I was busy again on the weekend and added another small TH to my website. I used the Tangband 6,5" again in a 38Hz single folded TH. It will make use of a 4,7mH coil to even out the response.
I'm still waiting for the coils and some spare time to set them up. But once again it was a pleasure to design and build them (we had nice weather here and bbq and some cold beer was available al the time
).
Some more pics and the plans for this TH are on my website as usual.
best wishes.
Erik
An externally hosted image should be here but it was not working when we last tested it.
I'm still waiting for the coils and some spare time to set them up. But once again it was a pleasure to design and build them (we had nice weather here and bbq and some cold beer was available al the time
).Some more pics and the plans for this TH are on my website as usual.
best wishes.
Erik
Hey Volvotreter, these slim towers are really cool looking. Something about the proportions is just right 
I have played a little in google sketchup and came to a folding, which looks kind of like an old backloaded horn or a th115. What do you think about it? Is this folding scheme worth a try? I came to this, since i would like to use the horn up to relatively high frequencies. I had to keep the individual segments rather short, since when an internal dimension is 1/2 wavelength in length, a standing wave occurs.
The driver sits directly at the mouth. In the picture, the membrane would face upwards. The first segment expands only in the width dimension and looks like a V between to plates. It is the same as in the dts20. I use it to get a smooth transition between driver width and horn width.
Hm, i realize that it is really difficult to describe. I hope the picture adds some sense to my words
I have played a little in google sketchup and came to a folding, which looks kind of like an old backloaded horn or a th115. What do you think about it? Is this folding scheme worth a try? I came to this, since i would like to use the horn up to relatively high frequencies. I had to keep the individual segments rather short, since when an internal dimension is 1/2 wavelength in length, a standing wave occurs.
The driver sits directly at the mouth. In the picture, the membrane would face upwards. The first segment expands only in the width dimension and looks like a V between to plates. It is the same as in the dts20. I use it to get a smooth transition between driver width and horn width.
Hm, i realize that it is really difficult to describe. I hope the picture adds some sense to my words
Attachments
MaVo said:Hey Volvotreter, these slim towers are really cool looking. Something about the proportions is just right
I have played a little in google sketchup and came to a folding, which looks kind of like an old backloaded horn or a th115. What do you think about it? Is this folding scheme worth a try? I came to this, since i would like to use the horn up to relatively high frequencies. I had to keep the individual segments rather short, since when an internal dimension is 1/2 wavelength in length, a standing wave occurs.
The driver sits directly at the mouth. In the picture, the membrane would face upwards. The first segment expands only in the width dimension and looks like a V between to plates. It is the same as in the dts20. I use it to get a smooth transition between driver width and horn width.
Hm, i realize that it is really difficult to describe. I hope the picture adds some sense to my words
I really like the way you used the "V" ramps in your throat plates. Yes, it is just like in the DTS20. Your folding looks good to me. If you do not like, or need the tall and skinny box look, then this is how I would fold it too. One piece of advice for you; since your woofer will be so close to the mouth, you will get quite a bit of direct sound off the back of the cone. If you use a pro sound style woofer and not a car subwoofer type, you will get a surprising amount of high frequency off the back of the cone. While this may not be the best HiFi, it may help you cheat with a higher crossover point.
MaVo said:
You want them to be < ~WL/pi of Fh until the bends have enough area for them to pass unimpeded, maintaining the expansion around the bends (i.e. cross sectional area WRT distance from the throat) to minimize reflections back to the throat or develop standing waves between folds.
GM
Hi MaVo,
I think the folding is fine
. Especially the way you did the throat is clever.
One thing I have always tried to avoid is to have a horizontal driver in order to avoid sag of the cone after some time. Since it is hard to say if a driver is prone to sag I tried to bypass this question by keeping the driver vertical.
To do so in your design you could move the mouth to where is bottom of the cabinet is now and turn the entire box by 90°. Alternatively you could design your box that it allows two positions for the mouth by introducing two removable panels. Then you could inforn us if it makes a difference then the mouth is on axis (what you have now) compared to off axis (what I suggested) .
