Help designing a Synergy horn please

Abe The Babe wrote:  I'm after geting my hands on a pc, what software would you recommend for this? I've seen a few people mentioning akabak, is it the be all and end all? or should I be looking to use it along with hornresp?

using hornresp you might get an idea of suitable drivers for the mid section but if you want to finish the design you need something like Akabak because the filters are needed to flatten the response of the HF as well as making the mid and high crossover properly. and getting the flare at the mouth right to control the dispersion is quite tricky too. if u get akabak PM me and I will send you the script I've been using.

I intend on doing a good bit of testing with different methods for my own curiosity just to hear and see how big of an effect using different port shapes etc have.

Can I make valuable tests of the mid with just one driver or do I need to go out and get all 4? I'd like to keep cost down on testing if possible, incase the end product is crap or incase I'd be better off using a different driver etc.

Steve_B wrote: Abe The Babe wrote: @ steve, looks interesting. would I be better off testing with mdf or is chip ok? I use chipboard because it is cheaper. If you have deep pockets then you could use a decent ply. The idea is that if you need to change something you are not too worried about the cost. As well as testing the design, building a prototype highlights any practical problems you might encounter in the build.

I think MDF is supposed to be best acoustically. ply of the same thickness is stronger, lighter and doesn't swell up if it gets damp but it has resonances at high frequencies. I'm not sure but chipboard might be unsuitable for HF use because the rough surface might have a damping effect.

http://www.pat2pdf.org/patents/pat6411718.pdf

http://forum.audiopsychosis.com/viewtopic.php?f=3&t=90

"For instance, if you had one compression driver, four midranges in single reflex bandpasses, and four woofers in dual reflex bandpasses, that's basically four resonances. Now stagger those down the horn. So you'd have a tweeter resonance about 1000hz, a midrange resonance around 500hz, a woofer resonance around 250hz, and a SECOND woofer resonance around 125hz."

This bit of information is very important I think; if you want really damn good sounding horn. But yeah that's pretty difficult.


"2.) The cross sectional area where the mids/lows tap into the horn is such that the circumference is equal to or less than one wavelength of the highest frequency you want it to produce. For example, if your mids tap into the horn where the cross sectional area is 93.5 sq cm, then you would not want to have it produce anything above 1KHz."

Edited by hond - 18 February 2013 at 10:50pm