Looking for a horn program to help a friend out?

[Mr Jeff 7]

Hello everyone. I am looking to help a friend out ( because my projects are on hold) with a horn box idea he has and then turn it into a design then a listenable speaker ( If this makes any sense)? I have only built a few O.B's and mostly ported and a few sealed ( but, that's been years ago). He's looking for a back loaded corner horn ( where the mouth of the horn is in the back of the cabinet). So from what I have researched on the ( Internet)? I need a horn program. I also need a program that takes all the angles in the horn box in account? Like this ones at a 90 degree cut and this is at a 60 degree cut. So could anyone help me out? Or teach me what I need to know about getting some results? Am pretty good at math. Cheers Jeff

 

[weltersys]

1)So from what I have researched on the ( Internet)? I need a horn program.
2)I also need a program that takes all the angles in the horn box in account? Like this ones at a 90 degree cut and this is at a 60 degree cut.

Jeff,

1) Hornresp is an excellent, easy to use horn design program.
Akabak is also great, and allows for more horn sections, but is more difficult to learn and make quick comparisons. You can use Hornrep scripts in Akabak and add sections if you feel the need.

There are "hornresp for dummies" threads, as well as the Hornresp thread in the subwoofers section.
http://www.diyaudio.com/forums/subwoofers/119854-hornresp.html
Literally every question possible has already been asked and answered, so be prepared to do some reading/googling to find your answers.

2) Converting the straight horn simulation into a folded horn is tricky, and there are various approaches used, the advanced centerline approach generally is more accurate to the simulation:

Horn Folding - a brief study of the centerline vs advanced centerline method - AVS Forum | Home Theater Discussions And Reviews

Art

 

[Mr Jeff 7]

Thanks Weltersys. This is what I needed. I will start reading tonight. Thanks for you help. Cheers Jeff

 

[j.michael droke]

Average length vers spho's advanced

Jeff,

1) Hornresp is an excellent, easy to use horn design program.
Akabak is also great, and allows for more horn sections, but is more difficult to learn and make quick comparisons. You can use Hornrep scripts in Akabak and add sections if you feel the need. There are "hornresp for dummies" threads, as well as the Hornresp thread in the subwoofers section.
http://www.diyaudio.com/forums/subwoofers/119854-hornresp.html
Literally every question possible has already been asked and answered, so be prepared to do some reading/googling to find your answers.
2) Converting the straight horn simulation into a folded horn is tricky, and there are various approaches used, the advanced centerline approach generally is more accurate to the simulation:Horn Folding - a brief study of the centerline vs advanced centerline method - AVS Forum | Home Theater Discussions And ReviewsArt

Hi there Art: Looking at the posted avsforum reference, the first and second drawings are to easy to make and measure around a corner.... the average is very close to the more complicated "advanced soho method",drawing #5 (in the example drawings the difference is only 0.05cm!) I know I can not cut wood to that tolerance. ...regards, Michael

 

[weltersys]

Hi there Art: Looking at the posted avsforum reference, the first and second drawings are to easy to make and measure around a corner.... the average is very close to the more complicated "advanced soho method",drawing #5 (in the example drawings the difference is only 0.05cm!) I know I can not cut wood to that tolerance. ...regards, Michael

Michael,

Bass horns are certainly tolerant of several millimeters of error in any cut, as long as everything remains air tight.

Simulations assume a straight horn. Once the horn is folded, the corners add to the horn length, (and also may add or subtract to the volume depending on the layout, another issue in simulation accuracy). The "advanced centerline" method of determining the horn path length has been found to most accurately represent the effective path length of a folded horn using non-rounded corners as are typically used in folded horns used for low frequency use. Rounding corners in LF horns "throws away" valuble cabinet real estate, generally reducing output.

Although the centerline lengths in example 1 and 2 average near the same as the "advanced centerline" method, 1 predicts the horn 3.6 CM too long, 2 predicts the horn 3.7 CM too short. With multiple folds, the error is compounded- after only four folds you would cut your horn 14.5 CM too long or short compared to what your simulation indicated. The difference in actual apparent length compared to the simulation will result in a different frequency response than the simulation

Art