Add a significant amount of bracing. I was surprised to see how much power a 6.5" is capable to apply to the enclosure (even on a tapped horn which is an open duct in contrast to CB). The stiffer the better it is.
Erik
I think the folding is fine
. Especially the way you did the throat is clever. One thing I have always tried to avoid is to have a horizontal driver in order to avoid sag of the cone after some time. Since it is hard to say if a driver is prone to sag I tried to bypass this question by keeping the driver vertical.
To do so in your design you could move the mouth to where is bottom of the cabinet is now and turn the entire box by 90°. Alternatively you could design your box that it allows two positions for the mouth by introducing two removable panels. Then you could inforn us if it makes a difference then the mouth is on axis (what you have now) compared to off axis (what I suggested)
.Add a significant amount of bracing. I was surprised to see how much power a 6.5" is capable to apply to the enclosure (even on a tapped horn which is an open duct in contrast to CB). The stiffer the better it is.
Erik
David McBean said:
Many thanks for the background information, and for the insight into your thought processes. You remind me a lot of another great innovator, the late Paul W. Klipsch. I think it would be fair to say that everyone here is hoping that you will be granted your patent. If nothing else, you have certainly brought tapped horns to the forefront of our collective minds in recent times
Kind regards,
David
I agree that mr. Danley has played a big role in the recent popularization of this kind of enclosure. "Tapped Horn" is a kind of snappy name too
, and I dont mind if he gets an excusive right to use it.Granting complete rights to this kind of enclosure would be highly arguable though. This kind of loudspeaker system is not something new. It has been analysed, reviewed and published in a scientific journal 5 decades ago. It has even been patented before.
I for sure belive that credit should be given when credit is due. And Tom Danley sure earned a lots of em (in my book too!).
But I see no gain for the community (nor the society as a whole) in wrongfully granted patents. With regards,
Jon
ion said:
I agree that mr. Danley has played a big role in the recent popularization of this kind of enclosure. "Tapped Horn" is a kind of snappy name too
Granting complete rights to this kind of enclosure would be highly arguable though. This kind of loudspeaker system is not something new. It has been analysed, reviewed and published in a scientific journal 5 decades ago. It has even been patented before.
I for sure belive that credit should be given when credit is due. And Tom Danley sure earned a lots of em (in my book too!).
With regards,
Jon
For claritys sake perhaps I should add that: I have not examined the patent application in question so I dont really know what mr. Danley is trying to patent. So the above statement should be interpreted as a rather general standpoint regarding patentability.
Cheers!
Hi all, thanks alot for the constructive comments.
GM, i dont know if i understand correctly. I try to repeat it in my words: First, the segments should be smaller than one wavelength / 3.14 of the highest frequency that should be reproduced. Second, i should pay attention to the expansion around the bends, so that there are no steps in the horn. Third, i can ignore the WL/3.14 rule if the horn is big enough to let the waves travel without problem. Do i understand it like you meant it?
JLH, i can use steep crossovers, so this will be no problem, as long as it isnt distortion that comes out of the driver.
Volvotreter, i remember Dan Wiggins of adire audio writing a paper about a similar problem and he had a formula to see how far the membrane will deviate from its normal position. This was pretty basic, just looking at the gravitational force, the membrane weight and the suspension. He came to the conclusion, that with his drivers, the xmax is only made smaller by a percent or so. With pro drivers and their hard suspensions, i think this will be no problem at all. One could also lay the box on the side and the problem is solved. But with "to sag" you probably mean something different - that the suspension loosens up over the time by the constant force which is applied to it. I have indeed not thought about this problem at all. The DSL TH115 has the same driver orientation, so i think it could be ok.
I will try to see what i can do in the final design, your hint about designing the box with two mouth positions is a good idea.
hm, yes, i hope to make it very big I have a big room and figured "why not?" as it gives me free output and also has a psychological factor, which i like. I aim at around 500 liters. I like your blh design, but for woofer purpose, i would skip the last expansion segment (and also the first because of this) and put the driver deeper into the box. This last doubling of the size is so rapid that it wont affect the low frequency response much. But since yours if a fullrange design, i think its good as it is. Our designs are pretty much the same, only that mine is for <200hz and has a bigger mouth size, which brings the need to make it a little bit more complex.
