That's a 3 minute sim so it's not a good design but it's a starting point for you. It's a simple 3 segment sim, once you master that I suggest using all 4 segments.
It's about 1/3 smaller than yours, goes a bit louder than yours with the same power input and less cone displacement and it's a lot smoother response. (It is tuned a bit higher than yours though - 20 hz tuning - and shown in .5 pi. I forgot to change that but I don't want to redo the pic.)
Try a horn shape instead of a straight pipe.
EDIT - I also made a couple other mistakes. Change all the CON segments to PAR and change L12 to at least 13 cm so it will actually fit inside the box.
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Also consider that cabin gain will increase the low frequency considerably over the sims.
Using a small ported box with 20 volt input, 40 Hz one meter outdoors, the speaker did 99 dB (C scale, Radio Shack SPL meter).
Inside my shop, it did 100 dBC at one meter.
In my Astro Van, the speaker placed between the front seats on top of a built in storage container, at one meter was 108 dBC. In the drivers seat, 113 dBC.
Cabin gain increased the level at 40 Hz by about 14 dB, the speaker went from quite rolled off LF to a LF boost in the van.
If you design for flat response in Hornresp, you may find the speaker actually has too much LF in the van.
Of course, for some, "too much" LF is not enough ;^).
And always remember to check back against a ported box model. Even the design in post 21 doesn't show any real advantage over a ported box and it's over 3x larger than the ported box. You have to have a TH friendly driver, a good design, and the design needs to be at least 4x larger than a ported box to get significant and worthwhile gains. Otherwise it's usually best to just use a ported box.
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I have measured a 6 dB gain in efficiency with a variety of drivers with TH having the same low corner with an increase in size from as little as 1.25 to 2 times the size of a BR using the same driver.
But as you said, you have to have a TH friendly driver, and a good design 😉.
Ya. That's what I'm talking bout.
I wanted the horn. I'll prob build the horn to hear it and might settle on the ported one anyhow.
I'm really specifying the horn because I want to see the difference. I'm aware that a vented box can do largely the same thing in less space, I guess I'm just feeling horny right now. 😛
I wanted the horn. I'll prob build the horn to hear it and might settle on the ported one anyhow.
I'm really specifying the horn because I want to see the difference. I'm aware that a vented box can do largely the same thing in less space, I guess I'm just feeling horny right now. 😛
Sure, the efficiency gain is usually pretty easy. The problem is that the efficiency gain is offset by the fact that the tapped horn hits xmax with way less voltage than a ported design with the same low corner. I don't compare at one watt (which will highlight efficiency differences), I always compare both designs at xmax (which will show max theoretically spl). I like to see 6 db max spl in a reasonable size before I get too excited about a horn design.
Nothing wrong with that, I encourage you to try a horn. But I'd recommend putting in the time to make sure it's a really good design or you won't really learn much.
Ya guy, that makes sense.
Was noodling with the 3 types of tapped enclosures.
The pipe was saddle shaped
The taper was lower output with extension in a smaller box
The horn had no output below 40 hz but was hugely loud
All reached xmax at 100w inputs, not a problem really because output was acceptable at over 110db in band.
I also dropped the specs into a vented alignment per the drivers datasheet, was comparable to the horns.
Where these tapped lines are concerened, how does one determine a good design from a bad one?
If my requirements are given( eg extension and output into given space) and 2 enclosures hit them how would you discern a good design from a not so good design?
Was noodling with the 3 types of tapped enclosures.
The pipe was saddle shaped
The taper was lower output with extension in a smaller box
The horn had no output below 40 hz but was hugely loud
All reached xmax at 100w inputs, not a problem really because output was acceptable at over 110db in band.
I also dropped the specs into a vented alignment per the drivers datasheet, was comparable to the horns.
Where these tapped lines are concerened, how does one determine a good design from a bad one?
If my requirements are given( eg extension and output into given space) and 2 enclosures hit them how would you discern a good design from a not so good design?
At the very minimum I usually check the schematic (size), spl and displacement graphs (spl at xmax for a given tuning). Usually there's a pretty clear winner by just those 3 metrics, but there's a whole host of other parameters you can check on.
that is tru only for sine wave's,not for music signals.
the th wil have less excursion playing music,because the harmonics are usualy @ a excusion minimum.
Music IS sine waves. A bunch of complex and changing sine waves.
The TH and the ported box displacement graph (for a given tuning and low frequency corner) are very close to the same. Look at the displacement graph in post 18. If the tuning were adjusted so they were both tuned exactly at 20 hz the displacement graphs would overlay very closely with only some subtle differences. Both the TH and ported boxes have excursion minimums in the same places.
