I did for most of the angle cuts - used circular saw at 90 or 45 degrees, then adjusted the angle on a stationary belt sander.
post #13 of 117
Thread Starter 
Thanks Brad. I will be using a belt sander then. I was thinking I was going to have a hard time figuring this out but belt sander is easy enough. I work nights and it is only 2pm on Tuesday here. SO after staying up all day/night yesterday and now day today I sometimes cant think of the simplest things.

I am just very excited on gluing up my first few panels to start.
post #14 of 117
just for fun, shoot a pic or two in along the way. folks like pics. ;-)
post #15 of 117
Thread Starter 
I will. I have been trying to take pics while I can but seem to hardly get any time to do the build. I need to take a few more pics and add them to the computer.

The camera for some reason has not been cooperating lately so I have to have the wifey add photos to her computer then I can use transfer them. So as soon as she gets the chance to upload I will add some pics.

I got Panel 1 , 2 and 3 on. Wasn't the best job but I just did what I could.

I started to glue panel one and could never get it quite straight so I decided to just go ahead with 2/3 panels to help support. Then I only had a few clamps so I just used brad nails and squeezed everything into place.

SO while I was placing everything together I just continued to brad nail everything into place. Then of coarse panel one wasn't straight so I just brad nailed through panels 2/3 to make sure it was straight.

I did all this while being outside and getting eaten alive by mosquitoes It is evening time here and I just wanted to get the main panels on and ignored the mozzies. So I have 3 guide boards holding everything so it is the correct spacing. I have some weights on the guide boards to help push down the panel 2/3 to the side.

SO fingers crossed. I wish this stuff cured like PL pro but it takes longer so I will just have to wait.
post #16 of 117
these are all the experiences that folks would like to see.

if everybody just posts their pics of perfection, everybody else will feel like a f_ckup.

most everybody likes to see the "not so good" pics for two reasons, 1) they won't feel like they have to get everything exactly right for great performance, 2) they won't feel like they are the only person to not get everything exactly right in their build.
post #17 of 117
My THT looked like a mess inside which I posted pictures of. But it still pounds HARD.
post #18 of 117
Thread Starter 
Well I finally was able to upload some pics.

Oh yah I forgot to mention when I was using my circular saw to cut my Sla's I cut alittle to much:


I was told by Brad I would need 13 7/8 hole cut out. So I measured 6 15/16 and used a bolt to hold my router in:



I was off because I measured from the very edge of the outside bolt to the outside of the router bit. And I forgot I was pivoting around the bolt which made my circle about a 1/2" short. So that was a fun episode of freehand routing a circle.

Anyways I got started o gluing the first panel and could never get the panel straight. It even fell over completely when I left for the glue to dry.

I ended up using panels 2/3 to hold panel 1 in place. I also used brad nails(finishing nails). I then only had a few clamps so I just used 3 guide boards to hold the panels 2/3 up and apart at the right distance

I have finally loaded the glued panels back into my shed/garage. and man that thing is heavy and very awkward. Especially with the guide boards hanging out further than the sides.

Here are some more pics of how it is now. I just used some weight s I have to help put some pressure down on the glued panels. We bought this house we live in now in January and the previous owner had these lights in the shed and I never felt like taking them down.







Well, done for now but cant wait to glue some more.

Thats good to hear DL86. Not sure how mine will end up but I am trying to use plenty of poly glue so there is no leeks.

Oh yah and another thing. It says to breakin the driver but honestly I dont have anything that will play 10-15hz. for 30 mins or whatever it is needed.

And I also cant remember how to use my multimeter and see what amount of voltage is going to my sub. I had measured it in volts when I was wondering what my speakers were getting but never got a reading.

SO obviously I wasn't doing the testing correctly or something. BUT eventually I would like to use REW software and do other testings so I can gather readings to compare. And when I grow up I can be just like Lilmike.
post #19 of 117
Quote:
Originally Posted by chrapladm View Post

I have finally loaded the glued panels back into my shed/garage. and man that thing is heavy and very awkward.

Yeah, wait until its done! Still trying to figure out how to get it from the garage and into the HT without scratching it all up - towels and hand truck I guess, and set it on a couple rolled up towels for testing (don't want to bother putting it behind the screen wall yet, since the room isn't done, I'll just have to move it back out after testing).

