I'm a beginner when it comes to TL's and horns. What are some good threads, guides, videos, you recommend that cut straight to the useful facts about these enclosures and designing them with Hornresp, which I have not yet downloaded.
I have seen a few different configurations, and am curious how they generally compare and the pros and cons of each: the driver having a sealed back, a ported back, one side open to the outside of the enclosure, one side exposed near the rear of the inside of the TL, and one side exposed toward the front of the inside TL. It would be interesting to see a phase comparison of the opening of the TL vs the other side of the driver of these different configurations over the usable frequency range and a little beyond, if anyone has done some of those tests.
Also, are there any general rules of thumb regarding the way it is folded to save space: expanding opening (which I assume would increase sensitivity and harmonics), constant size, decreasing area (which I assume would decrease harmonics), smooth bends vs hard right or even acute angle bends? I assume right angle bends would set up harmonic resonances, while acute angles may trap them and prevent their escape while decreasing efficiency.
I realize the potential complexity involved, but I'm trying to just learn the basics.
I have seen a few different configurations, and am curious how they generally compare and the pros and cons of each: the driver having a sealed back, a ported back, one side open to the outside of the enclosure, one side exposed near the rear of the inside of the TL, and one side exposed toward the front of the inside TL. It would be interesting to see a phase comparison of the opening of the TL vs the other side of the driver of these different configurations over the usable frequency range and a little beyond, if anyone has done some of those tests.
Also, are there any general rules of thumb regarding the way it is folded to save space: expanding opening (which I assume would increase sensitivity and harmonics), constant size, decreasing area (which I assume would decrease harmonics), smooth bends vs hard right or even acute angle bends? I assume right angle bends would set up harmonic resonances, while acute angles may trap them and prevent their escape while decreasing efficiency.
I realize the potential complexity involved, but I'm trying to just learn the basics.
http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/opecol.html#c1
I don’t think these low/long 1/4 and half wavelengths care much about the shape of a turn or bend in the middle of the ‘pipe’? Unless you had a whole bunch of switchbacks that ate up dB from forcing things to scatter vibrations back and forth (?)
If you move the driver to 1/3 in the pipe you can prevent an annoying resonace (at the 3 x Fb) but I don’t think folding the pipe 3 x has a measurable affect on that resonace (??)
I don’t think these low/long 1/4 and half wavelengths care much about the shape of a turn or bend in the middle of the ‘pipe’? Unless you had a whole bunch of switchbacks that ate up dB from forcing things to scatter vibrations back and forth (?)
If you move the driver to 1/3 in the pipe you can prevent an annoying resonace (at the 3 x Fb) but I don’t think folding the pipe 3 x has a measurable affect on that resonace (??)
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Beware, if you read 7 articles about QWTL you'll end up with 8 opinions
Starting point
http://quarter-wave.com/
From here you'll find sufficient references to other articles to keep you busy for a while.
Indeed Hornresp is considered the right simulation program for TL design. Others exist in the form of spreadsheets of MathCAD programs.
Starting point
http://quarter-wave.com/
From here you'll find sufficient references to other articles to keep you busy for a while.
Indeed Hornresp is considered the right simulation program for TL design. Others exist in the form of spreadsheets of MathCAD programs.
These descrioptions don’t get your point across. sketches?
Do read King & Augpurger.
A transmisison line is a box that has an aspect ratio such that one dimension is considerably larger than the others (ie a pipe), with a driver mounted somewhere along the pipe and a hole in the box.
dave
One thing I don't understand yet is why the different positions of the back of the driver being exposed to the path of the TL like as seen in these pics with some deep inside, while others are near the mouth.
But I do realize now that in general a TL is any enclosure with a significantly long port or perhaps even sealed dimension.
But I do realize now that in general a TL is any enclosure with a significantly long port or perhaps even sealed dimension.
It's because you posted the wrong examples, as those are all horns.
The long one has a resonator chamber, the fluffy white sound absorber and the slits right at the sides of the throat seems to indicate that.
So you don't have the so-called direct radiation but ...
The long one has a resonator chamber, the fluffy white sound absorber and the slits right at the sides of the throat seems to indicate that.
So you don't have the so-called direct radiation but ...
Ahhh, that's because you posted in the subwoofer sub-foeum!
Indeed that always seems to me very suspicious...I mean why you want to split the audio band and discuss about the first octave(s)??
Ah ah ah
So those are all subwoofers...as you don't hear any mid-treble coming from the mouth of the horn.
TLs don't use a compression chamber..
Or: TLs use a compression chamber that is a LP
Indeed the software...
Clever...
But it mimics the AI approach to the "real world"
Indeed that always seems to me very suspicious...I mean why you want to split the audio band and discuss about the first octave(s)??
Ah ah ah
So those are all subwoofers...as you don't hear any mid-treble coming from the mouth of the horn.
TLs don't use a compression chamber..
Or: TLs use a compression chamber that is a LP
Indeed the software...
Clever...
But it mimics the AI approach to the "real world"