horn lengt in hornresp

[crissty]

I have recently downloaded Hornresp, a very good program to simulate Horn Design,(this compliment goes to David J McBean).

Can some Kind Hearted Horn Guru help me how to calculate the length of the horn, for a particular design (i.e. say punisher horn). I want to know how to calculate the different conical sections to enter for the folded horn segments.

Thanks,

Criss.

[AndrewT]

Hi,
the horn is recommended to be longer than a quarter of the wavelength of the lowest frequency to be reproduced.

eg. Hl >= 340/4/F Hl= 340/4/100 = 0.85m = 850mm for a 100Hz horn.

[crissty]

Hi Andrew.
Thanks for the reply,
Please help me how to calculate the length of each folds in the folded horn design, to enter in hornresp.

[Rademakers]

It's not exact science and it's debatable what the exact length should be. Not every person/designer will end up with the same length. Some are more positive to a design then others for different reasons.

Usually just draw the lines that represent the (mid)axis of the horn path in each section. All these lines combined form the total path length. Because of the bends in the horn, the path will be slightly longer than the true axis by little.

Try to find some existing folded horns with known path length and use it as an practice. Other than that use common sense and/or whatever suits you best.

Wkr Johan

[Volenti]

The lengths you use are arbitary, it may help to initially model the horn as a single section exponential to get the response right then re-make the horn in conical sections that resemble the single section exponential. (at least that's how I approached it)

[crissty]

Thanks to all of you, for being so kind to help.

One more thing while learning Back Horn, it asks for the difference in length, what exactly is that difference calculation.

[crissty]

For Back Horn, it asks for the difference in length, what exactly is that difference to be calculated.

[AndrewT]

Hi Crissty,
I am guessing , but could they be asking for the difference in path length from front cone to listening position compared to path length from back of cone through horn to listening position?

[Scottmoose]

Try Martin King's BLH horn worksheet for MathCad (you can download MathCad Explorer 8 from his site if you don't have a full copy, and save plots etc. into something like Word.) Easier to use, and considerably more powerful in my view 9or it will be, once he's included all the updates... ;-)