All my measurements of direct radiating drivers show near field response much soother than far field measurements. I even took the time gradually increase distance from probably 1mm or so and out until I see no significant change in SPL trend. I'd be willing to post my data if you will do the same.gedlee said:
Hello Earl,
Many people having read the topics about waveguides on Diyaudio were convinced that CD could be obtained with a smooth soundfield, they will be disappointed by what you wrote.
We know today that's a large part of horn honkiness is due to a, irregular soundfield emission and then many people think that a smooth soundfield is a goal to avoid horn honkiness. For those persons a smooth soundfield is something more important than constant directivity (which one usually is only obtained above 1kHz minimum).
We could also speak of the benefit for many persons of a reduced diaphragm diplacement inducing less distortion... that another story and I know your opinion on that point.
Best regards from Paris, France
Jean-Michel Le Cléac'h
Many people having read the topics about waveguides on Diyaudio were convinced that CD could be obtained with a smooth soundfield, they will be disappointed by what you wrote.
We know today that's a large part of horn honkiness is due to a, irregular soundfield emission and then many people think that a smooth soundfield is a goal to avoid horn honkiness. For those persons a smooth soundfield is something more important than constant directivity (which one usually is only obtained above 1kHz minimum).
We could also speak of the benefit for many persons of a reduced diaphragm diplacement inducing less distortion... that another story and I know your opinion on that point.
Best regards from Paris, France
Jean-Michel Le Cléac'h
gedlee said:
Jmmlc said:
Jean-Michel - Wrong. CD can be obtained with a smooth sound field, my speakers prove that, nothing that you have shown or that I have said implies otherwise.
"Horn Honkiness" is not caused by "irregular soundfield emission", this sounds like something that you made up to fit your position.
You do not seem to be paying attention. 100% of the people who hear my waveguides agree that the "horn sound" is elliminated and still you claim and claim and claim again things that just do not fit the evidence. You sound desperate to grab onto something to complain about.
Earl,
We have nearly no measurement proving that the soundfield
from your OS waveguide is smooth with the foam plug.
Also here is a quote from you:
"(CD) does not come without its costs. There is a price to be paid to achieve it and that price is a certain level of diffraction and HOM. "
If you agree, well, we shouldn't speak anymore of smoothness of the soundfield, let's speak of the "negative effects of diffraction".
Best regards from Paris, France
Jean-Michel Le Cléac'h
We have nearly no measurement proving that the soundfield
from your OS waveguide is smooth with the foam plug.
Also here is a quote from you:
"(CD) does not come without its costs. There is a price to be paid to achieve it and that price is a certain level of diffraction and HOM. "
If you agree, well, we shouldn't speak anymore of smoothness of the soundfield, let's speak of the "negative effects of diffraction".
Best regards from Paris, France
Jean-Michel Le Cléac'h
Jean Michel
My published measurements show an extremely well controlled sound field. and I have yet to see any polars on your device. Why is that?
Apparently the HOM and diffraction are reduced to the level at which they are no longer audible. That is what everyone agrees to. Why do you continually ignore the unanimous subjective reports? How do you explain those? You supply only your own personal impressions on your side.
My published measurements show an extremely well controlled sound field. and I have yet to see any polars on your device. Why is that?
Apparently the HOM and diffraction are reduced to the level at which they are no longer audible. That is what everyone agrees to. Why do you continually ignore the unanimous subjective reports? How do you explain those? You supply only your own personal impressions on your side.
Earl,gedlee said:
There are many things that are unknown about your data, such as:
1. Is any smoothing done when generating the graphs? To me, it looks like there is. If so, then what what does the data look like without smoothing. Since you use your own software, so the data may not be repeatable using commercially available software.
2. There has never been any indication in your data that actually points to showing how the data would look with significant HOMs and without. Very early in this thread I have pointed this out without anyone addressing the issue. So it is really a very audiophile approach to just say that HOMs are reduced to level at which they are no longer audible. If there is no way of reliably veryfying this using tests, then in commercial practices, one cannot make such claims. At least it would be contested by consumer related organizations here in Taiwan.
It is clear that the Le Cléac'h horn does not have constant directivity, it has been shown. Jean Michel has explained that the Jean Michel horn generates less HOM. So the only way to verify that is to use the same commonly available tools to do measurements, compare the data, and discuss the technical aspects. I'm sure that both of you are not willing to do that.
soongsc said:So the only way to verify that is to use the same commonly available tools to do measurements, compare the data, and discuss the technical aspects. I'm sure that both of you are not willing to do that.
To this I agree. Until we have data on real devices comprehensively measured in the same way (not in the mouth or a single on-axis curve) there is no comparison possible. Nearfield data is not relavent, and I don't necessarily agree with the sims done of the OS waveguide.
It is not I who keeps trying to do these comparisons, I don't see the point - one is CD the other is not - apples and oranges.
waveguide or horn?
Dr. Geddes point seems valid here... after all the thread is "Geddes on waveguides"... not "Jean-Michel on horns"
All I see here is Dr. Geddes discussing his results (subjective and some objective), theories, and observations about why his OS waveguide speaker designs are so well received.
Other posters seem to want to junp on the bandwagon for a ride, simply by stating that their approach is better, w/o much data (subjective or objective) to support this view, whether valid or not.
John L.
Dr. Geddes point seems valid here... after all the thread is "Geddes on waveguides"... not "Jean-Michel on horns"
All I see here is Dr. Geddes discussing his results (subjective and some objective), theories, and observations about why his OS waveguide speaker designs are so well received.
