Design: Horn High Sensitivity Speakers

[charly chile]

Hi Guys,

A year ago I built an OB based on Saba Green Cones drivers, arround 94db, wonderful speaker, has a size and presence that modern comercial speakers totally lack. I just got tired of them because it's not enough, they don't have enough detail, clearly distort.

So I am ready for a new project.
Collecting all my horn listening experiences: Avant gardes uno and duo, JBL Everest, Altec 19, Fostexs BLH, Lowther BLH, and.

I strongly believe Front loaded horns is the way to go, Because of the details, huge dynamics, great dispersion, high sensitivity, and hopefully great soundstage, but that should depend on the whole system.

I have no experience building horns. but I would like to get better sound on the first try.

Would you be able to help me with the design?

Many thanks.

 

[charly chile]

Please note:
My DAC is a Buffalo III with Legato I/V.
The amplifier, a 71a/45/2a3 compatible SET amplifier (0.7 / 1.5 / 5 Watts respectively).
Please note, this is only one low power amplifier that can use different valves. I am not thinking in triamplification here.
The amplifier is a fine one with Tango transformers, but such a low power. I am thinking I should need 100db speakers at least.

 

[charly chile]

At the moment, I have been trying to read as much as possible, based on that, I am thinking in a supertweeter (JBL 2405), a Mid Horn with some kind of Iwata configuration.
and a Woofer of arround 15 Inches in some kind of box (perhaps reflex, or Onken, don't know).


The challenge seems to be Mid/bass integration, getting a Mid horn going as low as possible.
I am thinking about building my own iwata horn for the mids.
Also, getting a woofer with high sensitivity that can go up and sound nice when doing it.

 

[charly chile]

So seems like it has a lot to do with Driver selection.

I have been researching and seems like brands as JBL, Altec, and TAD are out of my budget. So I am thinking to use new drivers. But with my total lack of experience don't know where to go.

Thinking in a JBL 2405 as Supertweeter
For the mids, no idea, it has to go as much lower as possible. Was guessing 1 inch would be better than 2 inches. And looking at brands like BMS.
For the woofer, I have an Eminence Omega 18A available from my OBs, but dont know if that is the right driver. Seems like it doesnt sound very good higher than 200hz with first order crossovers.

So I have a general idea, but not enough knowledge and experience.
But I promess to build something nice if you can help me in the design.

Cheers,
Carlos

 

[charly chile]

No replies?
Maybe my question was not specific enough?

Ok, what if I create a system? Maybe you can tell if it s going to work or make suggestions for change and Improvement?

Ok, here I go:

1. Super tweeter: JBL 2405
2. Mid: bms 4591
3. Bass: Eminence, omega pro 18 (only because already available) in some kind of enclosure.

I imagine having first order crossover points around 400hz and 6khz.
I would like to haveat least 100db
I would like to go down at least to 40hz

Is obvious to me the 97db woofer is an issue! May be go active for the bass?
Is the 2405 and iwata 4591 plus bin bass a good starting point?
I have heard 1 inch CDs are preferable.
Also wondering if a better woofer, like a new pro JBL could improve things.

Help for this enthusiastic ignorant is very needed.
Thanks.

 

[Joppepoppo]

I would recommend using the 2405 from 9-10kHz and up.
Regarding choosing 1" or 2": If you are to use a super tweeter like the 2405 go for the 2". They will reproduce lower midrange more easy than a smaller diaphragmed driver and will have no problem reaching 9-10kHz.
As always, networks are the most important to get a listenable result. It could be wise to look at an existing design like JBL 4333.

 

[Pano]

The subject is so vast, it's hard to reply. What systems like this have you seen and heard?
How big can you go? What is your budget?
I run a modified Altec A5 VOTT with 416-8A woofers, Altec 288 compression drivers on 1005 horns and Fane super tweeters (JBL clones). My on custom crossovers. I'm very happy with it.

I have not used the BMS driver, but I'd say it's a good starting point, sure. The Iwata horn is superb. I prefer 1/4" compression drivers to mate with a 15 or 18" woofer, but you can certainly make a 1" work. If you build you horn for a 1.4" driver with an adapter for 1", then you could try different things later.

I do NOT think 1st order is the way to go. You can do it, but it's not likely to sound good. And I do think yo should go active SS on the woofer. It will just be easier to get what you like.

Do you have good ways to measure the drivers and speakers? You'll need it. Also some software to calculate with. Most of the software is free.

 

[charly chile]

Thanks for your answers gents!
I am all ears.

I am committed to have better speakers for my new SET, so I will try to be more specific, so at the end we can have a specification.

My. Current speakers occupies a volume of 150cm x 50cm x 50cm
So my plan is a size like that. Otherwise I will have WAF issues with my already permissive wife.

My budget, don't know, I guess 1500usd for drivers. And I will build enclosures and guides.
I think I will be able to build the iwata with a guide and a router over glued layers of mdf or wood or similar. Then bending and glueing layers for the sides.

I accept your suggestion of running bass SS, not because I like it, but because I cannot think a better option to do it with a SET of two watts.

For measurements I have a calibrated berihnger mic with a phantom power soundcard. I have been playing with Holm Impulse software.

I have my Buffalo DAC with legato IV, it will go balanced to a pair of tamura transformers and then to the SET 45 amplifier.
I also have a Minidsp, but I think think minidsp is ok but is not audiophile quality, and DAC is so important to use something cheap.

I have listened to Everest 55000, few models of Avant Gardes and Altecs 19. So I think horns is what I need to get that incredible slam, detail, dinamics and directivity.

