Spherical Horn / Kugelwellen - Trichter

[Fangio]

... a version of your spreadsheet that opens in MicroSofts' Excel ?

Thanks < Earl <>

xml - opens in MS Excel 98-2008/Mac (including 2001/Mac)
xls - should open in MS Excel 5.0/Mac and later versions.

Enjoy

[Ian Mackenzie]

Ian, it sounds to me like you have it all figured out and might want to talk to Mr. Widget about getting some TAD transducers. Did you get a chance to hear his system when you visited?

I am not suggesting I have anything figured out . If I had a stock K2 and E2 to measure and collect some hard data when I could talk some real fact about those systems.

Beyond that it is really basic engineering principles and working through the compromises you are prepared to accept.

One thing to point out is getting low harmonic distortion and power compression in the Mid midrange is a challenge and there is a requirement for displacement. Hence I would not do smaller than an 8 inch to get sensitivty in the mid early 90's.

No, Mr Widget was moving shop when I was there last but Bo's enthusiasm for that system is inspirational.

Peter,

Have a read of this article. That driver is quite exceptional.

http://www.troelsgravesen.dk/JA8008.htm

[Ian Mackenzie]

Ian,
are you in the phase of discussing basics or is it the search of a good mid bass / mids driver? I am still looking for a candidate, have not found it yet. (Years ago an AUDAX PR170MO predecessor was a candidate which I used - now out of production, but cone brake ups are apparent.)

Then it is a question of making it concrete, fulfilling your design goals. And that is as always a question of compromises (not meaning faults).

Interested to follow your headway.
___________
Peter

PS:
http://www.audioroundtable.com/PiSpe...ges/13339.html
discussing some JBL and 18Sound 6ND410, which is quite nice

Hi Peter,

I have been doing my home work and once you start to have a good look around the constraints or the square you thought you had to work in is not necessarily the case.

What I am looking at is a 2 or 2.5 way system with moderately high sensitivity (92-96 db) that I can run hi end 20 watt class a amps into without the issue of biamping @ 300 hertz and without resorting to the old formula we keep seeing from JBL which are nice but its still the west Coast sound.

I mean I can go and buy better loudspeaker off the floor like a B&W 800 series or a Focal Utopia Be or an Usher Dancer but it will be in the low 90 db senitivity and I will have to resort to 250 watts (which I have). That is not the point of the exercise and I rather not spill $6000 on Feastrex FRD right now looking at the other extreme, Nor am I into into full range drivers that beam like a flash light at high frequencies.(The GPA 604 is supposed to be a vast impovement..perhaps I should hang out for the reviews)

I agree some of the eighteensound drivers are quite nice as are the nitride treated compression drivers. I prefer to use my 2435 be if I can but that depends on finding a suitable horn / wave guide ( not a PA horn).

http://jantzen-audio.com/download/ja..._v2_ja_web.pdf

The same driver presented in this project can use used in a 3 way biamped scenario with a larger 15 inch woofer.

[Earl K]

Thanks Fangio !

- Unfortunately, I can't open 2003 Excel files ( only 2001 & previous to that ) .

- Are you able to do a "Save As" into a 2001 Excel file for Mac or PC ? ( & then repost the attachement ? ) ( Yes, I know I'm quite a beggar )

<. EarlK

[Robh3606]

One interesting point that Earl Geddes and Lynn Olson agree on (they are of opposing view points most of the time) is that large woofers invite large boxes usually and this is recipe for box modes causing colouration and diffraction issues.

Hello Ian


Yes but that's about it. Earl just builds a better box and see's no advantage to going to an Open Baffle approach which for some reason seems to be the rage on that forum. There is some pretty jaded and opinionated stuff in that thread. That whole set-up is going to end up being an OB version of a larger format monitor using classic horns with changing directivity and all the attendant issues that brings. Some good discussions but the bottom line is nothing new there.

Rob

[Fangio]

Thanks Fangio !

- Unfortunately, I can't open 2003 Excel files ( only 2001 & previous to that ) .

- Are you able to do a "Save As" into a 2001 Excel file for Mac or PC ? ( & then repost the attachement ? ) ( Yes, I know I'm quite a beggar )

<. EarlK

Done. One of them should work.

[Hoerninger]

One of them should work.

Proved and tested, ok.

Thank you, Fangio.
____________
Peter

[Earl K]

Thanks Fangio !

- The second file ( .xls ) opened for me .

[audiovoice]

might the best solution be a 38" tractrix horn, with a 8" driver ?


Angelo

[Hoerninger]

Hello Angelo ,

please specify "best solution".
The Tractrix has an inferior sound dispersion compared to a Kugelwellentrichter
__________
Peter

[audiovoice]

hi Peter

as far as i know, the horn flare tractrix x spherical / kugelwellentrichter is almost the same. I am wrong ?

Angelo

[Hoerninger]

Angelo,

unfortunately yes. The tractrix you know. A wealth of information about the Kugelwellentrichter you can find by the links here:
http://www.audiovoice-acoustics.com/...?p=579#post579

(I know German is no problem for you )

On your site you gave a link to the Klipsch forum for the article

"Acoustical Studies of the Tractrix Horn part I and II"
by R.F.Lambert and A.O.Jensen,
The Journal of the Acoustical Society of America
Volume 26, Number 6, November 1954

In the summary of part II there is stated:

The polar response data do show a pronounced columination of the radiated energy along the principal axis of the horn, a result characteristic of horn radiation in general.

Concerning the divergence of the Kugelwellentrichter some data are available.

It would be interesting to have some data of a modern horn which is not too long and which opens wide.
For example the horn of the Everest II.
____________
Peter

[audiovoice]

It would be interesting to have some data of a modern horn which is not too long and which opens wide.
For example the horn of the Everest II.
____________
Peter

hi Peter

the Jean Michel LeCleac'h horn has this characteristic : it is shorter, opens wider, and has a better dispertion . It would be very big , when used in the lower midrange, replacing for example the tractrix horn.

Angelo

[Hoerninger]

Angelo,

it looks interesting.
But the mathematics can only be found in the spreadsheet. There is a language problem, the translator will not handle the spreadsheet.
The measurements do not show the dispersion.
___________
Peter

[audiovoice]

Angelo,

it looks interesting.
But the mathematics can only be found in the spreadsheet. There is a language problem, the translator will not handle the spreadsheet.
The measurements do not show the dispersion.
___________
Peter

hello Peter

according to Klang & Ton 4/91 the Kugelwellenhorn , and Tractrix horn , are identical :

http://www.audiovoice-acoustics.com/...sted=1#post746

see Part 2 of the article series.

Angelo