Quote:
Originally Posted by chrapladm View Post

Oh yah and another thing. It says to breakin the driver but honestly I dont have anything that will play 10-15hz. for 30 mins or whatever it is needed.

I didn't break my driver in either, it will have to break in on its own in the cabinet. I downloaded a few test tones, but some of them seem pretty iffy - the real traps ones give me a lot of pops and crackles, maybe because I'm sending them out of my iPhone?? Hoping my monoprice cables show up tonight so I can hook up the amp, eq, and sub, and at least test for leaks.

Quote:
Originally Posted by chrapladm View Post

And I also cant remember how to use my multimeter and see what amount of voltage is going to my sub. I had measured it in volts when I was wondering what my speakers were getting but never got a reading.

Volts DC should be it - just need to fiddle with the range setting.
post #20 of 117
chrapladm,

You may want to double check the plans. The top edge of panel 1 should be flush with panels 2 & 3 (as should all of the vertical panels). The top of your panel 1 is shorter for same reason. Don't know if you have already cut the remaining vertical panels, but they either need to match the height of panel 1 so that the final side panel lays inside of panels 2 and 3, or you'll need to plug the gap at the top of panel 1 somehow.

-Darrell
post #21 of 117
I think you should be looking for volts AC when you use your multimeter since the signals are a sine wave like AC.

The downside to not breaking in a driver for a cab like this is that it will take much longer since if you run it at the volts recommended you might not want to be in the room for very long.
post #22 of 117
Thread Starter 
Quote:
Originally Posted by darrellh44 View Post

chrapladm,

You may want to double check the plans. The top edge of panel 1 should be flush with panels 2 & 3 (as should all of the vertical panels). The top of your panel 1 is shorter for same reason. Don't know if you have already cut the remaining vertical panels, but they either need to match the height of panel 1 so that the final side panel lays inside of panels 2 and 3, or you'll need to plug the gap at the top of panel 1 somehow.

-Darrell

There is a gap because of my 1/4 here or there off cuts with the circular saw. Most of the other pieces are all pretty close to 23.5". The worst off cut was panel 1. I was going to try and buy some more wood to try again but cant afford it. SO I was going to try and split the difference between the bottom and top to get rid of the gap but forgot to do so while getting eaten.

I have almost a 1/4" gap on the top. Probably a little less. I could wait till everything is placed in and when the last panel goes on I would just seal the gap with the poly glue and brads. Or I do have some scrap sections of plywood that I cutoff the baffle to make it fit in the "drawing." It might be 1/4" I will have to have a look.
post #23 of 117
I like the shop lighting.
post #24 of 117
Quote:
Originally Posted by chrapladm View Post

Well I finally was able to upload some pics.

Oh yah and another thing. It says to breakin the driver but honestly I dont have anything that will play 10-15hz. for 30 mins or whatever it is needed.

I haven't used it in a while, but if I remember correctly, REW will play test tones of any frequency. You should be able to use that to break it in...
post #25 of 117
Thread Starter 
I think I have Horn resp or Winisd downloaded that I think has a tone generator. Not sure which but I will see. I also dont know how I can hook up my computer to my receiver other than headphone to rca's.

I have an interface but it only has firewire to connect to the computer. My computer I am using now only has USB. My old mac is what I used to have everything connected to but that needs a new power supply.
post #26 of 117
Thread Starter 
Well once again I am stuck.

What height is the panel brace for 1/4?

Basically from the bottom of a uncut piece of wood to the top of the triangle what is the height?

I am hoping I can install panels 4, 5, 6 and 7 soon. I will have to call it a night after that.......maybe.
post #27 of 117
2 1/2" (I had to explode the SketchUp plan to measure that one too) - and the edge according to SketchUp is 1 1/16", not 1 1/8".
post #28 of 117
Quote:
Originally Posted by Brad Horstkotte View Post

and the edge according to SketchUp is 1 1/16", not 1 1/8".

Only if your 1/2" plywood is 1/2" thick, rather than the 15/32" that most measures. And that's why the plans specify Measure and then cut them to finished length as you install them to be sure of the final size required
post #29 of 117
Thread Starter 
Are the braces for panel 3/6, or whatever it is, very critical in regards to their length?

In other words if mine are 25-26" long would that be a problem?
post #30 of 117
No I don't think the length of the braces is at all critical as long as they're in the ballpark - they don't define the shape of the horn like the panels do, they just reinforce and stiffen the assembly.
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