I really need to learn to use google skeptchup better, thats a hard and boring task
GM, i dont know if i understand correctly. I try to repeat it in my words: First, the segments should be smaller than one wavelength / 3.14 of the highest frequency that should be reproduced. Second, i should pay attention to the expansion around the bends, so that there are no steps in the horn. Third, i can ignore the WL/3.14 rule if the horn is big enough to let the waves travel without problem. Do i understand it like you meant it?
JLH, i can use steep crossovers, so this will be no problem, as long as it isnt distortion that comes out of the driver.
Volvotreter, i remember Dan Wiggins of adire audio writing a paper about a similar problem and he had a formula to see how far the membrane will deviate from its normal position. This was pretty basic, just looking at the gravitational force, the membrane weight and the suspension. He came to the conclusion, that with his drivers, the xmax is only made smaller by a percent or so. With pro drivers and their hard suspensions, i think this will be no problem at all. One could also lay the box on the side and the problem is solved. But with "to sag" you probably mean something different - that the suspension loosens up over the time by the constant force which is applied to it. I have indeed not thought about this problem at all. The DSL TH115 has the same driver orientation, so i think it could be ok.
I will try to see what i can do in the final design, your hint about designing the box with two mouth positions is a good idea.
hm, yes, i hope to make it very big
I have a big room and figured "why not?" as it gives me free output and also has a psychological factor, which i like. I aim at around 500 liters. I like your blh design, but for woofer purpose, i would skip the last expansion segment (and also the first because of this) and put the driver deeper into the box. This last doubling of the size is so rapid that it wont affect the low frequency response much. But since yours if a fullrange design, i think its good as it is. Our designs are pretty much the same, only that mine is for <200hz and has a bigger mouth size, which brings the need to make it a little bit more complex.I really need to learn to use google skeptchup better, thats a hard and boring task
Thanks Mavo
no, it is a sub horn for 16 cm driver,
3,06 m long for ~2 oktaves, 30 -100 Hz,
done 2003, 135 L Volume,
new feedback in german.
http://www.hm-moreart.de/59.htm
IMO: For HiFi 200 Hz is to high, at 100 Hz you get mans voice,
if you drive a sub over 100 Hz, the voice gets a large soundstage,
to much? if i see your active radiation area, I think so.
my experience let me say ~at 150 Hz you get a peak ~8 dB.
here a 25 cm alphorn variante
no, it is a sub horn for 16 cm driver,
3,06 m long for ~2 oktaves, 30 -100 Hz,
done 2003, 135 L Volume,
new feedback in german.
http://www.hm-moreart.de/59.htm
IMO: For HiFi 200 Hz is to high, at 100 Hz you get mans voice,
if you drive a sub over 100 Hz, the voice gets a large soundstage,
to much? if i see your active radiation area, I think so.
my experience let me say ~at 150 Hz you get a peak ~8 dB.
here a 25 cm alphorn variante
Attachments
Hi hm, this seems to be an area where tradidional backloaded designs and tapped horns are quite similar. Maybe you could model your alphorn with hornresp in a tapped horn setup. perhaps you can get even more out of it this way
I dont know too much about soundstage and its relation to radiator size, but my mains are horns with 0,5m² radiation area each. If i put them directly on top of the basshorns, i think it will match quite well.
I dont know too much about soundstage and its relation to radiator size, but my mains are horns with 0,5m² radiation area each. If i put them directly on top of the basshorns, i think it will match quite well.
MaVo said:Hi all, thanks alot for the constructive comments.
GM, i dont know if i understand correctly. I try to repeat it in my words: First, the segments should be smaller than one wavelength / 3.14 of the highest frequency that should be reproduced. Second, i should pay attention to the expansion around the bends, so that there are no steps in the horn. Third, i can ignore the WL/3.14 rule if the horn is big enough to let the waves travel without problem. Do i understand it like you meant it?
