(ooh, right - crappy parking too
Thanks Dave and Bob for chiming in.
As for a meet this year, just no can do.
I had 6 months of bad health and just trying to get some things done,time is what I am very short of for sure.
I had talked to Bob about the new year as I would then have a few things we can show as well for the new year.
I will put the date up in the next few weeks but at this time I will ask Dave and Bob what works the best for them in January 21 or 28 in 2006.
A few months away but you can plan for in in that time frame as well as get some thing ready.
I would like to offer to host as I usually do and will have a few things this year.Yes for space I have a little more room than Bob does
How about a HT8 MTMWW same slim design as the HT3 with more efficency and larger low end presence due to twin Extremis in each.
As well will have the Apex and center channel going as well.
You never know may have a new driver coming next year show up as well
As for a meet this year, just no can do.
I had 6 months of bad health and just trying to get some things done,time is what I am very short of for sure.
I had talked to Bob about the new year as I would then have a few things we can show as well for the new year.
I will put the date up in the next few weeks but at this time I will ask Dave and Bob what works the best for them in January 21 or 28 in 2006.
A few months away but you can plan for in in that time frame as well as get some thing ready.
I would like to offer to host as I usually do and will have a few things this year.Yes for space I have a little more room than Bob does
How about a HT8 MTMWW same slim design as the HT3 with more efficency and larger low end presence due to twin Extremis in each.
As well will have the Apex and center channel going as well.
You never know may have a new driver coming next year show up as well
I think that a meet in late January would ge great, after every's done with some new projects and had recovered from the holidays.
Bob and Dave, is it just me or does it seem like every FR125S user is a local? How are the overseas and overborder sales?
PS: I finished gluing on the back of one cabinet, so I temporarily shoved a driver into it with tack and jammed the leads into a GC. And... wow! This stuff really does live up to its reputation! I was really used to listening to speakers with subs but with this one I don't really miss it at all! I dunno how much of the bass the spials were responsible for, but I temporarily blocked the holes and the bass definately became less deep, but it didn't really become tighter. So I was thinking that maybe the spiral is a nice way to add bass without losing definition. I'll have to A/B with a normal BR box to know though. Geek, youre right, this thing run out of Xmax at 20Hz at around 9W or so.
Thanks Bob for creating such awsome drivers!
Bob and Dave, is it just me or does it seem like every FR125S user is a local?
How are the overseas and overborder sales?PS: I finished gluing on the back of one cabinet, so I temporarily shoved a driver into it with tack and jammed the leads into a GC. And... wow!
This stuff really does live up to its reputation! I was really used to listening to speakers with subs but with this one I don't really miss it at all! I dunno how much of the bass the spials were responsible for, but I temporarily blocked the holes and the bass definately became less deep, but it didn't really become tighter. So I was thinking that maybe the spiral is a nice way to add bass without losing definition. I'll have to A/B with a normal BR box to know though. Geek, youre right, this thing run out of Xmax at 20Hz at around 9W or so.Thanks Bob for creating such awsome drivers!
eVITAERC said:
I agree.
Al, very sorry to hear you have been Ill.... I didn't know. I wish you and your family good health!
eVITAERC said:
Yeah and the best part is it's predictable and if the source impedance is low enough, it's ruler-flat the excursion (See my latest post in my project - with a lower impedance, instead of the "bump", it's straight across to 15Hz or so... )
Because of this predictability, we can easily design around it either mechanically in the cabinet or actively in the preamp (I'm not a fan of XO's in fullranges
)eVITAERC said:
Here, here!
eVITAERC said:
PS: I finished gluing on the back of one cabinet, so I temporarily shoved a driver into it with tack and jammed the leads into a GC. And... wow!
Thanks Bob for creating such awsome drivers!
SWEET! A successful trial! I bought the materials for building a pair just yesterday... I can't wait now! I'm trying out the little 3" driver version, just to really see what these things can do.
Maybe I'll spring for a pair of FR125S if it works out... then ther'll be an international user ;-)
er don't confuse canucks...
..we're international too.
The mathematics discussions, and ideas presented on the web page of Masaaki Takenaka, look an awful lot like the email that I sent him in January. I still think that everyone here and Mr. Takenaka miss the point, slightly.