Questions:
Why you recommend 9-10k instead of 6khz for XO point?

Can I keep over 100db sensitivity with higher order crossovers?

Know woofers that will be good in the mid bass region up to 1khz?
Just don't know which woofers can move air (15 inches) but can blend gracefully with the horn.

Why do you prefer 1 1/4inch CDs for integration with 15inch woofers?

Cheers

 

[charly chile]

I look quickly at the 4333 speaker, seems expensive
In chile would be even more after shipping.
I am concerned it only has 94db, wondering if that would be enough for a 45.

 

[Helmuth]

I would not make a 3 way because it only will cause interference because the CTC spacing is to big.

Just make a 2 way and look at the HF driver to have good flat response up to 18kHz.

example.
Horn. $185,-
AutoTech JMLC-400 - Horns DIY Sound Group
Horns

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1,4"horndriver RCF cost over here $350,-http://www.rcf.it/en_US/c/document_library/get_file?p_l_id=251814&folderId=22488&name=DLFE-2235.pdf

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Woofer 18sound 15" cost $230,-
15mb606

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Beyma 15lw30

[/QUOTE]

This would make a 100dB 1Wmeter 2way system possible 35Hz-20kHz -6dB. Drivers and horn $763,- for one loudspeaker. And 3way will only increase cost and give less pin point sound stage.

Here my own horn system 94dB 1wmtr 30Hz-20kHz very precise pin point stage accurate inpulse behaiviour. Nice clear HF without super tweeter, in fackt I never had better sparkling HF I am using a 2" titanium diaphragm HFdriver. But I think now a 1,4" driver has best of two worlds over the band with. You will have the desired point source wave front when you make it 2 way.
http://www.diyaudio.com/forums/multi-way/204444-photoshoot-ob-mk1-least-they-sound-good.html

 

[Helmuth]

some low cost HF drivers.


BMS 4554 1,4" $202,-
Faital PRO HF144 1,4" $298,-
Eighteensound HD1480T $312,-

Faital PRO HF204 2" $307,-
Eighteensound HD2080T $335,-

Selenium D3305Ti DPD $159,-
http://www.jblselenium.com/marcas/produto.php?id=114&idLinha=40

B&C DE610-8 1.4 $200,-

Radian 745PB 1,4" this looks very decent for the money $235.-
http://radianaudio.com//components/com_virtuemart/shop_image/prod_files/636pb_745pb_835pb.pdf

 

[tinitus]

would like to try this one


FaitalPRO | HF Drivers | HF107

 

[Helmuth]

I think selenium is easy available in chile.

the 15WS600 good bas extension -6dB 28Hz 96-97dB 1W. $185,- bottom price imo.

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Selenium 15WS600 15" 600W Woofer 264-393

 

[Helmuth]

would like to try this one


FaitalPRO | HF Drivers | HF107

A 1" driver will reduce the cost a lot, only problem poor mid response there are nice ones that do 800Hz.
Like the popular 1" DE250 $128,-
http://www.parts-express.com/pe/showdetl.cfm?partnumber=294-605

Here a nice horn for 1" $200,-
AutoTech Iwata-600 - Horns DIY Sound Group

Will look good with 15" woofer about the same with.

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Then one speaker would cost $513,- drivers and a horn for 2 way.

 

[Helmuth]

I think that the 2" fatialpro offers very good low response usable down to 500Hz with a 24dB filter. For hifi low power amp input a second order filter will also do. Will make a great precise midrange response.
Faital Pro HF204 - Faital Pro HF204 2" neodymium high frequency compression driver with a ketone polymer diaphragm. Faital Pro HF204 HF drivers available here at US Speaker.

This to gather with the 15WS600 woofer a 97dB system 28Hz-20000Hz XO 500Hz. And the state of the art JMLC 2" horn. Point source 500-20000Hz
For $605,- 2"driver fatialpro, jmlc400, and jbl selenium 15W600.

Mid-response of the 15WS600.

 

[tinitus]

I think that the 2" fatialpro offers very good low response usable down to 500Hz with a 24dB filter.

if you do that, wouldn't its own acostic-roll-off cause it to roll off earlier...and maybe even faster than 24db
which 'could' lead to phase ....

 

[Helmuth]

if you do that, wouldn't its own acostic-roll-off cause it to roll off earlier...and maybe even faster than 24db
which 'could' lead to phase ....

This is right, then you can filter the woofer steeper so you can match the phase with the horn driver works also fine with my own loudspeaker.
With the steep fillter the woofer can not mess up the clear tight midrange of the HF-driver. A win win situation isn't that great.

 

[Pano]

For measurements I have a calibrated berihnger mic with a phantom power soundcard. I have been playing with Holm Impulse software.

Then you are well on the road to enlightenment. Good for you.

Whatever drivers and horns you chose to use, measure, listen, tweak, measure, listen tweak, etc, etc. It can take a long time.
What works for me may not work for someone else, but we can give advice. For example: Bear likes the horns turned on their sides, I do not. I like a Bessel 4th order acoustic slope for my crossovers, some people don't. You'll have to find what works best for you.

You know that if you go SS amp and use the miniDSP on the 18", you could keep it open baffle. You might like that with the horns.

 

[Helmuth]

A other advantage of a 2" driver to a 1" is the shorter horn.
This is desirable to prevent any horn coloration of the response.

 

[Helmuth]

For highest sensitivety frontloaded midbas horn with the 18sound 15mb606, and bas-reflex port for bas extension.

here a nice horn design from volvotreter.

Sensitivety here is for 1pi situation. 108dB 1 W

103dB in 2pi radiation.