What are the pros & cons of high-efficiency horns?

[bonzo75]

it will be a different sound though, facing each other as compared to front on. I am sold on dual woofer FLH

 

[christensenleif@msn.com]

so am I

 

[christoph]

it will be a different sound though, facing each other as compared to front on. I am sold on FLH dual woofer FLH

Then you "choose" what final impedance you would like for the two bass chassis and either wire them in series (two 4 ohm Chassis resulting in 8 ohms) or in parallel (two 8 ohm chassis resulting in 4 ohms)

 

[bonzo75]

Two 16 ohms in parallel giving 8 ohms. The two together add 3 db to 100 db woofers and the horn loading another 6 db. I will have 8 ohms of two 16 inchers at 110 db

 

[Audiophile Bill]

so am I

Hi,

What is the cut off and geometry of those horns? You are front loading 2 x 15” woofers in there

 

[christensenleif@msn.com]

Hi,

What is the cut off and geometry of those horns? You are front loading 2 x 15” woofers in there

throat 20x20cm
mouth 70x40cm
horn length 87cm
rear chamber internal measure 40x40x22cm
they´re now "ventilated" to balance pressure in rear chamber with pressure in horn
pre ventilation I had a reflection in the horn@130Hz, which now is at 30
with 2220B 16 ohm from JBL Bonzo is spot on sensitivity about 110db
max excursion of the pair @1watt is 0,3mm so always linear
acoustical rolloff is about 50db/oct from 75.....lopass in this setup is about 550 12db electrical....24 db acoustical
my horns have cavity for sandfilling, but never dared/needed as they´re heavy and dead enough as is...

 

[bonzo75]

The one that i had in mind has bass horn coming in at 500 so not too different from 550

 

[bonzo75]

Leif, you don't like them open at the front?

 

[christensenleif@msn.com]

Leif, you don't like them open at the front?

they re open at the front......the last pic is of the rearchambers with filterbox on top

 

[DaveC]

they re open at the front......the last pic is of the rearchambers with filterbox on top

Looks good!

Have you tried ports vs resistive vents? Or a combination, like a stuffed port? Does the current setup act like an OB with cancellation to the sides?

 

[Audiophile Bill]

they re open at the front......the last pic is of the rearchambers with filterbox on top

Is the sub on the right a tapped horn?

 

[DaveC]

The one that i had in mind has bass horn coming in at 500 so not too different from 550

Sounds good, but consider a mid horn at a lower cutoff won't get too big... I use a ~330 Hz LeCleach horn around .6m diameter with a 4.5" wideband cone driver, which has a high pass acoustic slope starting about 400 Hz.

If you're going for a 2 way or 2-way + super tweeter imo it's best to get as much info from the mid horn as possible, it also allows closer listening distances and less issue with time alignment. At 400 Hz xo I can listen to my horns relatively nearfield, but 400 vs 500 Hz is not much of a difference.

 

[christensenleif@msn.com]

Is the sub on the right a tapped horn?

no it´s a 4 m long 1 fold horn designed by Rune Skramstad with a ventilated rearchamber
bonus with vented rear chambers apart from more even impedance is that it basically acts a a dipol with respect to room, so all bass problems from previous BR bass towers are gone..

 

[morricab]

no it´s a 4 m long 1 fold horn designed by Rune Skramstad with a ventilated rearchamber
bonus with vented rear chambers apart from more even impedance is that it basically acts a a dipol with respect to room, so all bass problems from previous BR bass towers are gone..

How are you dealing with time delay from such long horns?

 

[Audiophile Bill]

How are you dealing with time delay from such long horns?

Was just about to ask - thanks

 

[christensenleif@msn.com]

14msek below 75 Hz is not detectable by human ear...
Rune knows his stuff...

 

[christensenleif@msn.com]

sub horn build details and DIY acticve lopass-filter inc eq boards

 

[Audiophile Bill]

14msek below 75 Hz is not detectable by human ear...
Rune knows his stuff...

Hi Leif,

Would you have a reference for this per chance? Seems to fly in the face of most manufacturer’s of subwoofers recommendations so just curious - not saying it is wrong.

 

[Audiophile Bill]

Hi Brad,

Curious about the fastidious application of driver alignment by the Aries team with respect their subwoofer - I noted the specific citing of the sub very far in front of the drivers. Any further light about this would you know?

 

[Duke LeJeune]

How are you dealing with time delay from such long horns?

If I understand Leif's description if the "ventilated rear chamber" correctly, the front side of the woofer cone has no such long path length. Then the backside of the woofer is what has the long path length.

So far, so good.

But...

If the front of the woofer cone is indeed radiating into the room, then at the frequency where the 4 meter path length is equal to one wavelength - about 86 Hz - the output from the horn emerges 180 degrees out-of-phase with the output from the front of the woofer cone. So depending on the relative loudness of the two, there may be a cancellation dip in that region. If the crossover frequency is somewhat lower than that, any such dip may not matter.

Somebody please correct me if I'm missing something.