Yes, I realized that about the calcs...I looked at the spec sheet of the Lab12 and its said a power of 400W, so I used that and the SPL jumped up 5-10 dB. Is that correct?
Also, I will be folding it once. I will post up a model (I haven't gotten to fold it yet) of it stretched out. I am debating on the width of the TH. I was thinking of 50cm wide which gives me a mouth of 48.4 cm. It may require more wood but with the width being only 33.02 cm, the mouth is 73.20 cm long...that is considerable...
***EDIT***
I knew that this TH wasn't constantly tapered. This could pose a problem with driver placement and folding...time to get back to simulating it again...unless there is a shorter way???
Also, I will be folding it once. I will post up a model (I haven't gotten to fold it yet) of it stretched out. I am debating on the width of the TH. I was thinking of 50cm wide which gives me a mouth of 48.4 cm. It may require more wood but with the width being only 33.02 cm, the mouth is 73.20 cm long...that is considerable...
***EDIT***
I knew that this TH wasn't constantly tapered. This could pose a problem with driver placement and folding...time to get back to simulating it again...unless there is a shorter way???
Last edited:
Maybe a bit of a short cut
This is one more way it could work:
Mark
This is one more way it could work:
An externally hosted image should be here but it was not working when we last tested it.
Mark
...
If you already know how much to short then.....
Maybe add it on?
You have to be carefull over a 180 degree fold. Make it a little longer than you think it should be. THat is where most of the short mistakes come into play. If you imagine the horn path going along and measured down the middle of the fold that is the true length. SO around a 180 degree fold you are not really passing to far on the horn length. A general rule of thumb is 1/4 of the actual measured distance is the actual distance when you measure around a fold.
Hope this helps.
Mark
Maybe add it on?
You have to be carefull over a 180 degree fold. Make it a little longer than you think it should be. THat is where most of the short mistakes come into play. If you imagine the horn path going along and measured down the middle of the fold that is the true length. SO around a 180 degree fold you are not really passing to far on the horn length. A general rule of thumb is 1/4 of the actual measured distance is the actual distance when you measure around a fold.
An externally hosted image should be here but it was not working when we last tested it.
Hope this helps.
Mark
Chris
I'm also interested in 20 to 80 or even better 100 Hz. The sims are now looking reasonable.
What drivers did you have in mind?
Sorry for the double post. Wierd glitch in net connection
OK here is the next question.
Where do you plan on positioning your driver?
You did it here in your simulation. 67 cm along from the beginning of the taper.
And your maximum spl is a bit on the optimistic side. Look below.
Mark
OK here is the next question.
Where do you plan on positioning your driver?
You did it here in your simulation. 67 cm along from the beginning of the taper.
And your maximum spl is a bit on the optimistic side. Look below.
Mark
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the driver placement is what i am thinking of. Since i essentially stretched the horn, the S2 and S3 (S2 = S3) have changed, should I place the driver at the new values or the original values. If I put them at the original values, the area will be smaller.
I am going to place this in a corner and if it works, I will build 3 more for each corner...
I am going to place this in a corner and if it works, I will build 3 more for each corner...
Hi,FYI,
First picture: Shows how to fold IME.
Second picture: What to be aware of.
Third picture: An alternative stuffed T-TQWT. The upper FR peak at 90 Hz will in the realty be benign as the box should be stuffed like a TL.
b
Attachments
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