Anyway, the harmonics aren't a problem. The excursion problems appear below tuning and in the first excursion bump on the displacement graph located 1/2 octave - 1 octave above tuning. It doesn't matter if you are playing music or sine waves, if you have demanding content at those frequencies it's going to bottom out.
The TH and the ported box displacement graph (for a given tuning and low frequency corner) are very close to the same. Look at the displacement graph in post 18. If the tuning were adjusted so they were both tuned exactly at 20 hz the displacement graphs would overlay very closely with only some subtle differences. Both the TH and ported boxes have excursion minimums in the same places.
Anyway, the harmonics aren't a problem. The excursion problems appear below tuning and in the first excursion bump on the displacement graph located 1/2 octave - 1 octave above tuning. It doesn't matter if you are playing music or sine waves, if you have demanding content at those frequencies it's going to bottom out.
thats what i'm saying
harmics are often louder than fundemental.
below tuning one should use a proper hpf .
look look at the pic below,imagen a low e is played on a basgitar =42 hz+2end harmonic 84hz.
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Louder yes, but they don't require more excursion than the fundamental.
Yes, below tuning there should be a high pass filter.
42 and 84 are not a problem for the ported box. 48 - 60 is the problem area. That's where the real limits are. If the ported system is turned up loud enough to hit xmax at 84 hz, that system is going to encounter a serious problem if a 50 hz note comes along, it will be past xmax.
I see your point - the excursion minimum at higher frequencies is not a bad thing. But I don't agree that it's necessary in any way. It isn't going to allow the system to play louder since the system is xmax limited at a lower frequency. The first excursion bump above tuning is the only one that really matters, that's the system limit.
Hornresp shows the response of a horn changing a great deal at 100w compared to that of a vented or sealed box, could that have a lot to do with the difference in sound character?
What do you mean by "changing"? In Hornresp, the only thing that should change when you change from 1w to 100w or 1000w or 10000w is the graph will rise in spl but the response curve shape will not change. Doesn't matter if it's a sealed box, a ported box, a tapped horn, a flh, a bandpass, etc.
The difference in sound character between a ported box and a tapped horn is due to factors too numerous to mention. They are different alignments. They are closely related but are usually quite different in implementation.
Post a picture of the change you see at 100w compared to 1w in both designs. I'm really not sure what you are talking about.
The difference in sound character between a ported box and a tapped horn is due to factors too numerous to mention. They are different alignments. They are closely related but are usually quite different in implementation.
Post a picture of the change you see at 100w compared to 1w in both designs. I'm really not sure what you are talking about.
Ya now i try it again the distortion is not appearing, perhaps it was an input error.
ok the change happens when i use the max spl tool
*reads hornresp help file* ooooooohhhhhhhhhh!!!!!!!!!
*reads hornresp help file* ooooooohhhhhhhhhh!!!!!!!!!
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If you are going to use the max spl tool you have to understand the info it is providing. I don't have time right now to explain it, but I recommend you don't use it until you find out what it's trying to tell you. Check the Hornresp help file for guidance and if that doesn't help search here in the forum, there's been quite a bit of conversation about the max spl tool.
I never use the max spl tool but it's just a matter of personal preference. I determine my max spl by making sure my displacement graph never goes above xmax (above tuning) and I make sure not to input more power than I think the speaker can handle (Eg). Those are your limits, xmax and voltage.
I never use the max spl tool but it's just a matter of personal preference. I determine my max spl by making sure my displacement graph never goes above xmax (above tuning) and I make sure not to input more power than I think the speaker can handle (Eg). Those are your limits, xmax and voltage.
Hmm. For all its complexity the TH doesn't net me much except perhaps some honks at 30,60,80 hz of about 10db over the min SPL at 40hz.
I modeled a vented design of the same volume and the response is much flatter with a 5db honk at the 20hz tuning, the rest up to 110hz is pancake flat.
Put a 2" x 24" slot port 4-1/2" long in it and its a beauty.
I modeled a vented design of the same volume and the response is much flatter with a 5db honk at the 20hz tuning, the rest up to 110hz is pancake flat.
Put a 2" x 24" slot port 4-1/2" long in it and its a beauty.
Not all drivers work well in tapped horns. You need the right driver and you need a very good design, and a good design will be quite a bit larger than a ported box. I believe this was mentioned several times already.
I'm a bit tired and don't feel like playing right now, but this doesn't sound right at all. What tuning does a 48 square inch port with a length of 4.5 inches give you?
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