Design: Horn High Sensitivity Speakers

[DrBoar]

If you go to Doctor Boar; DIY loudspeakers and HiFi and scroll down to "Kuben" that is a simplified version of the La Scala. There are two things to notice.

1. Low pass frequency is way higher than predicted by 2Fr/Qes
2. You get more bass close to cutoff if you have a driver with higher Q and lower Fr. No free lunch though, sensitivity goes down and if you have to much of it there will be a peak at cut off.

[Helmuth]

Originally Posted by charly chile

I am very grateful for your advice. It s clear that DIYAudio was the place to look for.
I need to read all the posts more carefully, for a next round of questions. Your feed ack is so great!

1) two drivers is a good idea, means I don't need 2405, I really like that driver and wanted to have it. My question is: with only one horn going up to 18k, is it going to beam too much? When I think in horns, I think in fullness so would be disappointing to find that it only sounds good in a narrow hotspot (like my new fe126 I was testing in open baffle).

Jbl drivers where very innovative and the top 30 years ago and their technique is still modern at this moment, others copied ideas of jbl and are also very nice HF-drivers.
A super tweeter does often not better then 40 degrees of axes. So they are the same as these E-jmlc.

Then I would go for the E-jmlc 600 horn for good dispersion see sonogram. It needs a 1" driver that makes good dispersion. And very good low end for a 1" driver. XO 700Hz 4 order.


Other option is a e-jmlc for 2" driver. very good dispersion also at 10kHz. would be my choice so you can cross low.

2) my woofer eminence omega 18a is good with a 400hz XO, gives big bass, moves lots of air giving a unique feeling. But I think it is very nasty with voices when approaching the mid range. Are all woofers that nasty? Or it is just beacause mine is cheap?
Will a beyma or 18sound perform more nicely in the 500hz zone where I am blending with the horn?

I will write autotech to figure out how much would be shipping for those le cleach/iwata horns.

Best!
Charly

big woofers have often low distortion I do not know about the omega 18a, I think that is a good driver. The efficiency is only more near the 95dB 1Wmeter. You can make a 3Way with the omega18 as a subwoofer. Then you need a midrange 150-500/800Hz.

[Helmuth]

This will make filtering much easier normal second order 3 way. XO 250Hz and 1500Hz. The mid range and seos wave guide will make a very small monitor speaker and a big frontloaded horn sub.

101dB in 2pi down to -3dB 45Hz!



This is great to combine with a dedicated high efficient midrange.
RCF MR10N301 100dB 1Wmtr No horn no coloration

RCF - MR10N301

Now you can cros at 2kHz and use a seos 10 wave guide. With a 1" B&C DE250. Or a selenium one.
Look at the good dispersion. And no horn coloration.

[tinitus]

Originally Posted by Helmuth

This is great to combine with a dedicated high efficient midrange.
RCF MR10N301 100dB 1Wmtr No horn no coloration

I see RCF have added a response curve for horn loading
then its up to the sensitivity of a horn tweeter

and for that, how about a PPSL sub with 4x 18" woofers

[Helmuth]

Design of the box 101dB 45-20000Hz 2pi. I call it " The super la scala ".

Filter idea for sub 1 order low 100Hz
Midrange 1 order high 200Hz and second order low 1000Hz
High second order high 1000Hz

How to hide a mega front horn.
A 1,4 meter high front horn 45cmX55cm. With midrange and seos 10 wave guide. Closed volume omega18 must be reduced to 55 liter.

[Helmuth]

Horn mouth to the front it will help to reach the 1,2 meter horn length easier.




1pi output of the mega sub front horn. with the first order 100hz filter it will make 106dB 1 meter! -3dB 40Hz! 102dB. That is the output box placed near backwall.
With a 5W amplifier this will make a mighty 112dB at 1 meter.

[tinitus]

looks clever Helmuth, but make it twice as big(wider)

[Helmuth]

Omega 18A sub horn placed in the corner ½ pi. With first order low filter 110dB -3dB 37Hz 1 meter. -10dB 30Hz 100dB 1Wmtr Like?
When you build the front horn like I did design, the corner placement is easy.

[Helmuth]

Originally Posted by tinitus

looks clever Helmuth, but make it twice as big(wider)

??

Then it will not meet the simulation.
Horn mouth 2000 square cm = 45X45 cm, it is a smart horn design with low horn coloration and very high efficiency and relative compact. And without a faulty super tweeter.

Who does better? -3dB 37Hz and 110dB 1wmtr.

Even the wood work will be easy witch ads to be a smart design.

[tinitus]

and how/where will you suggest to crossover bass to mid ?