Progress?
Any new progress?
I loaded my Lowther DX4 drivers in 3 foot long 60 degree conical horns made from cardboard. I use a large diffuser (par 38 lightbulb) screwed into the Lowther drivers. The makeshift diffusers break up the beaming of the whizzer cone, improving the power response. They sound pretty good and the frequency response is reasonably flat.
These horns load down to 500 hz, although they are leaky so I may be able to get lower with a more permanent horn, a narrower angle, particularly in the vertical dimension.
I bookmarked this posting and associated thread some time ago because of the information contained in it, and the parallel track to what I am doing.
Retsel
Any new progress?
I loaded my Lowther DX4 drivers in 3 foot long 60 degree conical horns made from cardboard. I use a large diffuser (par 38 lightbulb) screwed into the Lowther drivers. The makeshift diffusers break up the beaming of the whizzer cone, improving the power response. They sound pretty good and the frequency response is reasonably flat.
These horns load down to 500 hz, although they are leaky so I may be able to get lower with a more permanent horn, a narrower angle, particularly in the vertical dimension.
I bookmarked this posting and associated thread some time ago because of the information contained in it, and the parallel track to what I am doing.
Retsel
Hello,
I will be updating this thread instead of creating a new one.
Inspired by JBL midrange waveguides I am designing my own waveguides.
Here is a first shot. What I did is that I did a first expansion at 60*30° and a second expansion at 90*45°. Then I plastered and smoothed everything.
I have some boost in the lower frequencies around 400-500hz and I have an accident around 1 khz.
What is good is that I can measure phase shifting around 500hz which might be theoretical.
I would like to design a bigger 60cm wide waveguide. I am not doing it for the gain but to avoid throwing energy to the room.
Should I go with a basic 90*50° square cone and then smoothen a little bit ?
Or try to approximate tractrix ou JMLC ?
Do you have explanation for the 1khz accident ?
Do you think using damping material at the mouth is a good idea ?
I will be updating this thread instead of creating a new one.
Inspired by JBL midrange waveguides I am designing my own waveguides.
Here is a first shot. What I did is that I did a first expansion at 60*30° and a second expansion at 90*45°. Then I plastered and smoothed everything.
I have some boost in the lower frequencies around 400-500hz and I have an accident around 1 khz.
What is good is that I can measure phase shifting around 500hz which might be theoretical.
I would like to design a bigger 60cm wide waveguide. I am not doing it for the gain but to avoid throwing energy to the room.
Should I go with a basic 90*50° square cone and then smoothen a little bit ?
Or try to approximate tractrix ou JMLC ?
Do you have explanation for the 1khz accident ?
Do you think using damping material at the mouth is a good idea ?
Attachments
I have tried regular cone driver but few things fit as perfect as a JBl CMCD in a horn that you describe. My horn is about 55x55x50 cm and that plays down to 210Hz.
Inspired by JBL waveguide
Attachments
More information on your horn ?
To me phase plug helps with higher extension and when compression is used. In my version or version I want there would not be compression
yes i thought it would look like that, smaller entry or phase plug.
https://www.diyaudio.com/community/...ctive-cardioid-ish.350600/page-4#post-6458203
i didnt have that much phase troubles but phase plug balanced directivity. i tried to extentend horn and make entry smaller, sounded really good and got good results but it was too deep size wise
https://www.diyaudio.com/community/...ctive-cardioid-ish.350600/page-4#post-6458203
i didnt have that much phase troubles but phase plug balanced directivity. i tried to extentend horn and make entry smaller, sounded really good and got good results but it was too deep size wise
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Do you mean it is better to have a smaller throat ? My horn throat contrary to JBL is a bit bigger and matches the surface of the driver. Which I thought would be better lol. But phase around 500 is better with mine
A bit like this principle
https://josephcrowe.com/products/sabourin-front-horn-diy-plans
And I smoothed everything!
https://josephcrowe.com/products/sabourin-front-horn-diy-plans
And I smoothed everything!
10cm diameter mouth is good. This somewhat shallow depth horn goes deep in the midrange without being so honky like a really deep horn would be when using a compression driver. I have been successful to push a JA6681B down to 270Hz. Super detailed, but not a relaxed sound. I think I was missing some other details.
Both waveguide seems to play lower after around 1500hz... I have to cheat a little bit when I want to filter at 2khz. 2 khz because then the phase of the STH 100 is wired if crossed lower.
I think I will do a sealed box of 10l to understand what's going on...
I have measured open back and sealed and doesn't change that much ...
However my waveguide and JBL waveguide look a bit the same
I have measured open back and sealed and doesn't change that much ...
However my waveguide and JBL waveguide look a bit the same