18" Folded Bass Horn Design

[djdan]

Hi ,

I have just finished my design for a folded bass horn powered by a single 18" Selenium Driver ( 18SW1P ).

The horn cabinet is 650 mm High and close cabinets have 125L.

If somebody like this type of cabinets I will apreciate his opinion about this design.

I hope to reach 135dB / 800w rms in 40-100Hz range.

Regards !

[Ruben]

Hi!

I like horns very much! And bass horns are really a challenge, especially for the WAF thing.

With which material are you going to build this? Wood I guess. Then it has to be a very heavy wood to avoid vibrations.

What will be the efficiency of the system with 1W/1M/40Hz?

[djdan]

I think to use 18mm OSB to reduce weight but I will make many reinforcements for walls .
For round walls I will use 6 layers of 3mm plywood glued and pressed togheter in required shape .

I've made some similar horn ( 2 x 15" drivers ) in the past and I saw what potential problem represent weight. So, I've decided to make everything is posible to reduce wight without sacrifice sound quality.

I hope to reach 105 - 106 db/1w/1m at 40Hz .

Bulding a folded horn can be a challenge for every DIY-er but , in my opinion , is the best option for bass range if space isn't a problem.


A funny story about folded horns .

In 1996 I've made for a big club, 4 huge bass folded horn ( 200 x 120 x H100 cm ) powered by 8 pcs. x Eminence ME15-300LF . Amplifiers used was two YAMAHA P4500 ( 2 x 500W ).
For mid-high range I've made two exponential horns powered by 4 pcs. x Eminence ME12-300 and 4pcs. x Eminence PSD2002 1" drivers . Amplifiers used for mid was a single YAMAHA P4500 and for High was a single CARVIN FET450.
All sistem has a 3500W RMS power and the active crossover was set at 150 Hz and 3000 Hz . Sistem was stacked in two ( Left - Right ) vertical array line in the room corners.

Everything was OK and the club owner was very pleased about the sound quality and loudness .

In the same year, in this club was organised a concert with a very popular band . The band sound manager asked what type are bass loudspeakers and when he receive the answere that was custom made , he conditioned the show by hireing a pro sound company.

The pro sound reinforcement company come with 8000W rms for bass and 5000W rms for mid-high range . Loudspeakers used was vented front direct radiating type ( JBL and Dynacord ) and amplifiers used was QSC USA1310 x 10 pcs (6 pcs. for bass and 4 pcs. for mid-high ).

Well , when all equipment was ready for show the club owner noticed to the band manager that all sound equipment sound bad without deep and strong bass and with less loudness compared with the club equipment . After 2 hours of tests and comparations , the decision was to use the club equipment for the show .

[Ruben]

Really cool!

But one thing about bass horns:

What about the phase? I heard bass horns would alter the phase response of a speaker system?

And an other thing, to you, horn specialist :
What do you think about building a front horn for the phl m25 3450, a mdium horn. Say 150-4000 hz?

Nice day to you!

[mikee12345]

Hi!
i have some questions
throat
mouth
rear chamber volume

horn flare type

What about the phase? I heard bass horns would alter the phase response of a speaker system?

horns alter the phase of a speaker the LEAST

sealed boxes arent bad,ported boxes muck it up alot

horns have the best transient response and dynamics and low distortion.

a medium horn. Say 150-4000 hz?

150-4000hz your asking for some magic that only JBL EV and others can supply

too many octaves.150-1.5k perhaps.

if u have specs il model it in hornresp.

[Ruben]

Hello Mike!

Well, the driver is not a compression driver, but an electrodynamic one.

You can find the paramaters here : http://www.phlaudio.com/datasheets/25_pdf/3860.pdf
I'm Sure it would be just fine in a medium horn!

I would like to put it in a cement horn. Heuhhhh... form the moment I have no idea about how to do it, frankly, but I will think about it, and very probably build it.

Thank you very much for answering, and have a good day!

[Brett]

Originally posted by Ruben
Well, the driver is not a compression driver, but an electrodynamic one.

As are all the compression drivers I've ever seen.

You can find the paramaters here : http://www.phlaudio.com/datasheets/25_pdf/3860.pdf
I'm Sure it would be just fine in a medium horn!

Has potential.

[mikee12345]

heres a 3minute go at that speaker
it wont go high

i havent modeled many midrange speakers though,i need ML util to try it also.

[mikee12345]

slightly better.this woofer would need EQ to make it go higher(whether thats a good idea or not,im not sure about)

[ronc]

Your horn appears to be a hyperbolic flare.Do you have any LF distortion from the tight flare rate?
thanks
ron