What sort of parameters am I looking for for a small rear loaded horn?

[Boscoe]

I know it's to do with MMS and QMS but what are good values to make a compact rear loaded horn and what are the ideal values? Is there any other values that need to be taken into account?

 

[Top Shelf]

Hi Boscoe, are you trying to design a BLH with handwritten formulas ? If so then hornresp is useful for this type of horn but you need to know quite a few more input parameters than those two. Sorry I can't give you the right answer to your question, I gave up trying to design horns by pencil and paper when I learned hornresp.

 

[hooligan72]

I've never been able to get hornresp to download and install properly. I would love to give it a try.

 

[Top Shelf]

Are you PC or mac? If PC press download ,unzip to folder of choice(have you downloaded WinZip extractor yet?), find that folder , and create a shortcut to desktop screen.
Or is it your antivirus program that screws it up?

 

[hm]

Hello Bascoe,
may be my HP would help, to see and imagination,
my reduced formula you can use by a simple calculator:
Calculation of expo horns

If you have AH, AM, l,
k still lacks the flare rate:

ln (AM / AH) / l = k

so you can see the surface
each point out (Al):

INV ln (l * k) * AH = Al

l m, AH + AM + AL in square meters

By Al e.g. m in width and divide
you have the distance in meters

AH = Horn throat
AM = Horn mouth
k = flare rate
l = length


Lengths and flare rate VALUES

K VALUES:
0.37 ~ 10 Hz
0.55 ~ 15 Hz
0.7 ~ 19 Hz
0.9 ~ 25 Hz
1.1 ~ 30 Hz
1.3 ~ 35 Hz
1.48 ~ 40 Hz

About an octave above k plays the horn,
if the length matches. At BL horn lengths
over 3.4 m, you get a suck out
below 100 Hz

4/lamda lengths VALUES
3.4 m ~ 25 Hz
2.8 m ~ 30 Hz
2.4 m ~ 35 Hz
2.1 m ~ 40 Hz
1.7 m ~ 50 Hz
1.4 m ~ 60 Hz

Most of my horns open
the last~ 75 cm (look ALPHORN)
with a double or triple k,
to get a better mouth+room
crossover.