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Old 18th October 2012, 03:33 PM   #131
schmeet is offline schmeet  United Kingdom
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Good idea...
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Old 18th October 2012, 03:51 PM   #132
schmeet is offline schmeet  United Kingdom
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Updated so that the dotted red line does not appear if the pipe has an open end.
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Old 20th October 2012, 01:50 PM   #133
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Just wanted to mention this converter I found:

Convert for Windows - joshmadison.com

I have four different calculators, but this little app is easier to use, with less clicking. It remembers the last session, you can hide unused tabs, transpose the conversion, and run multiple copies (I keep one open for area, and another for length). The only flaw is you can't paste values into it.


schmeet, I do hope you bump the "units conversion" thing up your list of priorities.
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Old 21st October 2012, 02:20 AM   #134
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More work for you, schmeet! :0

In the Enclosure window, could you link the "update" button to the "edit" button? Hitting "update" presumes you meant to make the edits, and there's no visible sign the edits were made (aside from the re-hilighting of the element affected). But other than reducing the chance of errors, it would enhance workflow when tweaking dimensions.

Instead of:
tweak number, click Edit, click Update, look at graph, sigh, tweak number, click Edit, click Update, look at graph, sigh, tweak number, click Edit, click Update, look at graph, sigh, tweak number, click Edit, click Update, look at graph, sigh....

we could:
tweak number, click Update, look at graph, tweak number, click Update, look at graph, tweak number, click Update, look at graph, tweak number, click Update, look at graph, smile....

Obviously, the less clicking the better.
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Old 27th October 2012, 10:49 AM   #135
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Hi Schmeet,

a question on v 2.9.4.0, maybe I missed it but I can't find where I can offset the driver.

A good website describing filters and the associated math if you find the time to add that feature (would be very nice to have): Active Filters
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Old 27th October 2012, 02:52 PM   #136
schmeet is offline schmeet  United Kingdom
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Hi Mark.

On the new version you have to offset the driver by having a branch at the start of the line. If you think about it an offset driver is just a branch at the driver to two lines, one open and one closed. This is what you have to model.

So, if you want a 2m line that is offset by 0.3 then you would make the first element a branch with one side 0.6m long and closed, the other 1.4m with an open end.

That make sense?
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Old 27th October 2012, 10:26 PM   #137
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Quote:
Originally Posted by schmeet View Post
On the new version you have to offset the driver by having a branch at the start of the line. If you think about it an offset driver is just a branch at the driver to two lines, one open and one closed. This is what you have to model.
Thinking about this, what's needed is a "taper ratio" input.

That is, you could input either the beginning area or the end area and a taper ratio, and the program would calculate the other value. You'd also want (radio button) check boxes to hold the beginning or end constant as the length was changed.

This would facilitate moving the offset of the speaker in a typical tapered line without restricting the creative freedom of making the two branches different, if you so chose.


Thanks again for your program, schmeet. It's become my main tool, meaning I use it several hours every day.
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Old 28th October 2012, 12:05 AM   #138
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Mark,

The way the program works now makes entering a "typical modern TL" awkward, but the trade off is the ability to model many other enclosure types and things that don't even have names, yet.

Decide on the total length of a line you want to model, the taper ratio, the beginning area, and the offset ratio. Say, 2 meters total length with a 4 to 1 taper, a 1 square meter beginning area and the driver offset a third of the way down the line.


Start the program with the appropriate driver selected, and then in the first element, enter:

The beginning area multiplied by the taper ratio as the 'end area'.
1 * 1 / 4 = .25

The 'end area' multiplied by the inverse of the offset ratio as the 'start area'.
.25 * 3 = .75

The total length, less the total length multiplied by the offset ratio, as 'length'.
2 - (2 * 1 / 3) = 1.33

Click 'Edit'.

Click 'Add Branch'.

Choosing the branch element, use the 'start area' of the first element as the 'start area' of the branch.

Use your beginning area as the 'end area'.

Set the branch 'length' equal to the total length multiplied by the offset ratio.

Click 'Edit'.
Click 'Update'.


There, I think I got it right. Yell at me if it doesn't work.

(BTW, if you look at the GeometryDisplay window, you'll see the branch element shown 90 degrees to the first element. This is odd, but normal. The red lines should make a perfect square cross, indicating that their areas are equal.)
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Old 28th October 2012, 07:58 AM   #139
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Hi Schmeet & Keriwena

Thanks for the help, it all makes sense to me now. as we say in Dutch "het kwartje is gevallen"!

The sim is a double Dayton Audio RSS256HF-4 each powered by it's own amp (Hypex PSC2.400D at max continues power), squeezed into a 65L enclosure..
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Last edited by Mark.Clappers; 28th October 2012 at 08:15 AM.
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Old 28th October 2012, 09:31 AM   #140
schmeet is offline schmeet  United Kingdom
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Hi Mark,

The 'double port' you have there is quite interesting... HOw come you decided upon that?
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