JLH, i can use steep crossovers, so this will be no problem, as long as it isnt distortion that comes out of the driver.
Volvotreter, i remember Dan Wiggins of adire audio writing a paper about a similar problem and he had a formula to see how far the membrane will deviate from its normal position. This was pretty basic, just looking at the gravitational force, the membrane weight and the suspension. He came to the conclusion, that with his drivers, the xmax is only made smaller by a percent or so. With pro drivers and their hard suspensions, i think this will be no problem at all. One could also lay the box on the side and the problem is solved. But with "to sag" you probably mean something different - that the suspension loosens up over the time by the constant force which is applied to it. I have indeed not thought about this problem at all. The DSL TH115 has the same driver orientation, so i think it could be ok.
I will try to see what i can do in the final design, your hint about designing the box with two mouth positions is a good idea.
hm, yes, i hope to make it very big
I really need to learn to use google skeptchup better, thats a hard and boring task
Yes, if you try to go much above 80Hz with this bass horn, a very steep filter will be needed. The vocal range is most often quoted as being from 80Hz to 1.1KHz. If you can help it, try not to use a bass horn for this range. A deicated mid-bass horn is best suited in the vocal range. You can only cheat so much before you will realize how far you can take it. It is all a personal and subjective thing. You must build it and decide for yourself. Since you are building this for yourself you do not need to please anyone else but yourself.
Mavo i thought you will use one bass,
the traditionell BLH sounds less enclosure sound,
did you see the measurement of the ALPHORN,
i think one is enough for normal room and listener.
http://www.hm-moreart.de/61.htm
the traditionell BLH sounds less enclosure sound,
did you see the measurement of the ALPHORN,
i think one is enough for normal room and listener.
http://www.hm-moreart.de/61.htm
tb46, this is a very educating pdf. i am glad you posted it. if i may ask, were did you get it and does it resemble the real th115?
JLH, i also think this is a tradeoff and i hope it is okay for me - i am not strictly a hifi guy, as i am easily made happy by big horn speakers, which is a thing like man and fast cars. in the worst case, if i build them and dont like the sound over 80hz, i can still make my mains 3way again and keep the subs for sub duty.
hm, i want to build 4 of them. i posted this link to the harman white papers before where they describe how to achieve very uniform low frequency sound with the help of 4 subs, placed over the room. I tried it with closed boxes and it works extremely well, but those lack the spl capabilities i favour.
JLH, i also think this is a tradeoff and i hope it is okay for me - i am not strictly a hifi guy, as i am easily made happy by big horn speakers, which is a thing like man and fast cars. in the worst case, if i build them and dont like the sound over 80hz, i can still make my mains 3way again and keep the subs for sub duty.
hm, i want to build 4 of them. i posted this link to the harman white papers before where they describe how to achieve very uniform low frequency sound with the help of 4 subs, placed over the room. I tried it with closed boxes and it works extremely well, but those lack the spl capabilities i favour.
Posts #1892 / 1895
Hi MaVo: This is just something I drew when I was wondering what the inside of the TH-115 might look like. I just approached it from the outside dimensions. I do like the concept of being able to increase the horn length by raising the height of the box without adding additional 180 degree bends. Glad you find it interesting.
Hi MaVo: This is just something I drew when I was wondering what the inside of the TH-115 might look like. I just approached it from the outside dimensions. I do like the concept of being able to increase the horn length by raising the height of the box without adding additional 180 degree bends. Glad you find it interesting.
im trying to make a very compact folding design for my next project
it needs to be 130db 40-100hz
this may also apply to you as well mavo as your trying different designs
i have seen a few tapped horns without angled expansions, im not sure how impotent this is at low frequency's
ease if construction is a + for this design (no horrid angles, there hard to do in a bedroom)
it needs to be 130db 40-100hz
this may also apply to you as well mavo as your trying different designs
i have seen a few tapped horns without angled expansions, im not sure how impotent this is at low frequency's
ease if construction is a + for this design (no horrid angles, there hard to do in a bedroom)
An externally hosted image should be here but it was not working when we last tested it.