Other posters seem to want to junp on the bandwagon for a ride, simply by stating that their approach is better, w/o much data (subjective or objective) to support this view, whether valid or not.
John L.
soongsc said:
It seems that Bjørn might not be willing to do this.
I would, but it will require much programming before I can import dxf files into my BEM SW. This SW is based on the Fortran code by Stephen Kirkup (See this link and the link I gave in my previous post), but the pre- and post processing routines are written by me, more or less from scratch. So it is quite a lot work...
To import a boundary from dxf or whatever, would require writing the import functions, and some editing functions for setting the boundary conditions, placing field points, re-meshing the boundary etc, and that is not a small job. It is on my to-do list, however, but it will take some time.
Recently I came across a BEM program that could perhaps do what you need, AxiDriver by RDTeam. The demo is free, and you can edit boundaries etc, but not save the files. I have compared the results to my own SW, and the results are identical for identical problems.
Hope this helps
Bjørn
Re: waveguide or horn?
Hello,
So what you want is no discussion but a monolog from Earl?
This is not what a forum is made for. Moderators are fully able to judge whether a reply find its justified place or not in a thread.
About a "design so well received", open your eyes, there is many more Le Cléac'h horns used by audiophiles all over the world than OS waveguides designed by Earl...
Best regards from Paris, France
Jean-Michel Le Cléac'h
Hello,
So what you want is no discussion but a monolog from Earl?
This is not what a forum is made for. Moderators are fully able to judge whether a reply find its justified place or not in a thread.
About a "design so well received", open your eyes, there is many more Le Cléac'h horns used by audiophiles all over the world than OS waveguides designed by Earl...
Best regards from Paris, France
Jean-Michel Le Cléac'h
auplater said:
Re: Re: waveguide or horn?
EDIT: Which is not to say that LC or OS devices sound better than the other, as I have not had a chance to listen to either.
You will have to explain to me what quantity and good reception have in common. All new and useful inventions have had to topple the juggernauts of prior art and tradition, you know.Jmmlc said:
EDIT: Which is not to say that LC or OS devices sound better than the other, as I have not had a chance to listen to either.
Instead of whining that way, it would be much interesting for us :
- Either create a specific thread about your horn in order to avoid polluting the logic of this one. The presence "allowed" by th emoderators does not prevent your message to be out of the main subject of the thread.
- Or perhaps discussing about your Geddes waveguide criticisms you make regularly on your regular french forum, but never directly in the best place for that, i.e. here. I'm prettey sure that Earl would be very interested about the points you disagree about his very own products. I would be very, very interested in reading his answers. I'll won't put here your "arguments" explaining why and where Earl is wrong myself, as they have a "copyright".
In any case, when I read this thread, I expect to read something about Earl's waveguides and possibily debates. Nothing else not directly related to that.
Jipi.
Jipihorn,
Don't you have anything more contributive to this discussion that your ad hominem attacks against me?
I think that many readers of DIYAudio found my publication of the BEM simulations of the OS waveguide performed by Bjørn Kolbrek interesting.
I am no more moderator of the French language forum you spoke about. [son-qc] was 10 years old and at the end of 2008 I transfered the moderation of that forum to the French association Mélaudia. Now, the disussions are stopped on [son-qc] the interface of which was considered obsolete in regards to modern forums and new discussions may arise on the Mélaudia forum (of which I am a simple participant).
If you have been a regular contributor to [son-qc] you should have seen that the criticsms I adress to Earl were rare and more related to the way he communicate than to his ideas.
You have a simplistic unclear vision of the discussion I had or not with Earl and specially about the point you raise : " Earl would be very interested about the points you disagree about his very own products". Most of that has ben discussed yet or is in discussion at the moment for what it seems.
Best regards from Paris,
Jean-Michel Le Cléac'h
Don't you have anything more contributive to this discussion that your ad hominem attacks against me?
I think that many readers of DIYAudio found my publication of the BEM simulations of the OS waveguide performed by Bjørn Kolbrek interesting.
I am no more moderator of the French language forum you spoke about. [son-qc] was 10 years old and at the end of 2008 I transfered the moderation of that forum to the French association Mélaudia. Now, the disussions are stopped on [son-qc] the interface of which was considered obsolete in regards to modern forums and new discussions may arise on the Mélaudia forum (of which I am a simple participant).
If you have been a regular contributor to [son-qc] you should have seen that the criticsms I adress to Earl were rare and more related to the way he communicate than to his ideas.
You have a simplistic unclear vision of the discussion I had or not with Earl and specially about the point you raise : " Earl would be very interested about the points you disagree about his very own products". Most of that has ben discussed yet or is in discussion at the moment for what it seems.
Best regards from Paris,
Jean-Michel Le Cléac'h
jipihorn said:
Seems like something interesting to look into.Kolbrek said:
I would, but it will require much programming before I can import dxf files into my BEM SW. This SW is based on the Fortran code by Stephen Kirkup (See this link and the link I gave in my previous post), but the pre- and post processing routines are written by me, more or less from scratch. So it is quite a lot work...
To import a boundary from dxf or whatever, would require writing the import functions, and some editing functions for setting the boundary conditions, placing field points, re-meshing the boundary etc, and that is not a small job. It is on my to-do list, however, but it will take some time.
Recently I came across a BEM program that could perhaps do what you need, AxiDriver by RDTeam. The demo is free, and you can edit boundaries etc, but not save the files. I have compared the results to my own SW, and the results are identical for identical problems.
Hope this helps
Bjørn