1) The enclosure/tube system acts as a regular Helmholtz resonator and follows the mathematical behaviour as predicted.
2) the spiral horn really is a spiral horn. If you make the throat size roughly equal to the driver area, and follow some horn mathematics, you can develop that horn independantly. All you have to do is understand that the horn length is really something that looks like the mapping of cartesian co-ordinates to cylinderical
co-ordinates. use mouth are say of 2 and calculate the length required to tune it to Fs of the driver
3) use whatever means that you have to tune a reflex cabinet to the Fs of the driver.
4) fit the horn to the cylinder.
There are a couple of small errors in the mathematics on Mr Takenaka's webpage but proove to be pretty insignificant. Looking back on my notes from January, I can easily follow the process required. perhaps I should copyright the solution....
..we're international too.
The mathematics discussions, and ideas presented on the web page of Masaaki Takenaka, look an awful lot like the email that I sent him in January. I still think that everyone here and Mr. Takenaka miss the point, slightly.
1) The enclosure/tube system acts as a regular Helmholtz resonator and follows the mathematical behaviour as predicted.
2) the spiral horn really is a spiral horn. If you make the throat size roughly equal to the driver area, and follow some horn mathematics, you can develop that horn independantly. All you have to do is understand that the horn length is really something that looks like the mapping of cartesian co-ordinates to cylinderical
co-ordinates. use mouth are say of 2 and calculate the length required to tune it to Fs of the driver
3) use whatever means that you have to tune a reflex cabinet to the Fs of the driver.
4) fit the horn to the cylinder.
There are a couple of small errors in the mathematics on Mr Takenaka's webpage but proove to be pretty insignificant. Looking back on my notes from January, I can easily follow the process required. perhaps I should copyright the solution....
Re: er don't confuse canucks...
Ugh... man I think he patented the idea.
Anyway. The whole thing looks to me like a standard vented enclosure with a horn inserted in the port tube. When i first saw it, my knee-jerk reaction was "spiral-folded transmission line." i did come across some quirky math in the first page, but i thought I just didn't fully understand it. I was a bit thrown by the fact that the tube was a cylinder instead of a cone, but then I noticed the increasing distance between the arms of the helix, so I figured it was just a Log spiral laid out in 3-D space. it is a good space saving idea, and easier to impliment than some quarter-wave round tubing in a "spring" curly shapes that I have seen. Not revolutionary... but a good solid idea.
Nanook said:..we're international too.
The mathematics discussions, and ideas presented on the web page of Masaaki Takenaka, look an awful lot like the email that I sent him in January. I still think that everyone here and Mr. Takenaka miss the point, slightly.
1) The enclosure/tube system acts as a regular Helmholtz resonator and follows the mathematical behaviour as predicted.
2) the spiral horn really is a spiral horn. If you make the throat size roughly equal to the driver area, and follow some horn mathematics, you can develop that horn independantly. All you have to do is understand that the horn length is really something that looks like the mapping of cartesian co-ordinates to cylinderical
co-ordinates. use mouth are say of 2 and calculate the length required to tune it to Fs of the driver
3) use whatever means that you have to tune a reflex cabinet to the Fs of the driver.
4) fit the horn to the cylinder.
There are a couple of small errors in the mathematics on Mr Takenaka's webpage but proove to be pretty insignificant. Looking back on my notes from January, I can easily follow the process required. perhaps I should copyright the solution....
Ugh... man I think he patented the idea.
Anyway. The whole thing looks to me like a standard vented enclosure with a horn inserted in the port tube. When i first saw it, my knee-jerk reaction was "spiral-folded transmission line." i did come across some quirky math in the first page, but i thought I just didn't fully understand it. I was a bit thrown by the fact that the tube was a cylinder instead of a cone, but then I noticed the increasing distance between the arms of the helix, so I figured it was just a Log spiral laid out in 3-D space. it is a good space saving idea, and easier to impliment than some quarter-wave round tubing in a "spring" curly shapes that I have seen. Not revolutionary... but a good solid idea.
