Acoustic Horn Design – The Easy Way (Ath4)

[mabat]

Just an experiment - 1.4" throat driven by flat wavefront (axisymmetric free-standing waveguide ~ ⌀450 x 150 mm):

a) throat angle = 0 deg

b) throat angle = 50 deg

 

[mabat]

The same for 1" throat:

a) throat angle = 0 deg

b) throat angle = 50 deg

 

[mabat]

1" throat, a bit of rolling back added (waveguide ⌀438 x 150 mm)

 

[limacon]

Tease! 😁

 

[tmuikku]

Holy flatness batman!

 

[mabat]

1.4", ⌀540 x 175 mm, no rollback. Not so nice -

 

[mabat]

1.4", ⌀500 x 175 mm including rollback.

The time of huge enclosures is over

 

[mabat]

Simple circular arc as the waveguide profile, ⌀480 x 220 mm, 1.4", no rollback:

 

[mabat]

Small rollback added, ⌀460 x 220 mm, 1.4"

 

[TNT]

Rock & Roll-back :-D

//

 

[mabat]

Profile of the above one:

Geometry.Definition = 1
Throat.Diameter = 36
Throat.Profile = 3
CircArc.TermAngle = 1
Coverage.Angle = 45
Length = 220
Rollback=1
Rollback.StartAt=0.48
Rollback.Rate=0.008

 

[jzagaja]

Small rollback added, ⌀460 x 220 mm, 1.4"

Resembles Minphase horns

 

[mabat]

I have no clue what it could be compared to - it's simply a rolled-back circular arc. It beams, that's for sure, although very gradually. In the end it isn't any more directional than the other ones in the highest octave, which is interesting. Don't ask me what's better.

 

[mabat]

...

 

[mabat]

Once again, little more.

 

[Drofdissonance]

mbat, saw you indicate that you are looking to be able to make a speaker without the big baffle. how does a freestanding horn let you achieve this though?

since you still need another driver still in some kind of baffle, and its probably still gonna be pretty big, wont it pretty much be a zero sum game?

 

[mabat]

Reducing an enclosure volume to half is not a small deal
I guess this is very much subjective - for me the free standing horn is far less obtrusive. Also, as long as you don't need the (mid)woofer to produce low bass, its box can be pretty small as well - or even an open baffle.

 

[Ro808]

A question:
I tried to run a modified demo11, but got these messages.
Any ideas?

 

[Ro808]

Good to see the experimental profiles mabat!
These are the answers to my questions, so to speak.

To me personally, the horn in post # 3429 is most interesting, but who am I?
The directivity, while not optimal, is still nothing to sneeze at.


I like this already:

 

[jzagaja]

To me personally, the horn in post # 3429 is most interesting, but who am I?

Smooth HF rollof is preferred in a room? One could plot acoustic power vs. Harman's curve.