OK... somebody check my understanding here. The spiral horn is a logarithmic (equiangular) spiral in 3-D space. A spiral in 3-D is called a helix. The spiral horn is a triangular shape with one Logarithmic sloping side, wound around a cylinder. This makes for a single helix with the distance between arms increasing. Cool so far. Now, I am a little fuzzy on horn theory... what is the exponential in the Log equasion to get the proper slope? Or is it not an exponential, but just a triangular shape with a straight slope? i see no math on the creator's site to explain any of this.
Update:
I haven't finished the speaker yet, let alone do a frequency sweep measurement, but I have strong reasons to believe that there is some stong resonation going on ~2KHz. I've always noticed that a certain note sounded really sharp and piercing, and today I finally sat down with a guitar and determined the note to be C7, which is ~2096Hz.
What's the standard method of dealing with this? Foam? Mats? Spiky sound sponges inside the cabinet?
I haven't finished the speaker yet, let alone do a frequency sweep measurement, but I have strong reasons to believe that there is some stong resonation going on ~2KHz. I've always noticed that a certain note sounded really sharp and piercing, and today I finally sat down with a guitar and determined the note to be C7, which is ~2096Hz.
What's the standard method of dealing with this? Foam? Mats? Spiky sound sponges inside the cabinet?
ug, he patente4d the idea...
but I solved the mathematics completely. I can copyright the solution! He can have the patenrt, but nobody'd be able to use the solution!
The material used for the port need not be PVC pipe, it could be cardboard or fibre glass, whatever. All ports resonate, that's why they "boost" certain frequencies. I'd try dampening the tube with dynamat or similar. Adding mass will drop the amplitude of the resonance.
but I solved the mathematics completely. I can copyright the solution! He can have the patenrt, but nobody'd be able to use the solution!
The material used for the port need not be PVC pipe, it could be cardboard or fibre glass, whatever. All ports resonate, that's why they "boost" certain frequencies. I'd try dampening the tube with dynamat or similar. Adding mass will drop the amplitude of the resonance.
Re: ug, he patente4d the idea...
Copywrite only protects what it looks like and not the theory. Patents protect the application. If you can prove your design existed before the patent, you can invalidate the patent.
Nanook said:but I solved the mathematics completely. I can copyright the solution! He can have the patenrt, but nobody'd be able to use the solution!
The material used for the port need not be PVC pipe, it could be cardboard or fibre glass, whatever. All ports resonate, that's why they "boost" certain frequencies. I'd try dampening the tube with dynamat or similar. Adding mass will drop the amplitude of the resonance.
Copywrite only protects what it looks like and not the theory. Patents protect the application. If you can prove your design existed before the patent, you can invalidate the patent.
eVITAERC said:
Could it be a pipe wall resonant mode? Wrap a blanket and tie it tight around the pipe, if the resonation is reduced significantly, then this could be the cause. In such case the spiral and the pipe need to be glued together very well, and the pipe exterior needs damping, and there are various materials to do this.
Seeking help with the math....
So if I have determined that the best BR port for my project(using Unibox) is 2 vents 24cm in length and a diameter of 10 cm, I use these values in Masaaki's equation?
L=1.5*pi*10cm + 24cm/(1.5+1)
fh=345/2*pi *square root of "S"/Vb*L(as derived above)
How do you figure "S" ?(the cross sectional area of the throat)
Thank You for any help.
I have built a pair of speakers using his helix 125 as a guide. I am sure that I didnt get everything perfect but they sounded so good with a small 4" driver that I really believe in his approach. I am trying to learn more about horns and am thinking of using his design in a PA cabinet. Small size with good lowend output. Hard to beat.
So if I have determined that the best BR port for my project(using Unibox) is 2 vents 24cm in length and a diameter of 10 cm, I use these values in Masaaki's equation?
L=1.5*pi*10cm + 24cm/(1.5+1)
fh=345/2*pi *square root of "S"/Vb*L(as derived above)
How do you figure "S" ?(the cross sectional area of the throat)
Thank You for any help.
I have built a pair of speakers using his helix 125 as a guide. I am sure that I didnt get everything perfect but they sounded so good with a small 4" driver that I really believe in his approach. I am trying to learn more about horns and am thinking of using his design in a PA cabinet. Small size with good lowend output. Hard to beat.
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